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The dopaminergic mind in human evolution and history

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Abstract

What does it mean to be human? There are many theories of the evolution of human behavior which seek to explain how our brains evolved to support our unique abilities and personalities. Most of these have focused on the role of brain size or specific genetic adaptations of the brain. In contrast, Fred Previc presents a provocative theory that high levels of dopamine, the most widely studied neurotransmitter, account for all major aspects of modern human behavior. He further emphasizes the role of epigenetic rather than genetic factors in the rise of dopamine. Previc contrasts the great achievements of the dopaminergic mind with the harmful effects of rising dopamine levels in modern societies and concludes with a critical examination of whether the dopaminergic mind that has evolved in humans is still adaptive to the health of humans and to the planet in general.

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... Shamanic ritual activities also elicit the release of endogenous opioids through: night-time rituals, when endogenous opioids are naturally highest; exposure to temperature extremes and self-infl icted wounds; situations of helplessness; and emotional manipulations that evoke fear (Prince, 1982). The roles of dopamine as a neurotransmitter and neuromodulator provide central aspects of the neurochemical explanation of the dynamics of shamanic alterations of consciousness (Previc, 2009 ). Dopamine is a neuromodulator involved in many diff erent brain systems, moderating not only unconditional reward and pleasure responses, but also reduction of pain and stress, formation of memory, social bonding, and most higher cognitive processes. ...
... Dopamine is implicated in a variety of visionary experiences (hallucinations, dreams, psychosis;Previc, 2006 ;Rolland et al., 2014 ). The reduction of serotonergic and noradrenergic modulation (control) results in the ascendance of the dopaminergic and acetylcholine systems that produce dreaming (Previc, 2009 ). The qualities that emerge with the disinhibition of dopaminergic networks in the ventral cortex and the limbic areas involve the central features of shamanic experiences and behaviours. ...
... A number of psychological disorders (i.e., bipolar disorder, obsessive compulsive disorder, and schizophrenia) associated with increased religiosity involve an overactivation of dopamine, particularly in the left hemisphere (Previc, 2006 ). Previc ( 2009 ) analyses the roles of the expanded dopaminergic system in human cognitive evolution. The dopamine system facilitates operations of goaldirected motivation and associations and making reward predictions, processes that are specifi cally adaptive in acquiring distant reward objects. ...
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Chapter 7 examines the cross-cultural manifestations of the various specific kinds of supernatural experiences as reflecting intrinsic features of human nature. The phenomenological dynamics of shamanic alterations of consciousness are linked to the physiological effects of ritual practices on the autonomic nervous system. These stimulate the modulatory neurotransmitter systems of serotonin, dopamine and the endocannabinoids, as well as the endogenous opioid system. These provide the biological bases for these experiences, involving the ability of diverse procedures and agents to provoke similar brain responses that enhance access to evolutionarily early strata of the brain. These brain areas provide the special cognitive qualities of consciousness that underlie perceptions of the supernatural. Ritual practices induce supernatural experiences through disrupting higher order information integration and top-down cognitive control, permitting emergence of cognitive processes related to ancient brain structures and primary process levels of cognition, identity and awareness. These biological bases for supernatural experiences are illustrated in an assessment of soul flight as involving a disassembling of the integration of innate capacities involved in the experience of body, self, and cognition. This and other shamanic alterations of consciousness are examined as adaptations that enhanced cognition through expanded access to unconscious mental processes.
... Most theories concerning when and how human intelligence and consciousness first arose focus on the role of expanded brain size or genetic mutations. However, Previc (2009) argued that characteristic human behavior evolved out of mostly epigenetic factors (influences such as direct placental transmission that can affect or override genetic expression) that led to an elevation of dopamine in the human brain. This is significant because dopamine, the most widely studied neurotransmitter in the brain, has been implicated in a number of processes that are fundamental to modern human behavior. ...
... This is significant because dopamine, the most widely studied neurotransmitter in the brain, has been implicated in a number of processes that are fundamental to modern human behavior. These include motivation, goal directedness, exploratory behavior, reward prediction, stimulus associations, and at least six cognitive abilities crucial to human intelligence: motor programming, working memory, cognitive shifting, abstract representation, temporal processing speed, and generativity/creativity (Previc, 1999(Previc, , 2009). Working memory is considered to be the most fundamental cognitive ability and the single best predictor of the general intellectual factor g (Kyllonen & Christal, 1990). ...
... Such strategic ability is associated with yet another dopaminergic trait-internal locus of control, the belief that the individual is in control of his or her own fate (DeClerk, Boone, & De Brabander, 2006). Strategic focus requires an inhibition of extraneous thoughts as well as a dampening of sympathetic emotional responses, consonant with dopamine's primarily parasympathetic action on the body in lowering blood pressure, reducing temperature, increasing peripheral vasodilation, and reducing oxygen consumption (Previc, 2009). The parasympathetic action of dopamine is a major clue in accounting for the parasympathetic dominance found in the majority, if not all, ASCDRs. ...
... Shamanic ritual and ASC evoke numerous healing mechanisms from counteracting anxiety to social support, with a range of salubrious psychophysiological effects (see Winkelman 2008, Chapters 9 & 10; 2010a Chapter 5), including: stimulation of endogenous opioid responses; producing a shift to parasympathetic dominance, evoking the relaxation response and counteracting stress hormones; inducing hypnotic susceptibility and eliciting placebo responses; enhancing access to the unconscious; and engaging diverse psychophysiological and psychosocial mechanisms that enhance psychoneuroimmunological responses. Previc (2009) proposes that the human drive to seek ASC directly engages the dopamine system, which is stimulated by diverse agents and ritual conditions (also see Winkelman 2010a, 2017a). Exogenous sources of neurotransmitters also produced ASC and contributed to the evolved psychology of shamanism (Winkelman 2021). ...
... Common to ASC is a disinhibition of dopaminergic extrapersonal brain systems, enhancing dopaminergic effects that stimulate cognitive processes key to the modern human psyche. Dopamine is involved in humans' unique cognitive abilities involving goal-directedness, learning stimulus associations and reward prediction, cognitive shifting, abstract representation, distal temporal processing, as well as generativity and creativity (Previc 2009). "[D]opaminergic activation results in the 'triumph' of extrapersonal brain activity over the body systems that anchor our self-concept and our body orientation as well as a triumph over the more 'rational' executive intelligence" (Previc 2009). ...
... Dopamine is involved in humans' unique cognitive abilities involving goal-directedness, learning stimulus associations and reward prediction, cognitive shifting, abstract representation, distal temporal processing, as well as generativity and creativity (Previc 2009). "[D]opaminergic activation results in the 'triumph' of extrapersonal brain activity over the body systems that anchor our self-concept and our body orientation as well as a triumph over the more 'rational' executive intelligence" (Previc 2009). The dopaminergic-induced abstract thought is exemplified in shamanic out-ofbody experiences and conceptualizations of spirit worlds, agent concepts that expand human capacity to explore our internal cognitive structures through symbols embodied in spirit concepts. ...
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This paper provides a method- and theory-focused assessment of religious behavior based on cross-cultural research that provides an empirically derived model as a basis for making inferences about ritual practices in the past through an ethnological analogy. A review of previous research provides an etic typology of religious practitioners and identifies their characteristics, selection-function features, the societal configurations of practitioners, and the social complexity features of the societies where they are found. New analyses reported here identify social predictors of the individual practitioner types in their relationships to subsistence and sociopolitical conditions (foraging, intensive agriculture, political integration, warfare, and community integration). These relations reveal the factors contributing to social evolution through roles of religious organization in the operation of cultural institutions. The discussion expands on the previous findings identifying fundamental forms of religious life in the relations of the selection processes for religious practitioner positions to their principal professional functions. These relationships reveal three biogenetic structures of religious life involving (1) alterations of consciousness used in healing rituals, manifested in a cultural universal of shamanistic healers; (2) kin inheritance of leadership roles providing a hierarchical political organization of agricultural societies, manifested in priests who carry out collective rituals for agricultural abundance and propitiation of common deities; and (3) attribution of evil activities, manifested in witches who are persecuted and killed in subordinated groups of societies with political hierarchies and warfare. These systematic cross-cultural patterns of types of ritualists and their activities provide a basis for inferring biogenetic bases of religion and models for interpreting the activities, organization, and beliefs regarding religious activities of past societies. Cases are analyzed to illustrate the utility of the models presented.
... A similar pattern has been observed across a wide range of countries . This rather striking pattern is regarded as a marker of rising dopaminergic activation during adolescence (Chambers et al., 2003;Wahlstrom et al., 2010) and may reflect activity in the midbrain dopamine pathway ascending from the ventral tegmental region (Ikemoto, 2007;Previc, 2009). This pathway traverses through the ventral striatum before branching into the orbital and ventromedial frontal cortex. ...
... One of the indicators of the BAS known as fun seeking is highly related to sensation seeking, while two other related indicators (reward responsiveness and drive) may be more associated with achievement motivations (Romer et al., 2016). What is often neglected in discussion of imbalance is a rise in dopamine activity in dorsal and medial PFC (Meng et al., 1999;Weickert et al., 2007) fed by another pathway originating primarily in the substantia nigra that ascends through dorsal striatum into dorsal PFC and parietal cortex, regions that control movement and higher order decision making (Ikemoto, 2007;Previc, 2009). Dopamine neurons in this pathway appear to serve more global salience and cognitive processing functions than the ventral route (Bromberg-Martin et al., 2010;Roeper, 2013). ...
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Recent neuroscience models of adolescent brain development attribute the morbidity and mortality of this period to structural and functional imbalances between more fully developed limbic regions that subserve reward and emotion as opposed to those that enable cognitive control. We challenge this interpretation of adolescent development by distinguishing risk-taking that peaks during adolescence (sensation seeking and impulsive action) from risk taking that declines monotonically from childhood to adulthood (impulsive choice and other decisions under known risk). Sensation seeking is primarily motivated by exploration of the environment under ambiguous risk contexts, while impulsive action, which is likely to be maladaptive, is more characteristic of a subset of youth with weak control over limbic motivation. Risk taking that declines monotonically from childhood to adulthood occurs primarily under conditions of known risks and reflects increases in executive function as well as aversion to risk based on increases in gist-based reasoning. We propose an alternative Life-span Wisdom Model that highlights the importance of experience gained through exploration during adolescence. We propose, therefore, that brain models that recognize the adaptive roles that cognition and experience play during adolescence provide a more complete and helpful picture of this period of development.
... Fred Previc (2009) proposes that these shamanic experiences are a function of the activation of the dopamine system. Dopamine plays fundamental roles in mammals, mediating mother-infant bonding, mating and affiliation in social groups, having central roles in managing emotions and social relations. ...
... Chapter 21: Shamanism and the Brain Behaviorally induced and drug-induced alterations of consciousness affect functioning of both the serotonergic and dopaminergic neurotransmitter systems, neuromodulators that have complementary roles in balancing numerous brain functions and its other neurotransmitter systems. Fred Previc (2009) characterizes the inhibition of dopamine release by serotonin as one of the brain's most important neurochemical interactions, with the serotonergic and noradrenergic systems of the right hemisphere inhibiting the dopamine system and the left hemisphere. Shamanic activities alter consciousness by stimulating both serotonergic and dopaminergic neurotransmitter systems, as well as the endocannabinoid neurotransmitter system, which together produce a variety of aspects of shamanistic experiences. ...
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... The inhibition of dopamine release by serotonin is central to neurochemical balance in the brain, with the serotonergic and noradrenergic systems of the right hemisphere inhibiting the dopamine system and the left hemisphere (Previc, 2009). This blockage of serotonin's inhibitory functions results in the disinhibition of the dopaminergic system, releasing a flood of information that is normally inhibited by serotonin. ...
... In addition to direct stimulation of the visual system by psychedelics, there is the psychedelic effect of reduction of serotonergic and noradrenergic inhibitory effects on the mesolimbic temporal lobe structures. This inhibition permits the ascendance of the dopaminergic and acetylcholine systems, with the loss of serotonin's inhibitory effects and ascendance of the dopaminergic system resulting in a variety of visual syndromes, especially hallucinations and dreaming (Hobson, 2001;Previc, 2009). These typical visual and hallucinatory experiences produced by psychedelics are also a consequence of the enhanced connectivity between the visual cortex and memory centers, an increase of information input to the visual systems from internal information. ...
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Anthropology, Shamanism and Hallucinogens Introduction Psychedelics and Humans’ Evolved Ecopsychology A Shamanic Ecopsychology Shamanism: The Institutionalization of Hallucinogen Use Shamanism as a Cross-cultural Complex Cross-cultural Features of Shamanism Entheogens in Shamanism Entheogenic Nature: Animism and the Origins of Shamanic Ecopsychology Animism and Self-Development Shamanic Uses of Entheogens Therapeutic Uses of Hallucinogens Shamanic Ritual Procedures for Managing Consciousness Food Restrictions Sexual Abstinence Drumming, Singing and Chanting Over-Night Rituals and “Dreamtime” Types of Shamanic ASC Shamanic Flight and Visionary Experiences The Shaman’s Initiatory Crisis: Death and Rebirth Animal Transformation A Psychedelic Neurophenomenology Serotonergic regulation and psychedelic deregulation Psychointegration and the Integrative Mode of Consciousness Psychointegration as Liberation of the “Animal Brains” Primary Process Thinking Novel meaning and symbolic interpretation Presentational symbolism: a visual epistemology Conclusions
... Consumption of omega-3 and omega-6 fatty acids in correct proportion is necessary for intellectual, cognitive and social skills development in homo-sapiens [52]. Findings of two large studies (Sydney Diet Heart Study (1966)(1967)(1968)(1969)(1970)(1971)(1972)(1973) and Minnesota Coronary Experiment (1968)(1969)(1970)(1971)(1972)(1973) indicated that replacement of naturally evolved dietary saturated fats with oils rich in linoleic acid (omega-6 fatty acid) increased the chance of mortality from [44]. ...
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Consumption of fats and oils in the ancient world was examined as a window to human nutritional needs and compared with lipid usage in the modern world, post-1900. In earlier periods, the natural and only source of edible fats and oils came from both animals and plants. These fats and oils played a vital role in the evolution of the human body structure, supporting many biochemical functions. Artifacts from prehistoric periods and the ancient world had indicated that humans were evolutionarily adapted to consume saturated lipids. They also consumed unsaturated fats and oils extracted from animals and plants, now identified as omega-3 to omega-6 in the fatty acid ratio of 1:1, commonly derived from naturally consumed unprocessed products and food sources. These fats and oils assisted in providing the ingredients for the building up of cells and maintaining their structural integrity in tissues, including the brain and other important internal organs, as well as providing energy for many biochemical processes in the body. The double bonds distributed throughout fatty acid carbon chains are a characteristic of unsaturated vegetable oils. They are more structurally diverse in polyunsaturated fats and oils with the greater preponderance for carbon-to-carbon double bonds distributed in the carbon chains. These double bonds are susceptible to generating free radicals. This article considers potential problems that proponents of the prevailing diet-heart cholesterol paradigm of the past 60 years may have neglected. It also presents the possible consequences of abandoning the evolutionarily inherited foods containing extracted natural saturated and monounsaturated fats and oils. Furthermore, the article addresses the contribution of docosahexaenoic and eicosapentaenoic acids to immunity and the possible connection of excess consumption of omega-6 fatty acid to the marked rise in obesity and other non-communicable diseases in modern civilization.
... From this perspective, it can be advanced that meat was increasingly incorporated into ancestral diets due to ecological pressure and behavioural and physiological adaptations, whereby a clear shift from mostly herbivore to high-quality omnivore diets was triggered (Aiello and Wheeler 1995;Flinn et al. 2005). Eventually, this caused an adaptation towards a shorter digestive tract and led to the liberation and provision of additional energy and building blocks for the development of larger brains and, in parallel, enhanced conceptual skills (Previc 2009;Pfefferle et al. 2011). The selective pressure steering this cognitive development fuelled by meat-eating was probably closely related to the diverse intellectual challenges associated with complex foraging behaviour, the use of tools, intense cooperation, and food sharing (Stanford and Bunn 2001;Tomasello et al. 2012). ...
Chapter
Despite its longstanding biosocial evolutionary background, the consumption of meat has nowadays become a controversial activity for a variety of reasons, being mostly related to anxieties about health, environmental impact, and animal welfare. The present chapter will outline the biosocial functions of meat within human communities, including the particularities of the contemporary state-of-affairs in postdomestic societies. Moreover, an overview will be given of the (historic) discourses on the role of meat in health and disease. The heterogeneity within human-meat interaction schemes, both with respect to meat production and utilization, suggests a tremendous amount of research potential related to the position of unconventional meat types in diets and culture. From a minoritarian position they may be useful in challenging given ideas and established concepts about meat, which are usually construed based on the dominant position of beef, pork, and chicken within Western countries. Unconventional meats may thus help us to reflect differently on human-meat interactions and to deal with future challenges that require innovative thinking.
... Aunque en un principio, se trataba de una creencia popular anecdótica, bastante antigua, numerosos estudios clínicos recientes, han verificado repetidamente la afirmación de Sócrates, demostrando la asociación empírica entre la enfermedad mental y la creatividad/artística inusual (p. Ej., Akinola & Mendes, 2008;Akiskal & Akiskal, 1988Andreasen, 1987Andreasen, , 2008Andreasen & Canter, 1974;Baas, De Dreu, & Nijstad, 2008;Davis, 2009;Goodwin & Jamison, 2007;Jamison, 1989Jamison, , 1993Jamison, , 2011Kyaga, Lichtenstein, Boman, Hultman, & Långström, 2011;Ludwig, 1992Ludwig, , 1994Murray & Johnson, 2010;Previc, 2009;Richards, Kinney, Lunde, & Benet, 1998;Santosa et al., 2007;Simeonova, Chang, Strong, & Ketter, 2005;Tremblay, Grosskopf, & Yang, 2010;Weissman-Arcache & Tordjman, 2012). ...
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Los seres humanos pueden caracterizarse por muchos rasgos: el lenguaje, la socialidad compleja y los avances tecnológicos son sólo algunos de ellos. En cada uno de ellos subyace un sofisticado sistema cognitivo. Los arqueólogos reconocen la importancia de la cognición en la evolución del Homo Sapiens sapiens al distinguir entre los humanos anatómicamente modernos (HAM), que son restos óseos equivalentes a los nuestros y que aparecieron por primera vez en África unos 175.000 (o más) años antes del presente (AP), y los humanos cognitivamente modernos (HCM), que posiblemente no aparecieron por primera vez hasta el inicio del Paleolítico Superior, unos 50.000 AP. 1 Los HCM han sido reconocidos como tales, debido a la aparición de complejos conjuntos de herramientas y prácticas adaptativas, junto con un arte sofisticado. Aunque existe un debate, sobre la rapidez con la que la evolución cognitiva siguió a los cambios esqueléticos, hay consenso en que ambos no evolucionaron simultáneamente. La cognición es, en sí misma, un fenómeno complejo que implica algo más que la lógica y las habilidades computacionales y analíticas. En el razonamiento, también están implicadas las emociones, ya que éstas evolucionaron junto con el razonamiento y desempeñan un papel activo en los procesos cognitivos.
... With the advent of storytelling also came the possibility of it getting out of control. If dopamine is more active than normal in the brain, the balance of neural rewiring can be upset (Previc 2009). Discrepancies can be given undue weight, and beliefs may become detached from reality (Fletcher and Frith 2009). ...
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Human language and intelligence go far beyond biological needs, allowing us to discuss abstract ideas, construct imaginary worlds, and do science and mathematics. How did such an ability arise? I propose that a major contributing factor was an arms race between truth and deception in storytelling. In honeybees, an elaborate language could evolve because reproductive conflicts of interest between individuals were reduced. For humans, however, reproductive conflicts of interest became a spur for increasing intelligence. Through the drive to negotiate social interactions, primate intelligence reached the point where knowledge could be shared through basic problem–resolution proto-stories, building on the way animals learn. As soon as honest proto-stories became possible, so did dishonest ones, ushering in an arms race between truth and deception, through which stories, language and skills in detecting lies through contradictions, were driven to ever greater heights. In telling stories to others, humans also told them to themselves, allowing them to think consciously and plan ahead. Through fictions they could share understanding by making discrepancies stronger and more engaging. Science arose when skills in detecting lies through empirical contradictions were applied to stories about how the world operates, whereas mathematics arose when skills in discerning lies through self-contradiction were applied to abstract reasoning. Both scientists and mathematicians used the storytelling structure of problem–chain–resolution to share their findings, founded on the principles of animal learning. Human intelligence thus arose through, and continues to depend upon, a balance between trust and doubt in the stories we share.
... Notwithstanding its limitations, the present study adds important information to the knowledge of the neurogenetic underpinnings of MA: (a) a thorough understanding of the origins of MA requires considerations of both environmental and genetic factors; (b) the dopaminergic system, a multifunctional system especially important in human evolution (Previc, 2009;Piffer, 2013), is also relevant for clarifying the neurobiological underpinnings of MA; (c) testing for associations between psychological phenotypes and single-loci genetic markers should consider all possible genetic models (dominance, codominance, and heterosis); and (d) sex differences in MA associated with the COMT Val158Met polymorphism are detectable even before puberty. Sex differences in the effect of Val158Met polymorphism in prepubertal children have already been described for cognitive functions (Barnett et al., 2007). ...
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Math anxiety (MA) is a phobic reaction to math activities, potentially impairing math achievement. Higher frequency of MA in females is explainable by the interaction between genetic and environmental factors. The molecular-genetic basis of MA has not been investigated. The COMT Val158Met polymorphism, which affects dopamine levels in the prefrontal cortex, has been associated with anxiety manifestations. The valine allele is associated with lower, and the methionine allele with higher, dopamine availability. In the present study, the effects of sex and COMT Val158Met genotypes on MA were investigated: 389 school children aged 7–12 years were assessed for intelligence, numerical estimation, arithmetic achievement and MA and genotyped for COMT Val158Met polymorphism. The Math Anxiety Questionnaire (MAQ) was used to assess the cognitive and affective components of MA. All genotype groups of boys and girls were comparable regarding genotype frequency, age, school grade, numerical estimation, and arithmetic abilities. We compared the results of all possible genetic models: codominance (Val/Val vs. Val/Met vs. Met/Met), heterosis (Val/Met vs. Val/Val plus Met/Met), valine dominance (Val/Val plus Val/Met vs. Met/Met), and methionine dominance (Met/Met plus Val/Met vs. Val/Val). Models were compared using AIC and AIC weights. No significant differences between girls and boys and no effects of the COMT Val158Met polymorphism on numerical estimation and arithmetic achievement were observed. Sex by genotype effects were significant for intelligence and MA. Intelligence scores were higher in Met/Met girls than in girls with at least one valine allele (valine dominance model). The best fitting model for MA was heterosis. In Anxiety Toward Mathematics, heterozygous individuals presented MA levels close to the grand average regardless of sex. Homozygous boys were significantly less and homozygous girls significantly more math anxious. Heterosis has been seldom explored, but in recent years has emerged as the best genetic model for some phenotypes associated with the COMT Val158Met polymorphism. This is the first study to investigate the genetic-molecular basis of MA.
... Brain development involves a chain of interactions with the external world, that begins with sensory processing of the outside information that enter the body through primary senses: vision, hearing and touch, and movement; which further evolve as we grow (or decline as we age) by learning skills that support this process [106]. The genetic and neurochemical signaling pathways that support this learning process are tied to reward and fear processing, and the brain learns the world through an iterative evaluation of the situation and stimuli that are rewarding and enhance its well-being, and avoiding or fighting those that threaten it [107][108][109][110]. These mechanisms create a closed-loop control system, any of which if broken will put the body in the state of allostatic load (or stress) [111,112]. ...
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User retention is the first challenge in introducing any information and communication technologies (ICT) for health applications, particularly for seniors who are increasingly targeted as beneficiaries of such technologies. Interaction with digital technologies may be too stressful to older adults to guarantee their adoption in their routine selfcare. The second challenge, which also relates to adoption, is to supply empirical evidence that support the expectations of their beneficial outcomes. To address the first challenge, persuasive technologies such as serious games (SGs) are increasingly promoted as ludic approaches to deliver assistive care to older adults. However, there are no standards yet to assess the efficacy of different genres of games across populations, or compare and contrast variations in health outcomes arising from user interface design and user experience. For the past 3 decades, research has focused either on qualitative assessment of the appeal of digital games for seniors (by game designers) or on the quantitative evaluation of their clinical efficacy (by clinical researchers). The consensus is that interindividual differences play a key role in whether games can be useful or not for different individuals. Our challenge is to design SGs that retain their users long enough to sustain beneficial transfer effects. We propose to add a neuropsychological experimental framework (based on the appraisal theory of stress and coping) to a Gerontoludic design framework (that emphasizes designing positive and meaningful gaming experience over benefit-centric ones) in order to capture data to guide SG game development. Affective Game Planning for Health Applications (AGPHA) adds a model-driven mixed-methods experimental stage to a user-centered mechanics-dynamics-aesthetics game-design cycle. This intersectoral framework is inspired by latest trends in the fields of neuroimaging and neuroinformatics that grapple with similar challenges related to the psychobiological context of an individual's behaviors. AGPHA aims to bring users, designers, clinicians, and researchers together to generate a common data repository that consists of 4 components to define, design, evaluate, and document SGs. By unifying efforts under a standard approach, we will accelerate innovations in persuasive and efficacious ICTs for the aging population.
... During this process, a gradual transition to an omnivore diet took place with repercussions on the anatomy and functional aspects of the human digestive system and brain (Aiello & Wheeler, 1995). Cerebral expansion during evolution has thus been fueled by meat, through the liberation of energy and the provision of building blocks and cofactors (Pfefferle et al., 2011;Previc, 2009;Williams & Hill, 2017). It is noteworthy that early humans have been described with a very Deleuzian concept by paleoanthropologist Domínguez-Rodrigo (quoted in Gupta, 2016) as "meat-eating machines," in contrast to the "plant-processing machines" embodied by other primates. ...
Chapter
In contemporary dietary advice, meat is depicted as a pharmakon: it is believed to either heal or poison the human body (and mind). Often, it also serves as a scapegoat for a wide range of public health issues and other societal problems. Related attitudes, practices, and beliefs pertain to a demarcated mode of thinking or episteme that is characteristic for the so-called post-domestic or industrialized societies. The latter are not only typified by an abundant yet largely concealed production of meat, but increasingly also by moral crisis and confusion about its nutritional meaning. For an improved appreciation of the ambiguous position of meat in human health and disease, as well as the concomitant scattering into different subject positions (e.g., the omnivore, flexitarian, vegetarian, vegan, permaculturalist, and carnivore position), an interdisciplinary approach is required. To this end, the current study tentatively combines food research with a selection of (post-structuralist) concepts from the humanities. The aim is to outline a historical and biosocial need for meat (as well as its rejection) and to analyze how its transformative effects have contributed to a polarized discourse on diet and well-being in academia and society at large. Excessive categorization (for instance with respect to meat's alleged naturalness, normalness, necessity, and niceness) and Manichean thinking in binary opposites are among the key factors that lead to impassioned yet often sterile debates between the advocates and adversaries of meat eating in a post-truth context.
... Dostoevsky presented most of these features (Hughes, 2005: 537;Baumann et al., 2005;Rayport et al., 2011). The temporal lobe personality bears a likeness to the Dopaminergic mind (Previc, 2006(Previc, , 2009, the Geschwind syndrome (Benson, 1991) Waxman & Geschwind, 1975 "Interictal personality disorder": (1) Deepened emotions, (2) circumstantial thought, (3) concern with philosophical or religious beliefs, and (4) a change in sexual behavior Bear & Fedio, 1977 (1) Emotionality, (2) mania, (3) depression, (4) guilt, (5) humorlessness, (6) altered sexual interest, (7) aggression, (8) anger and hostility, ...
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Fyodor Mikhailovich Dostoevsky is one of the best Russian novelists. It is also known that he had been suffering from epilepsy―one can find many descriptions of this particular condition in Dostoevsky’s novels. These writings are most probably based on his personal experience. There are numerous neurological hypotheses about the type of epilepsy with which Dostoevsky suffered, the most notorious feature of his type of epilepsy being the so-called “ecstatic aura.” In fact, the type of epilepsy Dostoevsky experienced is often termed “Dostoevsky’s epilepsy with ecstatic aura.” In thecurrent article, I offer a review of the literature on Dostoevsky’s epilepsy. Subsequently, the notorious feature “ecstatic aura” is compared with mystical experience, and a conclusion is reached: the two states are in fact identical in the sense that mystical experience can occur during ecstatic aura. A neuroscientific explanation of the experience is presented as well. Finally, a philosophical analysis is performed.
... With the saturation of the serotonin system, its inhibition functions are released, allowing for the manifestations of the dopamine system. Previc (2009) has characterized shamanistic experiences as reflecting functions of the dopaminergic mind, exemplified in our ability to engage in extrapersonal cognition. Dopamine functions to process information regarding events distal in space and time from the physical body and activities of spatial and temporal abstraction involved in understanding causal relationships, and in the pursuit of goal-directed responses. ...
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Shamanism and possession are central concepts in the religious practices of many “premodern” societies, with substantial similarities manifested across cultures and time that reflect their basis in human nature. Shamans and possession both involve ritual alteration of consciousness but differences between them are illustrated by cross‐cultural studies and the distinctive experiential features associated with their respective activities. Shamans' characteristic alterations of consciousness involve soul flight, what modern psychology recognizes as out‐of‐body experiences that involve a separation of one's visual perspectives from self and body. Possession episodes differ in the experience of control by spirits and amnesia of the event, reflecting psychosocial features that produce dissociation. Shamanism and possession nonetheless share biological features in their elicitation of ancient brain systems to modify the consciousness in relation to healing and spiritual experiences.
... Changes to neuro-hormonal regulation continued to H. erectus, whose morphology and social/technological behaviour was modern. Additionally, by the time of H. erectus there would have been significant changes to dopaminergic systems due to complex social environments and sophisticated hunting behaviours which increased meat/seafood intake (Previc, 2009). Considerable increase in physical activity level (PAL) of H. erectus onwards (Panter-Brick, 2002), necessitated more efficient dopaminergic metabolic pathways in order to optimise thermo-regulation, which may have been exapted for improving cognitive abilities in the pre-frontal cortex (Hoffmann, 2013). ...
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This article will argue that future outer space flight may cause micro-evolutionary changes to the human body, and will explain the nature of these changes from the point of view of evolutionary medicine. Initial adaptation will be protracted with considerable problems to long term outer space flight, especially inter-generational outer space travellers. The authors examine possible neuro-behavioural and psycho-social possibilities for long term outer space travellers due to separation from the biotic environment in which humans have evolved. The authors also develop novel ideas in reducing possible deleterious micro-evolutionary effects during long term outer space flight.
... Dopamine has been examined, perhaps most notably in the context of Parkinson's Disease (de la Fuente-Fernández et al., 2001), but also in the context of motivation (Scott et al., 2008). Representations of future events are an important component of placebo effects, and dopamine is implicated in many future-focussed mental processes (Previc, 2009), including expectation (Enck, Benedetti, & Schedlowski, 2008). ...
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Placebo and nocebo effects are a factor in sports performance. However, the majority of published studies in sport science are descriptive and speculative regarding mechanisms. It is therefore not unreasonable for the sceptic to argue that placebo and nocebo effects in sport are illusory, and might be better explained by variations in phenomena such as motivation. It is likely that, in sport at least, placebo and nocebo effects will remain in this empirical grey area until researchers provide stronger mechanistic evidence. Recent research in neuroscience has identified a number of consistent, discrete and interacting neurobiological and physiological pathways associated with placebo and nocebo effects, with many studies reporting data of potential interest to sport scientists, for example relating to pain, fatigue and motor control. Findings suggest that placebos and nocebos result in activity of the opioid, endocannabinoid and dopamine neurotransmitter systems, brain regions including the motor cortex and striatum, and measureable effects on the autonomic nervous system. Many studies have demonstrated that placebo and nocebo effects associated with a treatment, for example an inert treatment presented as an analgesic or stimulant, exhibit mechanisms similar or identical to the verum or true treatment. Such findings suggest the possibility of a wide range of distinct placebo and nocebo mechanisms that might influence sports performance. In the present paper we present some of the findings from neuroscience. Focussing on fatigue as an outcome and caffeine as vehicle, we propose three approaches that researchers in sport might incorporate in their studies in order to better elucidate mechanisms of placebo/nocebo effects on performance.
... 631-638;Wong & van Tol, 2003, pp. 280-281;Previc, 2009, pp. 91-95): attentional (sustained and selective attention), memory (working, long-term and semantic types of memory), executive deficits 65 (volition, planning and self-regulation), deficits in the sensitivity of both perception and awareness of one's own body, deficits in visual depth perception and global intellectual decline, but also impairments and insensitivity in the processing of contextual information and in ‗social cognition' ( Wong & van Tol, 2003, p. 280) which consists of perception of emotions of other people, theory of mind (ToM), empathizing, self-reference and other. ...
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The thesis represents a detailed philosophical account performed as a multidisciplinary study of some of the main functions of the mind. The Freudian framework of primary and secondary thought processes embedded into his psychoanalysis and metapsychology is used as a foundation of the analysis of acute schizophrenic psychosis, psychedelic state and mystical experience. Primary process thought is primitive, irrational, illogical, preverbal, pleasure oriented. Secondary process thought is advanced, rational, logical, verbal, reality oriented. Due to the multitude of critiques against Freud an attempt is performed to grant an objective status to Freudian psychoanalysis and metapsychology via the methodology of neuropsychoanalysis. Various psychiatric, psychoanalytical, psychological and neuroscientific mechanisms are studied and applied in the analysis. Analyzed major points include: delusions, formal thought disorder, and self, cognitive, affective, perceptual and volitional disturbances. All deviations are in fact primary process manifestations, that is, disinhibitions of the id. They are due to secondary process impairments or weakening of the defense mechanisms of the ego. In the thesis, multiple parallels in terms of mechanisms of acute schizophrenic psychosis, psychedelic state and mystical experience were established. There is substantial overlapping of functional mechanisms (repression, functionality of psychic complexes and affectivity, functioning of cognition, salience attribution, thalamic filtering and gating, and psychopharmacology) leading to primary thought process manifestations when impaired and primary thought process mechanisms proper (displacement, condensation, symbolization) in all of the three states, with subtle differences observed in mystical experience. Finally, the application of those methods provides a scientific explanation of the mechanisms of mystical experience as an alternative to the classical theistic interpretations.
... Interest as continuous phenomenon is dependent on dopamine D 2 receptors in the mesolimbic system. Their activation leads to the unselective arousal that apparently is represented by curiosity ( Winterer & Weinberger, 2004: 687;Previc, 2009: 64). Indeed, dopamine, on the level of dorsal and ventral striatum, especially its D 1 and D 2 type of postsynaptic receptors, is related to psychomotor functioning and motivation. ...
Preprint
Creativity is one of the areas which continuously attracts attention. In an interdisciplinary spirit, this article focuses on the dynamics of creativity with respect to Freudian psychoanalytical thought processes and Jaspers' conception of a boundary situation. This effort is correlated with the newest research findings in cognitive neuroscience and neurocognitive psychology of creativity. Philosophical research is also brought in to explain the activity of creative thought and a new conception of creativity is offered, with a third thought process used along with a miniature boundary situation. This represents a development and extension of the original ideas of Sigmund Freud and Karl Jaspers. The current article constitutes thus a review of the intersection of creativity research, the metapsychology of Sigmund Freud and the existential philosophy of Karl Jaspers. This makes it a neurophilosophical discussion par excellence and represents both a theoretical project and translation. Creativity as unique human experience is illuminated in the miniature of boundary situation as controlled disinhibition of the intellect or regression in the name of the ego and as controlled spiral movement via dialectical "jumps" or "leaps".
... It has been suggested that the quality of human brain functions depends more on neurohormonal and neurotransmitter regulation than on its size [63]. Behavioural differences between mammals may also result more from neurohormonal regulation than brain size [60]. ...
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There exists a negative allometry between vertebrate brain size and body size. It has been well studied among placental mammals but less is known regarding marsupials. Consequently, this study explores brain/body ontogenetic growth in marsupials and compares it with placental mammals. Pouch young samples of 43 koalas (Phascolarctos cinereus), 28 possums (Trichosurus vulpecula), and 36 tammar wallabies (Macropus eugenii) preserved in a solution of 10% buffered formalin, as well as fresh juveniles and adults of 43 koalas and 40 possums, were studied. Their brain size/body size allometry was compared to that among humans, rhesus monkeys, dogs, cats, rats, guinea pigs, rabbits, wild pigs, and mice. Two patterns of allometric curves were found: a logarithmic one (marsupials, rabbits, wild pigs, and guinea pigs) and a logistic one (the rest of mammals)
... The primary neurotransmitter that regulates processing of objects in the extrapersonal space is dopamine [13][14][15][16]. Dopamine is most widely known for its role in goal directed activity. ...
... The theory says that the "dopaminergic society" is characterized by high intelligence, personal destiny sense, religious/cosmic concerns and obsession with achieving goals. 11 Regarding appetite, DA has varying effects depending on the brain area and the type of receptor stimulated. It has anorectic effect when it operates in the ARC, LHA and NAc, but acts as orexigenic in the ventromedial hypothalamic nucleus (VMH). 2 Several studies have related the dopaminergic brain circuits in eating behavior. ...
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Regulation of food intake, energy expenditure and store are strikingly linked to obesity. Homeostatic control of food intake, hunger and satiety involves adipose and gastrointestinal hormones, such as leptin, insulin and ghrelin, which eventually affect neuronal signaling in the hypothalamus arcuate nucleus. On the other hand, hedonic control of food intake relates to substances such as opioids, endocannabinoids, gamma-aminobutyric acid, serotonin and dopamine, which act on the motivation and reward mechanisms. Dopamine is a precursor of noradrenaline and adrenaline and modulates a number of physiological functions, such as appetite, depending on the brain area and the type of receptor stimulated. It has been established as the main neurotransmitter of the hypothalamic reward system. Beyond the homeostatic and hedonic energy balance control, genetic aspects are also tightly involved in obesity pathophysiology. In this context, some Single Nucleotide Polymorphism (SNP) has been linked to common obesity. Here, we highlight the role of the dopamine receptor D2 gene TaqAI polymorphism, which affects the D2 receptor availability and has been associated to obesity. Therefore, the aim of this mini review is to cover basic aspects of food intake, energy balance, dopamine-related aspects, including genetic ones, and the relation with obesity.
... As such, they are noxious and impair the overall cognitive performance of the individual as well as their affective sensitivity. Both of them have negative consequences, although overvalued ideas could sometimes have a positive outcome (Previc, 2009); it always depends on the given case and context. The possible continuum formed by these ideas is of big interest, specifically at the point where the overvalued ideas are transformed into delusions or the other way round-namely when delusions lose their affective power, start to dissolve and are transformed into delusion-like ideas. ...
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Abstract: Delusions, even nowadays, still puzzle psychiatrists. Overvalued ideas were always regarded as a result of the functioning of a disordered mind. Delusion and overvalued ideas are psychiatric concepts. Nonetheless, they are nowadays analyzed also from a philosophical point of view. In the current article, I argue from a philosophical perspective that delusion and overvalued ideas actually lay on a single continuum in the sense that overvalued ideas can escalate to delusions and delusions can degrade to overvalued ideas. After a thorough review of both disorders, I offer an account for a positive role of overvalued ideas when they are being guided. Keywords: delusions, overvalued ideas, continuum, comparative analysis, philosophy of mind, dopaminergic mind, neurobiology
... A highly dopaminergic society is fast-paced and even manic, given that dopamine is known to increase activity levels, speed up our internal clocks and create a preference for novel over unchanging environments. 47 Previc reels off a list of 'hyperdopaminergic disorders', including depression, obsession-compulsion, autism, schizophrenia, Tourette's, Alzheimer's and Parkinson's. We can also add ADHD to this list, though it is also, ironically, linked to traits that can thrive in hyperdopaminergic conditions. ...
... In support of the notion that behavioural and cognitive modernity existed in H. erectus, it is worth noting research that suggests the up regulation of the dopaminergic system may have occurred in this species (DeLouize et al. 2017). Dopamine is believed to be involved in cognitive skills such as human language, motor planning, working memory, cognitive flexibility and abstract reasoning -abilities that are believed to have facilitated endurance running, hunting and the demographic expansion of early hominins (Previc 1999;Previc 2009). Given the ability of H. erectus to make Acheulean tools and the possibility of maritime craft manufacture and navigation, the role of dopamine in novelty-seeking, exploratory behaviour and tool manufacture, suggests the dopaminergic system may have been central to the evolution of H. erectus (DeLouize et al. 2017). ...
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In this article we provide evidence that evolutionary pressures altered the cranial base and the mastoid region of the temporal bone more than the calvaria in the transition from H. erectus to H. sapiens. This process seems to have resulted in the evolution of more globular skull shape – but not as a result of expansion of the brain in the parietal regions but of reduction of the cranial base and the mastoid region relative to the parietals. Consequently, we argue that expansion of the parietals seems to be unrelated to brain evolution, but is more a by-product of reduction in other regions of the skull, reduction that may be related to dietary factors. Additionally, these findings suggest that cognitive and behavioural modernity may not necessarily be dependent on brain shape. Also, it cannot be attributed to the change in brain size because H. erectus and modern human cranial capacities overlap substantially. Consequently, we suggest H. erectus possessed the full suite of cognitive adaptations characteristic of modern humans without possessing a globular skull with flared parietals. Our results also support the theory that paedomorphic morphogenesis of the skull was important in the transition from H. erectus to H. sapiens and that such changes may be related to both dietary factors and social evolution.
... Using the theory of information, one can quantify the urban landscape in such a way as can easily be seen by the public on Akademika Sakharova Avenue in Moscow (Previc, 2009). When walking along it-after the first step, or the 10th, or the 100th-one will not see any changes. ...
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This article considers the concept of a city as an organized and complex system, the main inhabitant/consumer of which is a human being. The human being, in its turn, is also a complex organized system. Separately, the functioning of both these systems is well enough studied, however to date in science little attention has been paid to the interaction of these systems with each other. The main object of study in the article is the psychological state of a person in an urban environment. The concepts of interest, excitement, boredom, stress, and so forth are investigated and their impact on physical health. Moreover, the problem of interaction of the real world with virtual technologies—their confrontation and mutual help in an urban context is also considered. At the end, there are several assumptions about the return of full‐bloodedness to the streets of modern cities. It was concluded that the cities can help stimulate the brain cells of citizens and maintain their brain activity at a certain level of productivity.
... Areas such as the striatum, amygdala, and mesolimbic pathway, are instrumental in processing and controlling hormones that create reward, drive, emotion, stress, and other facts that pour into motivation. Primary among those is dopamine, which signals an intent to explore further (Previc 2011). It is associated with excitement, whether positive or negative. ...
Chapter
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The application of artificial intelligence (AI) algorithms is improving everyday tasks worldwide. But while the internet has transformational benefits, it also has its severe drawbacks. Internet infrastructure is extremely expensive and requires large private investment. To profit while giving free access has necessitated the presentation of personalized advertisements. Psychology-based strategies are employed to keep users perpetually engaged, often using emotional or aggressive stimuli that attract attention. Users’ responses and personal data are harvested from multiple sources and analysed through complex statistical algorithms. When hundreds of variables are collected on a person, personality traits, expense patterns, or political beliefs become fairly predictable. This happens because human cognition and emotions evolved for survival in Palaeolithic environments, and certain features are universal. Technology companies sell behaviour prediction models to anyone willing to pay. According to client purposes, users can be prodded to spend money or adopt politically motivated beliefs. Furthermore, smartphone beacons and face recognition technology make it possible to track political activists as well as criminals. Through the use of AI, therefore, tech corporations “design minds” to act as directed and socially engineer societies. Large ethical issues arise, that include privacy concerns, prediction errors, and the empowerment of transnational corporations to profit from directed human activities. As AI becomes part of everyday lives, the internet that intended to bring universal knowledge to the world is unwittingly throwing us back into the Palaeolithic era. Now more than ever, humans ought to become more peaceful and content rather than be driven by ever-increasing emotion-driven contests. This chapter discusses these important issues with the direct or indirect actions that need to be taken to maintain sustainable consumption, world peace, and democratic regimes.
... TH converts tyrosine to L-DOPA, the precursor of dopamine in the CNS (Claustre, Balende, & Pujol, 1996). Increased dopaminergic activity is key for higher cognitive skills such as working memory, abstract reasoning and language (Previc, 2002(Previc, , 2009Saniotis et al., 2020). ...
Chapter
Thyroid hormone (TH) signaling, a highly conserved pathway across vertebrates, is crucial for brain development and function throughout life. In the adult mammalian brain, including that of humans, multipotent neural stem cells (NSCs) proliferate and generate neuronal and glial progenitors. The role of TH has been intensively investigated in the two main neurogenic niches of the adult mouse brain, the subventricular and the subgranular zone. A key finding is that T3, the biologically active form of THs, promotes NSC commitment toward a neuronal fate. In this review, we first discuss the roles of THs in the regulation of adult rodent neurogenesis, as well as how it relates to functional behavior, notably olfaction and cognition. Most research uncovering these roles of TH in adult neurogenesis was conducted in rodents, whose genetic background, brain structure and rate of neurogenesis are considerably different from that of humans. To bridge the phylogenetic gap, we also explore the similarities and divergences of TH-dependent adult neurogenesis in non-human primate models. Lastly, we examine how photoperiodic length changes TH homeostasis, and how that might affect adult neurogenesis in seasonal species to increase fitness. Several aspects by which TH acts on adult NSCs seem to be conserved among mammals, while we only start to uncover the molecular pathways, as well as how other in- and extrinsic factors are intertwined. A multispecies approach delivering more insights in the matter will pave the way for novel NSC-based therapies to combat neurological disorders.
... As such, they are noxious and impair the overall cognitive performance of the individual as well as their affective sensitivity. Both of them have negative consequences, although overvalued ideas could sometimes have a positive outcome (Previc, 2009); it always depends on the given case and context. The possible continuum formed by these ideas is of big interest, specifically at the point where the overvalued ideas are transformed into delusions or the other way round-namely when delusions lose their affective power, start to dissolve and are transformed into delusion-like ideas. ...
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Abstract: In clinical practice, there is a need for a search for shortened, reduced forms of methodologies that have sufficient internal consistency indicators, while not excessively aggravating the specific process of clinical psychological research. The purpose of this report is to present data from a short battery study for intelligence research in children with mental and behavioral disorders - a clinical sample. The necessity of such a methodology stems from the practical aspects of the clinical and psychological research, where a large number of the standardized methodologies prove to be unusable. The sample was formed by 489 children who passed through the Children's and Adolescent psychiatric Clinic at St. Marina-Varna Hospital for a period of nine years (2010-2018). Data on internal consistency of the scale, external validity, correlation between sub-tests are presented.
... However, it is also observed that though anticipated, there exists no significant correlation between 'Locus of control' and performance on 'deception task'. Such a relationship was hypothesized because the internal-external LOC dimension has been considered as generalized measure of cognitive self regulatory capacities (Previc, 2009). There exists a statistically significant positive correlation (p < 0.05) between 'neuroticism' and performance on 'deception task' implying that a difficulty in suppressing the truth is associated with emotional instability. ...
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The present study aims to explore the cognitive basis of self-deception on the basis of the participants’ performance on a deception task and its relation to other cognitive variables. A total of 130 healthy participants (58 males and 72 females) of the age range of 18-25 years having a minimum educational qualification of ‘passed grade XII’ were screened and selected for the study using General Health Questionnaire 28. By using an interview format, the researcher collected personally significant information from the participants to be used later in the deception task. An android based mobile application was prepared to generate and administer the deception task. The participants were also assessed on Stroop Task (www.onlinestrooptest.com), Eyesenck Personality Questionnaire (1975), Rotter’s Locus of Control Scale (1954), Rosenberg’s Self Esteem Scale (1965) Generalized Self Efficacy Scale (Schwarzer, R. and Jerusalem, M., 1995). Statistical analysis revealed self-deception is related to personality and cognitive inhibition. The results were discussed in light of recent literature.
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1. Характеристики на креативността 2. Когнитивна невропсихология на креативността 3. Когнитивна невронаука на креативността: фокус върху допаминергичните мозъчни системи 4. Large-scale brain networks 5. Граничната ситуация у Карл Ясперс 6. Третичен мисловен процес 7. Ролята на психеделиците при креативността: психофармакология 8. Любопитство и креативност 9. Миниатюра на гранична ситуация 10. Динамика на третичния мисловен процес в миниатюрата на граничната ситауция: Континуум от преживявания
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Neuropharmacological effects of psychedelics have profound cognitive, emotional, and social effects that inspired the development of cultures and religions worldwide. Findings that psychedelics objectively and reliably produce mystical experiences press the question of the neuropharmacological mechanisms by which these highly significant experiences are produced by exogenous neurotransmitter analogs. Humans have a long evolutionary relationship with psychedelics, a consequence of psychedelics' selective effects for human cognitive abilities, exemplified in the information rich visionary experiences. Objective evidence that psychedelics produce classic mystical experiences, coupled with the finding that hallucinatory experiences can be induced by many non-drug mechanisms, illustrates the need for a common model of visionary effects. Several models implicate disturbances of normal regulatory processes in the brain as the underlying mechanisms responsible for the similarities of visionary experiences produced by psychedelic and other methods for altering consciousness. Similarities in psychedelic-induced visionary experiences and those produced by practices such as meditation and hypnosis and pathological conditions such as epilepsy indicate the need for a general model explaining visionary experiences. Common mechanisms underlying diverse alterations of consciousness involve the disruption of normal functions of the prefrontal cortex and default mode network (DMN). This interruption of ordinary control mechanisms allows for the release of thalamic and other lower brain discharges that stimulate a visual information representation system and release the effects of innate cognitive functions and operators. Converging forms of evidence support the hypothesis that the source of psychedelic experiences involves the emergence of these innate cognitive processes of lower brain systems, with visionary experiences resulting from the activation of innate processes based in the mirror neuron system (MNS).
Article
A recurrent mantra of the technology industry is that all forms of ‘friction’ should be eliminated from online interactions (especially commercial transactions). In this context, ‘friction’ refers to any unnecessary retardation of a process or activity that delays the user accomplishing a desired action. This broad category can therefore include online adverts that link to the wrong webpages, pop-up windows that block access to content or delays in the physical delivery of an ordered item. Although visions of a frictionless future have been common since at least 1995 (the year Bill Gates popularised the phrase ‘friction-free capitalism’), the basic notion has remained unhelpfully vague. Accordingly, this article focuses specifically on the phenomenon of online friction (i.e. ‘e-friction’) and elaborates a typology of the main subtypes. An analytical framework of this kind makes it much easier to compare and contrast distinct kinds of e-friction, recognising that important differences distinguish those that are ‘elective’, ‘non-elective’, ‘impeding’, ‘distracting’ and so on. Having sketched a preliminary typology, the article reflects upon the ethical implications of the distinct varieties, and concludes by suggesting that there are several reasons why an entirely (e-)frictionless future is a profoundly disturbing one.
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Creativity is one of the areas which continuously attracts attention. In an interdisciplinary spirit, this article focuses on the dynamics of creativity with respect to Freudian psychoanalytical thought processes and Jaspers’ conception of a boundary situation. This effort is correlated with the newest research findings in cognitive neuroscience and neurocognitive psychology of creativity. Philosophical research is also brought in to explain the activity of creative thought and a new conception of creativity is offered, with a third thought process used, along with a miniature boundary situation. This represents a development and extension of the original ideas of Sigmund Freud and Karl Jaspers. The current article thus constitutes an examination of the intersection of creativity research, the metapsychology of Sigmund Freud, and the existential philosophy of Karl Jaspers. It makes it a neuro-philosophical discussion par excellence and represents both a theoretical project and translation. Subsequently, a novel conception is offered, namely that creativity as unique human experience is illuminated in the miniature of boundary situation as controlled disinhibition of the intellect or regression in the name of the ego and as controlled spiral movement via dialectical “jumps” or “leaps.”
Chapter
The building blocks of all cells and the mechanisms by which they communicate with each other are central to the study of cognition. The complexity of the brain is readily apparent at the macroscale level and mesoscale level, with ~100 billion neurons and ~100,000 miles of connectivity fibers. However at the microscopic level there is an equally impressive intracellular and intercellular complexity. Cognitive and behavioral neurological syndromes may often be due to a chemical, a receptor, or other neurochemical perturbation. The brain functions as an electrochemical organ and many cognitive syndromes may be deciphered at the synaptic or intracellular level. A rudimentary knowledge of the basic cellular components, molecular constituents, neurotransmitters, receptors, and multiple levels of messenger systems is important in understanding and treating cognition. Neurochemistry is a mere subset of organic chemistry, which in turn is a part of chemistry in the wider context. A basic knowledge of neurochemistry and classification system of the various components is helpful in understanding many neurological and cognitive disorders such as seizures and autoimmune encephalopathy. This brief overview is not comprehensive and for more in-depth neurochemical insights the reader is referred to the excellent treatises by Brady, Nestler, Stahl, Harper, and Ganong that served as reference sources for this brief review [1–5].
Article
The findings of modern brain research have not been incorporated into research on creativity (Dietrich, 2004, p. 1011), or have been , but to a minor extent. Therefore, the shedding of additional light, in accordance with the newest findings in (cognitive) neuroscience, in particular the relationship between the dopaminergic neurotransmission in the brain and creativity (as hypothesized and subsequently established by Takeuchi et al. (2010)), would provide an up-to-date bottom-up neurobiological account of how creativity is mediated by the brain. This would also assist in the debates on the conceptual definition of creativity.
Chapter
The chapter begins with the premise: could we have remained a society devoid of technology? Loaded with neurotransmitters that contribute to search behavior and lead to goal-directed behavior, human beings tend to gain mastery over their environment. It would not be an exaggeration to contend that we are born to choose and create choices that lead to enhance our adaptability. Going beyond this specific domain might result in creation of myriad choices that could result in exaptation. Engaging in technology, thus, leads to the augmentation of adaptation and exaptation, and in many ways enables us to conclude that human activity and any use of technology appear to be inseparable in many cases. This is not just peculiar to human beings, for animals and other organisms have been found to employ technology as per their capacity, albeit dictated by their physical features and limitations. That said, the chapter invites the reader to consider the creation and use of things around us, for example, the dimensions of things ranging from those at home to those placed in other environments including those used in various cultures. Beginning with general issues that are common in the study of anthropometry, such as the structural and functional aspects of our physical dimensions in the context of how one size fits all, the chapter describes how growth in the field of ergonomics, particularly in the neurological context, has contributed to our understanding of psychology at work, an important subtopic of psychology of technology. This chapter has been written for both academic and applied professionals in particular and the layperson, in general, to appreciate how integration of our knowledge of biology, technology, and psychology has been helpful in contributing to the continuous growth of anthropometry and ergonomics and how such growth offers insights into redesigning workplaces for the elderly, developing interactive tools, looking beyond mere physical dimensions in creating things around us, designing for special conditions such as the space capsule, and in short, almost everything around us that is meant for our use.
Chapter
Neuroeconomics is an emergent multidisciplinary field that strives to understand how and why humans make decisions. The field brings together behavioral methods and sophisticated computational theories from microeconomics, an understanding of emotional influences on behavior from psychology, and human functional neural imaging from neuroscience. This chapter presents the fundamentals of neuroeconomics, thus describing the concept of neuroeconomics; neuroimaging applications; neuroeconomics and loss aversion; neuroeconomics and temporal discounting; neuroeconomics of decision making in humans and animals; neuroeconomics, behavioral economics, and irrationality; neuroeconomics and utility theory; neural systems in economic decision making; neural systems in reward system; neural systems in cognitive control system; game theory, strategic interaction, and neuroeconomic studies; and the types of evidence about economic behavior.
Thesis
Настоящият труд включва философско и научно изследване на креативността във феномена „гранична ситуация“, както е развит във философията на Карл Ясперс. Трудът е разделен на три части: 1) Въведение във философията на Карл Ясперс и концепцията за „гранична ситуация“, 2) Описание на функциите на психо-соматичния комплекс в норма и патология и техните отношения към философията и философското съзнание и 3) Изследване на креативността преди, по време и след преживяванията на гранични ситуации. Първата част е историко-философска. Втората – научна, а третата е синтез между първите две, като двете линии – философската и научната – са развити паралелно. Използваните методи са: историко-философски анализ, сравнителен анализ, концептуален анализ. Излагат се редица подстъпи към едно сериозно изследване на граничните ситуации и на ролята на креативността по отношение на методите за тяхното превъзмогване. Включени са редица изследвания в рамките на конкретни области от познанието, свързани с ядрената тематика труда, като: понятието „креативност“, епилепсията на Достоевски, животът на Е. Сведенборг, фармакометафизиката, депресивно-песимистичния реализъм, психичните защити по А. и З. Фройд, понятието „Аз“, логотерапията на В. Франкъл, психозомиметиците и др. Фокусът е върху способите за превъзмогване на граничните ситуации, в частност каква роля играе креативността при тях. Предлага се богата съвкупност от перспективи за бъдещи изследвания в горепосочените области и проблемни точки. Глава 1: Понятието „гранична ситуация“ в екзистенциалната философия на Карл Ясперс В тази глава се анализира понятието „гранична ситуация“ в рамките на философията на Карл Ясперс или т. нар. Existenzphilosophie. Става въпрос не за вид екзистенциална философия, а за философия на Existenz. Разгледани са в детайли основните понятия на Existenzphilosophie, а именно: Всеобхватно, Existenz, Transcendenz, Разум, Операцията „трансцендиране“, Крушение и Философска вяра. Понятието „гранична ситуация“ е дискутирано, от тази перспектива, в следните главни точки: Същност, Кой попада в гранична ситуация?, Методи за превъзмогване (вж. Глава 3), Гранични ситуации и психопатология, Видове гранични ситуации и Навлизане в гранични ситуации. Разгледано е и понятието „мистично преживяване“ в рамките на Ясперсовата Existenzphilosophie. Приведени са голямо количество цитати от основните трудове на Ясперс (от преводите от немски на английски език), които не са преведени на български език и които сами по себе си представляват една миниатюрна антология на Ясперсовата Existenzphilosophie. Глава 2: Науката на психо-соматичния комплекс срещу философското съзнание В тази глава изложението включва главно дискусията на научни понятия и концепции, но са дадени и редица философски такива. Ясперс е считал, че за философстващия са от ключово значение наличните обширни научни познания. Това е така поради факта, че самата Existenzphilosophie или философската светова ориентация, така да се каже, надгражда научния светоглед или т. нар. от Ясперс научна светова ориентация. Поради този факт, главата започва с дискусия върху отношението, взаимовръзката и взаимоотношението между науката и философията. След това в детайли е анализирано понятието „съзнание“, както от научна, така и от философска перспектива. На читателя се предоставя и кратка научна дискусия върху функционалността на човешкото съзнание и човешката психика в норма и в патология; тук е включено и изложение върху т. нар. механизми за психична защита по А. и З. Фройд. Главата завършва с кратко изложение на главните постановки в когнитивната наука, вкл. и афективната наука: възприятие, познание, емоции и деятелност. Включено е и изложение, което представлява кратко въведение в основите на функционалната невроанатомия, както и основните принципи на невро- и психофармакологията. Емоционалността или афективността е разгледана и от философска перспектива в лицето на т. нар. екзистенциални чувства. Главата завършва с кратко, но богато изложение върху психологията и философията на креативността. Глава 3: Динамика на креативността във феномена „гранична ситуация“ Тази глава се базира на Глава 1 и Глава 2, като представлява синтез между двете глави. Фокусът е върху динамиката на креативността, която се анализира в рамките на преживяванията на гранични ситуации. Приведен е списък с възможните методи за превъзмогване на граничните ситуации, който е далеч по-пълен от този, представен в съответната секция в Глава 1. Разгледан е случаят със SARS-CoV-2 като актуална световна гранична ситуация. Впоследствие се въвежда понятието „миниатюра на гранична ситуация“, което представлява смес между креативността като процес (и черта) и граничните ситуации – самата креативност се разглежда като миниатюра на гранична ситуация. Към всичко това, ние сме привели и следните дискусии (като вид практическо приложение на знанието за граничните ситуации): Логотерапията на Виктор Франкъл (и изобщо екзистенциалната психотерапия) като метод за превъзмогване на граничните ситуации, Феноменология на психеделичното състояние (като метод за превъзмогване на гранични ситуации и като метод за индуциране на гранични ситуации, респ. мистични преживявания), Видовете светогледи и граничните ситуации – в частност т. нар. от нас Депресивно-песимистичен реализъм, Философията на човешкото когнитивно фармакологично подобрение – Фармакометафизика и граничните ситуации, Екстазната аура като мистично преживяване при епилепсията на Достоевски и граничните ситуации (вж. секцията за мистичното преживяване в Глава 1), Метафизиката на душата като парафрения на психиката – случаят на Емануел Сведенборг – граничните ситуации и обективацията на езика на Трансценденцията.
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Evaluation of cognitive function or assessment of mentation in those with symptoms, or reported by friends or family, has many challenges. A particularly flexible approach is required, as some people cannot even be assessed due to obtundation, some cannot concentrate for more than a few seconds in the case of delirium, and some are inattentive with only minutes of assessment possible (dementias). Extensive in-depth neuropsychological testing at the other extreme is taxing even for normal people. Furthermore, examination technique may be prone to error and misinterpretation, by many factors, including medications (the ubiquitous anticholinergic drug effects) and organ system failure (minimal hepatic encephalopathy). In addition, overdiagnosis of cognitive deficits is not uncommon, even by experienced neuropsychologists [1].
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Empirical cross-cultural research provides a typology of magico-religious practitioners and identifies their relations to social complexity, their selection-function relationships, and reveals their biosocial bases. Different practitioner types and configurations are associated with specific ecological and political dynamics that indicate a cultural evolutionary development. Relations between practitioners’ selection processes and professional activities reveal three fundamental structures of religions: (1) selection and training involving alterations of consciousness used for healing, manifested in Shamans and other shamanistic healers; (2) social inheritance of leadership roles providing a hierarchical political organization of agricultural societies, manifested in Priests; and (3) attribution of a role involving inherently evil activities, and manifested in the Sorcerer/Witch. Shamans were transformed with foraging loss, agricultural intensification, warfare, and political integration into Healers and Mediums. Priests are predicted by agriculture and political integration beyond the local community, representing the emergence of a new stratum of magico-religious practice. Priests are also responsible for political and social conditions that significantly predict the presence of the Sorcerer/Witch. These findings suggest three distinctive biosocial structures of magico-religious activity related to alterations of consciousness and endogenous healing processes; hierarchically integrated social organization; and social persecution and incorporation.
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Children may be differently affected by environmental influences. The aim of the current thesis was to examine how children’s genotype interacts with various environmental factors in the development of social behavior and relationships. In two of the three papers (papers II and III), we tested whether some children are merely vulnerable to adversity (diathesis stress), or, susceptible to negative and positive environmental influences (differential susceptibility). The data applied in this thesis stem from the Norwegian longitudinal cohort study, the Trondheim Early Secure Study (TESS). The sample included 704 children genotyped for catechol-O-methyltransferase Val158Met (COMT, rs4680) and 652 genotyped for the oxytocin receptor gene (OXTR, rs53576). Children ages four (T1), six (T2), and eight years (T3) were examined. The results of the first study demonstrated that children’s genotype (COMT) moderated the effect of disorganized attachment over time (from four to six years) on social behavior (aggression and social competence). More specific; children who scored high on disorganization and were carriers of Valine/Valine (Val/Val), showed significantly greater increases in aggression over time compared to highly disorganized children carrying the methionine (Met) allele. Met carriers who were highly disorganized, increased their social competence (other-oriented) more than disorganized Val homozygotes. The results were interpreted to reflect two distinct developmental trajectories disorganized children usually follow: controlling-punitive and controlling-caregiving. In study II, the results showed that COMT moderated the effect of serious life events on aggression. Some children depending on genotype (Val/Val) displayed the highest aggression scores in the presence of serious life events but the lowest aggression scores in the absence of such events. The findings conformed to the differential susceptibility hypothesis. Finally, the results from paper III revealed that change in parenting, from four to six years, predicted change in the student-teacher relationship, from six to eight years, for children with a specific genotype of OXTR rs53576; when parenting changed for the better, the teacher-child relationship improved accordingly. When parenting changed for the worse, the student-teacher relationship also changed for the worse. The findings conformed to the differential susceptibility framework.
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Neuroeconomics is an emergent multidisciplinary field that strives to understand how and why humans make decisions. The field brings together behavioral methods and sophisticated computational theories from microeconomics, an understanding of emotional influences on behavior from psychology, and human functional neural imaging from neuroscience. This chapter presents the fundamentals of neuroeconomics, thus describing the concept of neuroeconomics; neuroimaging applications; neuroeconomics and loss aversion; neuroeconomics and temporal discounting; neuroeconomics of decision making in humans and animals; neuroeconomics, behavioral economics, and irrationality; neuroeconomics and utility theory; neural systems in economic decision making; neural systems in reward system; neural systems in cognitive control system; game theory, strategic interaction, and neuroeconomic studies; and the types of evidence about economic behavior.
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This review illustrates the relevance of shamanism and its evolution under effects of psilocybin as a framework for identifying evolved aspects of psychedelic set and setting. Effects of 5HT2 psychedelics on serotonin, stress adaptation, visual systems and personality illustrate adaptive mechanisms through which psychedelics could have enhanced hominin evolution as an environmental factor influencing selection for features of our evolved psychology. Evolutionary psychology perspectives on ritual, shamanism and psychedelics provides bases for inferences regarding psychedelics’ likely roles in hominin evolution as exogenous neurotransmitter sources through their effects in selection for innate dispositions for psychedelic set and setting. Psychedelics stimulate ancient brain structures and innate modular thought modules, especially self-awareness, other awareness, “mind reading,” spatial and visual intelligences. The integration of these innate modules are also core features of shamanism. Cross-cultural research illustrates shamanism is an empirical phenomenon of foraging societies, with its ancient basis in collective hominid displays, ritual alterations of consciousness, and endogenous healing responses. Shamanic practices employed psychedelics and manipulated extrapharmacological effects through stimulation of serotonin and dopamine systems and augmenting processes of the reptilian and paleomammalian brains. Differences between chimpanzee maximal displays and shamanic rituals reveal a zone of proximal development in hominin evolution. The evolution of the mimetic capacity for enactment, dance, music, and imitation provided central capacities underlying shamanic performances. Other chimp-human differences in ritualized behaviors are directly related to psychedelic effects and their integration of innate modular thought processes. Psychedelics and other ritual alterations of consciousness stimulate these and other innate responses such as soul flight and death-and-rebirth experiences. These findings provided bases for making inferences regarding foundations of our evolved set, setting and psychology. Shamanic setting is eminently communal with singing, drumming, dancing and dramatic displays. Innate modular thought structures are prominent features of the set of shamanism, exemplified in animism, animal identities, perceptions of spirits, and psychological incorporation of spirit others. A shamanic-informed psychedelic therapy includes: a preparatory set with practices such as sexual abstinence, fasting and dream incubation; a set derived from innate modular cognitive capacities and their integration expressed in a relational animistic worldview; a focus on internal imagery manifesting a presentational intelligence; and spirit relations involving incorporation of animals as personal powers. Psychedelic research and treatment can adopt this shamanic biogenetic paradigm to optimize set, setting and ritual frameworks to enhance psychedelic effects.
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Gilles de la Tourette's syndrome (TS) is a familial disorder that is often exacerbated by stress or fatigue. Here we present a family of a TS proband that has several members with obsessive-compulsive symptoms, a bleeding disorder, and an unusual sensitivity to heat. The proband, who is affected by all of these traits, was challenged with heat or exercise in climate-controlled conditions and showed a marked increase in the frequency of tics.
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Results from a synthesis of correlations between psychometric intelligence and two physical traits, head size and body size, are reported. Within-family studies are reviewed for evidence of pleiotropy, the effect of a single genetic factor on two traits. Studies are also reviewed to determine whether prenatal effects bias twin studies, leading to underestimates of genetic influence. An N-weighted mean partial correlation (controlling height) of .10 between intelligence and head size was found. Using a method developed by Van Valen (1974), the correlation of intelligence and brain size was estimated as .29 based on all the intelligence/head-size studies of adults and adolescents, and .44 based on studies measuring intelligence with IQ tests. The N-weighted mean partial correlations (controlling age) of intelligence and height were .18 for children and .22 for adults. The within-family studies indicated that pleiotropy may contribute to the correlation of intelligence with head size and to the correlation of intelligence with body size. Prenatal effects are not an important source of bias in twin studies or for heritability estimates based on them.
Article
Clinically, adult autistic and PDD individuals appear to have an uneasy relationship with their social environment no matter how much developmental progress they make. Many can work at modest jobs, many more do not, and even fewer are interested enough in the human environment to cohabitate and/or marry. A conversation with a young autistic man of 20 about a trip to visit a relative focuses more on the time the train left and how late it was in hypermnestic detail, including all details except the affective environment or the relationships to human beings. This is the human significance of the term autism. Autistics can speak and reference, but they seem not to understand the social requirements of a human interchange. If they do know it, they know it in a fragmentary or rudimentary way devoid of subtlety or nuance. Whatever we mean by social intercourse and whatever functions subsume it, they seem to emerge in interaction with cognition and language. They develop apace as human traverse those first 3 years of life and as they reach social maturity in adolescence. Autistic children appear not to integrate their knowledge of things in a representation that includes emotional and cognitive elements. They do not seem to understand that words necessarily refer to things of this world that others are also referencing in their words and sentences--shared reference is not natural to them. Intersubjectivity as a feature of common code use is not tacit or explicit in their behavior. They similarly do not use social referencing in the way in which normals do, and although they show some attachment to people, they seem to do so without benefit of affective display leading to reciprocity. There is little notion of the external that makes another human being distinguishable from a thing. Their treasured objects in early childhood are hard and lack comforting proximal receptor attractiveness as in normals. Hobson's extensive studies have elaborated a notion about the autistic child's knowledge of person. He comments on the lack of integration of the verbal and visual situational ties in which affective expression emerges and functions. He also comments on the deictic inabilities, inferring that the "I," "you," and "he" references do not have any significance for such children. We would like to note that while Vygotsky and others have observed that speech comes from the world of people, language comes from the maturing organism as an innate propensity.(ABSTRACT TRUNCATED AT 400 WORDS)
Article
We tested the hypothesis that a special population of people who maintain exotic beliefs and report frequent subjective psi experiences should display more frequent temporal lobe signs and symptoms. Clusters of items, that reflect various temporal lobe factors for 20 women who were actively (greater than 1 year) involved with a local psychic and spiritual development group, were compared to items for an age-matched reference group (n = 61). T-scores for the reference group did not differ from those of the normal population. Whereas the psychic group did not differ from the reference group on various control and psychiatric measures, mean T-scores on clusters that infer complex partial epileptic signs (specifically a sense of presence, olfactory experiences, and intense meaning) ranged between 65 and 70. Group affiliation explained 22 to 50% of the variance for each of these variables; with discriminant analysis, they correctly classified 95% of both groups of participants.
Article
To assess the validity of Raven's Colored Progressive Matrices (RCPM) as a measure of intellectual impairment after focal brain damage, we compared the performance of 24 right brain-damaged patients, 24 left brain-damaged patients (10 non-aphasic and 15 aphasic) and 20 controls on the RCPM. In addition to the total, we analyzed the scores obtained on each of the three sets in which the 36 items of the test could be categorized on the grounds of the cognitive ability mainly involved for their solution. The first set, which calls for the identification of sameness, posed special problems to RBD patients. The second set, which involves the principle of symmetry, was selectively failed by aphasic patients. The third set, which is more demanding in terms of analogical and conceptual thinking, was poorly performed by left brain-damaged patients, aphasics as well as non-aphasics. The implications of these findings for the relation of focalized brain damage to intelligence is discussed.
Article
A variety of neurotransmitters have been implicated in the pathophysiology of chorea as exemplified by Huntington's chorea. These include dopamine, serotonin, acetylcholine, GABA and a variety of neuropeptides including substance P and somatostatin. Despite biochemical data that suggests that alterations in other neurotransmitters may be of greater significance, pharmacologic data still supports a major role of dopamine in the actual clinical manifestation of chorea.
Article
We present 8 cases of centrally-originating hyperthermic syndrome, the initial cause being either neuroleptic malingnant syndrome, hyperthemia after discontinuance of antiparkinsonian therapy or heatstroke. We review the physiological and neurochemical mechanisms involved in thermoregulation, emphasizing the role of dopamine. A single mechanism, consistent with pharmacological or neuropathological impairment of the dopaminergic system, could be responsible for all the cases of hyperthermic syndrome presented.
Article
The purpose of this study was to determine if combined therapy with dopaminergic drugs (DA), i.e. L-dopa or bromocriptine, and exogenous human GH (hGH) could increase growth velocity in hypopituitary children. Twelve prepubertal hypopituitary children (eight boys and four girls; bone age, 1.5-9.5 yr), divided into two groups, each received hGH alone, DA alone, and DA and hGH. Group I (n = 6) received L-dopa (15 mg/kg, orally) at 6-h-intervals during DA and combined DA and hGH therapy. Group II (n = 6) received bromocriptine (1.25 mg, orally) every 12 h during DA and combined DA and hGH therapy. Both groups were given hGH (0.1 IU/kg) three times per week during hGH and combined hGH and respective DA treatment. The study included three 6-month treatment periods of DA, hGH, and combined DA and hGH therapy. The mean growth rates (centimeters per 6 months, +/- SD) before treatment and during the three study periods for group I were 1.7 +/- 0.2, 3.3 +/- 0.8, 3.4 +/- 0.4, and 3.9 +/- 0.7, respectively. Group II results were 1.4 +/- 0.3, 2.3 +/- 0.8, 5 +/- 1.6, and 3.7 +/- 1.1. Mean and peak hGH concentrations, measured every 30 min for 9 h at the end of each study period, increased significantly in five patients, from 15 +/- 3 (+/- SE) ng/ml during hGH therapy to 30 +/- 5 ng/ml during DA and hGH treatment. The mean peak hGH values rose from 24 +/- 4 to 45 +/- 5 (+/- SE) ng/ml. In conclusion, addition of dopaminergic agents to hGH therapy potentiates growth in some hypopituitary children. The increased growth and hGH responses to L-dopa or bromocriptine suggest impaired endogenous GH release. Dopaminergic therapy alone or in combination with exogenous hGH may be efficacious in some hypopituitary children.
Article
Small but consistently positive correlations between standing height and general intelligence (the unrotated first principal component across the battery of cognitive tests) were found across sexes, racial/ethnic groups (Americans of European vs. Americans of Japanese ancestry), and generations in data from the Hawaii Family Study of Cognition. Sibling data produced significant height‐intelligence correlations for sibling pair means (i.e., between‐family differences) but not for within sibling pair differences. The lack of within‐family height‐intelligence correlations suggested that the two traits were linked due to cross‐assortative mating and/or between‐family environmental influences (e.g., nutrition) affecting both traits. Some evidence for both of these explanations was found.
Article
The 'psychic' experiences of 17 students (sensitives) from the College of Psychic Studies were compared with those of 17 church-going control subjects, who were matched for age, sex, and approximate intellectual level. At interview, 67 items of information relating to the medical history, family history, 'psychic gifts', head injuries, and mystical experiences were obtained. The shortened WAIS, the Benton Visual Retention Test, with tests of both dominant (Wechsler Logical Memory) and non-dominant temporal lobe function (the Rey-Osterreith Test) were given. The results showed that the sensitive population contained more single or divorced people, and people who had sometime consulted a psychiatrist. They had experienced more head injuries and serious illnesses than the controls. Sixty-six per cent showed evidence of right hemisphere and right temporal lobe dysfunction and, of these, 35 per cent had poor visual memories. There was evidence to suggest that some 'psychic' experiences were associated with brain dysfunction. Despite an increased occurrence of head injury, no clear correlation with the onset of 'psychic' sensitivity was found. Mystical experiences showed a trend towards being related to non-dominant hemisphere dysfunction. Vagueness about the position of the sensitive's 'psychic helper' in physical space was also associated with non-dominant hemisphere dysfunction.
Article
The role of serious-mindedness (so-called telic dominance) in regulation of parietal cortex EEG was investigated. Ten telic (serious-minded) and 10 paratelic (playful state-dominant) individuals were selected on the basis of their responses to the Telic Dominance Scale. They all performed instructed breathholding (hypopnea) and excessive breathing (hyperpnea) in counterbalanced order. The paratelic individuals yielded relatively high scores of integral EEG power; theta power was markedly increased in the left hemisphere during hyperpnea, and reduced in the right hemisphere during hypopnea. Both hyperpnea and hypopnea were reported to be more aversive to the paratelic than to the telic subjects, but no group difference in respiratory activity was found. The electrocortical and hedonic tone differences between the groups are discussed in relation to the distinction between the prefrontal (dopamine) activation pathway and frontoparietal (noradrenalin) arousal pathway, as well as in relation to changes in cortical blood flow and proprioceptive feedback.
Article
Following surgical division of the neocortical commissures in humans, it is possible to test independently the 2 cerebral hemispheres on the same task and thus determine directly their competence for various cognitive skills. Studies examining the limits of language expression and comprehension in the minor hemisphere of these patients are reviewed. Evidence of right-hemispheric superiority for the perception of spatial and part-whole relations is discussed with respect to theories postulating a basic dissimilarity in the manner by which information is processed in the major and minor hemispheres. Data are also reviewed which suggest that competition between the 2 hemispheres for control of the motor system is resolved in favor of the hemisphere dominant for the cognitive function required in the task. (41 ref)
Article
The effect of six acute doses of the dopamine receptor agonist apomorphine on non-human primate social and individual behaviour was studied in a social colony of four adult Stumptail macaques. Apomorphine was administered intramuscularly to 2 monkeys/day in doses ranging from 0.05 to 3.00 mg kg-1 15 min bfefore a 1 h observation period. Apomorphine induced hyperactivity, hypervigilance, and stereotyped behaviour at doses of 0.50 mg kg-1 and greater in all 4 monkeys. In addition it also caused a dose-dependent disruption of normal behavioural patterns. Social grooming was eliminated while the submissive gestures were significantly increased. It also induced an increase in vocalizations and suppression of food forage behaviours. The results demonstrate the role of dopamine systems in the mediation of affiliative behaviour as well as motor behaviour in a primate species. Also, since similar behavioural changes are induced in this species during chronic (+)-amphetamine treatment, it is suggested that dopamine systems play a predominant role in amphetamine-induced behaviour in primates.
Article
Religious dreaming is as universal an experience as dreaming. But, unlike the ancients who interpreted their religious dreams in context of their religious views, contemporary man has been too shackled by scientific materialism to fully appreciate religious dreams. I have presented a review of some contemporary observations on religious dreams, and presented two clinical cases and current dream material to show that we still can harness the power of religious dreams. Religious images and symbols in dreams can provide a source for growth and health today as they did in ancient times. When the outer religious symbols of groups lose their effectiveness in our lives, inner religious symbols as seen in dreams can become more effective in human life. The need to work with religious images and symbolism is indicated.
Article
Religious and god-related experiences have been hypothesized to be a portion of the continuum of phenomena that are generated by endogenous, transient electrical stimulation within deep structures of the temporal lobe. According to this hypothesis, normal people, without psychiatric history, who report intense religious experiences should also demonstrate a wide range of temporal lobe-related private behaviors. To test this prediction, a self-report inventory that contained 140 temporal-lobe-relevant information, opinion-belief, and sampled MMPI statements was administered to two separate groups (n = 108; n = 41) of male and female first-year university students. In Study I, subjects who had reported religious experiences, particularly those who did not attend church regularly, scored significantly higher on a variety of statement clusters (n = 7 to 14 items) that contained temporal-lobe symptomology relative to groups who did not report religious experiences and did not attend church regularly. In Study II subjects, regardless of church attendance, who reported religious experiences scored significantly higher on the temporal-lobe clusters. People who reported religious experiences were more likely to have kept a dairy and to enjoy poetry reading or writing. However, religious experiments and churchgoers did not score higher (in either experiment) on clusters that contained mundane psychological or proprioceptive statements, descriptions of odd sensations, or modified portions of the Lie scale from the MMPI.
Article
After ablation of mesolimbic and mesocortical dopaminergic neurons produced by 6-hydroxydopamine (6-OHDA) injections in the anterolateral hypothalamus, rats investigate a novel object less. Systemic administration of the dopamine (DA) agonist apomorphine increases investigatory movements in these DA-denervated rats when the object is novel, but not when the object is familiar. Pimozide pretreatment prevents the increased investigation produced by apomorphine in DA-denervated rats. These findings suggest that mesolimbic and mesocortical DA neurons are necessary for normal exploratory behavior in the rat.
Article
To test whether laterality of parietal lobe cerebral functioning might relate to a history of violent behavior, a sample of 33 male and female, right-handed juvenile offenders, divided into less and more violent, each performed the Weighs Test. A lateralization index (left-hand score divided by right-hand score) formed the dependent variable. Differences for sexes and ages, but not ethnicities, required corrections. As hypothesized, poorer right- than left-parietal function related positively with the violence of past crimes. A sample of 18 additional subjects replicated the findings. The results were discussed in terms of a concept of cerebral "area-appropriateness," so that when the task-appropriate area performs less well than a less-appropriate area, we may begin to infer a dysfunction which may relate to "dyscontrol" and to violent behavior.
Article
We describe a new deafness mutant found in the Zucker rat. The mutant phenotype appears to be caused by an autosomal recessive gene, tentatively named stargazer, gene symbol stg. The phenotype is characterized by stargazing, head tossing, drawing back, circling, and hyperactivity, all of which are apparent by the third week of life. Although the affected animals sire or bear normal-sized litters, mortality is high for litters of affected dams, apparently due to trampling or neglect by the hyperactive dams. Affected animals are unable to swim and, when lifted by the tail, they are likely to curl ventrally, rather than extending their paws downward. These behaviors are consistent with a disorder of the vestibular system. Auditory evoked potential recordings were attempted as a hearing test. The failure of audible clicks up to 90 decibels to stimulate the auditory tract indicates that stargazers are profoundly deaf. These disruptions of vestibular and auditory systems suggest that the stargazer phenotype may be caused by disordered development of the inner ear. Histologic examination of the inner ear revealed progressive degeneration of cells in the acoustic ganglion and of hair cells. The stargazer rat may be useful as a model for hereditary deafness or hyperactivity.
Article
The present study examined both dispositional and behavioral indices of future and present temporal perspective as measured by the 1985 Gonzalez and Zimbardo scale. To examine the behavioral consequences of individual temporal perspective, the 1988 Robinson method of time diaries was used. Four dispositional indices and their association with individual temporal perspective were examined, need for achievement, work ethic orientation, self-monitoring, and evaluation anxiety. Individuals with a future time perspective placed a strong emphasis on success via goal-directed behavior, paid attention to environmental cues, and engaged in a large number of activities to achieve these goals. Implications for research are discussed.
Article
This study extends earlier findings of poorly facilitated postexercise heat loss during the winter in seasonal affective disorder (SAD). While depressed in the winter, 19 SAD subjects exhibited a significantly impaired postexercise heat loss relative to 10 control subjects. During the summer while euthymic, SAD subjects did not significantly differ from control subjects in postexercise heat loss. Since thermoregulatory heat loss is a highly dopamine-dependent process, these results support earlier findings of poorly facilitated dopamine availability in SAD during the winter and suggest a centrally mediated effect of light in SAD.
Article
In an attempt to investigate whether auditory lateralization has a heritable component, 20 monozygotic (MZ) twin pairs were examined with four different dichotic listening tests known to produce reliable right-ear advantages (REAs) in right-handers. Ten twin pairs were concordantly right-handed (MZ-RR), and ten twin pairs were discordant for handedness (MZ-RL). Intraclass correlations for MZ twin pairs were weak or nonexistent for ear advantage, but relatively strong for overall correct scores and mean reaction times, measures unrelated to laterality scores. These results support the hypothesis that auditory lateralization, as measured with dichotic tests, is nongenetic in origin. A comparison of MZ twins and right-handed siblings (n = 20) showed that right-handed siblings exhibited strong REAs, whereas left-handed siblings (n = 20) and MZ twins showed weak or absent REAs, indicating that twins may be atypically lateralized with respect to auditory lateralization.
Article
Based on our data, the clinical picture of endemic cretinism results from the product of two pathophysiological events. Both events share a common feature, namely iodine deficiency, but act at different points in time. The first event occurs in all cretins and represents the prenatal action of thyroid hormone deficiency on brain development, transmitted vertically from mother to fetus, resulting in the neurological disorder of endemic cretinism. A consistent pattern and intensity of neurological, intellectual, and audiometric deficit is common to and equally present in all types of endemic cretin. The nature of these deficits points to an intrauterine insult to the developing fetal nervous system around the time of the midtrimester. The second event represents the postnatal action of thyroid hormone deficiency on somatic as well as brain development. Whereas previous workers had attributed the differences in the clinical presentation of endemic cretinism to the presence or absence of neurological features (i.e. prenatal hypothyroidism), the distinction between the types of endemic cretin can be related to the length and severity of postnatal thyroid hormone deficiency. Endemic cretins with predominant neurological features have had only transient hypothyroidism in the postnatal period, evidenced by their near normal thyroid function and by a lack of hypothyroid clinical features. By contrast, cretins with marked myxedematous features were characterized by permanent and severe postnatal thyroid hormone deficiency. These cretins, in addition to signs of neurological damage, were typically dwarfed, sexually immature, with marked clinical features of myxedema. This second event, influenced by the thyroid gland's morphologic response to its environment (goiter or thyroid atrophy), dictates the final clinical outcome. In conclusion, our hypothesis states that the clinical expression of endemic cretinism is determined by the sum of two pathophysiologic processes. The first process is fetal hypothyroidism which results in the neurological damage of the disorder and the second process is the duration and magnitude of postnatal hypothyroidism which dictates the final clinical appearance.
Article
Dreaming is characterized by formal visual imagery (akin to hallucination), by inconstancy of time, place and person (akin to disorientation), by a scenario-like knitting together of disparate elements (akin to confabulation) and by an inability to recall (akin to amnesia). Taken together, these four dream features are similar to the delirium of organic brain disease. By studying the brain during rapid-eye-movement (REM) sleep--the phase of sleep in which most dreaming occurs--we can begin to understand its basis in the altered neurophysiology of REM.
Article
Attitudes to dream evaluation vary depending on culture. Dreams are considered important, real, and public in some cultures, but absurd, irrational and personal in others. Japan has its own history of dreaming, which can be well reconstructed due to rich sources of archeological and documentary material. In this paper dream evolution in Japan is described. Phase 1 is the prehistoric Jomon period, where people believed dreams were part of reality. From Phase 2, the sophisticated philosophies of Confucianism, Buddhism and Taoism were introduced and changed the social and mental system of Japan in phase 3. At phase 4, the amalgamation of local and alien cultures occurred and supernatural beliefs prevailed. In this society dreams played a very important role. Phase 5 is the period when the Samurai class ruled Japan. The pragmatic thinking of the Samurai succeeded in fostering good preconditions for the receipt of scientific Western culture in phase 6. The importance of dreams in Japan evolved in such a way. However, the elements of each phase continued and accumulated similar layers. Thus, a majority of the phases seemed to retain animism from the Jomon period.
Article
Established efficacy and tolerability in large multicentre controlled studies have made serotonin (5-hydroxytryptamine; 5-HT) reuptake inhibitors (SRIs) the mainstay of monotherapy for adult obsessive-compulsive disorder (OCD). When compared with the selective serotonin reuptake inhibitors (SSRIs), the tricyclic compound clomipramine has a higher incidence of adverse effects but is well tolerated by most OCD patients and may confer the best overall antiobsessional effects. Consideration of specific adverse effect profiles, special patient population characteristics, drug interactions and relative cost of the various agents may direct clinicians in choosing the most appropriate first-line drug. Alternative agents as monotherapies have been explored, but none has consistently proven effective to date. Investigations of SRI augmentation with serotonin-enhancing agents have also failed to demonstrate substantial benefits for treatment-refractory OCD. Combination treatment with SRIs and dopamine receptor antagonist drugs appears to provide an improved response for the subpopulation of OCD patients who have comorbid ‘tic-spectrum’ disorders, though large-scale studies of the efficacy and tolerability of these regimens are not yet available.
Article
Data obtained from a sample of 102 university students were used to calculate Pearson product moment correlations between measures of complex partial epileptic signs, peak experiences and paranormal beliefs. Significant correlations ranging from .35 to .42 (p < .001) were found between all three measures. Moreover, notable relations were obtained between complex partial epileptic signs and a number of subscales of the paranormal measure including precognition (r = .43), psi beliefs (r = .40), spiritualism (r = .40), extraordinary life forms (r = .26) and superstition (r = .22). The results are consistent with previous research linking temporal lobe signs to paranormal and peak experiences.
Article
This paper presents an overview of the recent literature on the association between prenatal and perinatal complications (PPCs) and schizophrenia, then systematically reviews papers published later than 1965 examining the association of PPCs and bipolar disorder. Three of the four studies comparing bipolar cases with normal controls indicated a positive association of PPCs with the development of bipolar disorder in adult life; the four odds ratios ranged from 1.0 to 12.0. The proportion of PPCs among the bipolar samples without comparison subjects ranged from 3.8% to 50.0%. Issues of study design, measurement and severity of exposure, and outcome are addressed. This review suggests that further investigation of genetic interactions, gender differences, and the specificity of effects in the association between PPCs and mental disorders other than schizophrenia is warranted.