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Individual Differences in Extraversion and Dopamine Genetics Predict Neural Reward Responses

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Abstract

Psychologists have linked the personality trait extraversion both to differences in reward sensitivity and to dopamine functioning, but little is known about how these differences are reflected in the functioning of the brain's dopaminergic neural reward system. Here, we show that individual differences in extraversion and the presence of the A1 allele on the dopamine D2 receptor gene predict activation magnitudes in the brain's reward system during a gambling task. In two functional MRI experiments, participants probabilistically received rewards either immediately following a behavioral response (Study 1) or after a 7.5 s anticipation period (Study 2). Although group activation maps revealed anticipation- and reward-related activations in the reward system, individual differences in extraversion and the presence of the D2 Taq1A allele predicted a significant amount of inter-subject variability in the magnitudes of reward-related, but not anticipation-related, activations. These results demonstrate a link between stable differences in personality, genetics, and brain functioning.

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... There is also relatively consistent evidence of associations between the dopamine receptor DRD2 gene and activation of VS/DS to rewards (Cohen et al., 2005;Felsted et al., 2010;Forbes et al., 2009;Richter et al., 2017), with some exceptions (Peciña et al., 2013). Two studies indicated that the presence of the Taq1A A1 allele is associated with reduced PVS function, including reduced VS activation (Cohen et al., 2005;Felsted et al., 2010). ...
... There is also relatively consistent evidence of associations between the dopamine receptor DRD2 gene and activation of VS/DS to rewards (Cohen et al., 2005;Felsted et al., 2010;Forbes et al., 2009;Richter et al., 2017), with some exceptions (Peciña et al., 2013). Two studies indicated that the presence of the Taq1A A1 allele is associated with reduced PVS function, including reduced VS activation (Cohen et al., 2005;Felsted et al., 2010). Another study found links between the Taq1A A1 allele and better performance on a recognition memory J o u r n a l P r e -p r o o f following an incentive task, but only the c957T polymorphism was related to activation of reward-related brain regions during the reward task (Richter et al., 2017). ...
... Although dopamine genes appear to be most consistently related to activation of the striatum in reward tasks, some fMRI studies have found associations between candidate genes involved in dopamine function and activation of other PVS-related brain regions. For example, the DRD2 A1 allele has been associated with reduced activation of OFC and amygdala to rewards (Cohen et al., 2005;Felsted et al., 2010). Further, the Val allele of COMT has been linked to greater relative activation of mPFC to large unexpected rewards compared to losses (Camara et al., 2010). ...
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Reduced activation of positive valence systems (PVS), including blunted neural and physiological responses to pleasant stimuli and rewards, has been shown to prospectively predict the development of psychopathology. Yet, little is known about how reduced PVS activation emerges across development or what implications it has for prevention. We review genetic, temperament, parenting, and naturalistic and laboratory stress research on neural measures of PVS and outline developmentally-informed models of trajectories of PVS activation. PVS function is partly heritable and appears to reflect individual differences in early-emerging temperament traits. Although lab-induced stressors blunt PVS activation, effects of parenting and naturalistic stress on PVS are mixed and depend on the type of stress, developmental timing, and interactions amongst risk factors. We propose that there may be multiple, dynamic developmental trajectories to reduced PVS activation in which combinations of genes, temperament, and exposure to severe, prolonged, or uncontrollable stress may exert direct and interactive effects on PVS function. Critically, these risk factors may alter PVS development trajectories and/or PVS sensitivity to proximal stressors. Distinct factors may converge such that PVS activation proceeds along a typical, accelerated, chronically low, or stress-reactive trajectory. Finally, we present directions for future research with translational implications.
... FMRI and behavioral studies support an undermining effect of extrinsic rewards on motivation if the level of interest and intrinsic motivation are already high (Deci et al., 1999;Murayama and Kuhbandner, 2011;Murayama et al., 2010). Future aging research could investigate whether individual characteristics such as personality traits (Cohen et al., 2005;Jimura et al., 2010;Simon et al., 2010b), motivational orientation (i.e., to internal desires versus external compensation) (Linke et al., 2010), and dopamine functioning (Cohen et al., 2005) might optimize reward sensitivity and valuation. ...
... FMRI and behavioral studies support an undermining effect of extrinsic rewards on motivation if the level of interest and intrinsic motivation are already high (Deci et al., 1999;Murayama and Kuhbandner, 2011;Murayama et al., 2010). Future aging research could investigate whether individual characteristics such as personality traits (Cohen et al., 2005;Jimura et al., 2010;Simon et al., 2010b), motivational orientation (i.e., to internal desires versus external compensation) (Linke et al., 2010), and dopamine functioning (Cohen et al., 2005) might optimize reward sensitivity and valuation. ...
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The neural circuitry mediating the influence of motivation on long-term declarative or episodic memory formation is delineated in young adults, but its status is unknown in healthy aging. We examined the effect of reward and punishment anticipation on intentional declarative memory formation for words using an event-related functional magnetic resonance imaging (fMRI) monetary incentive encoding task in twenty-one younger and nineteen older adults. At 24-hour memory retrieval testing, younger adults were significantly more likely to remember words associated with motivational cues than neutral cues. Motivational enhancement of memory in younger adults occurred only for recollection ("remember" responses) and not for familiarity ("familiar" responses). Older adults had overall diminished memory and did not show memory gains in association with motivational cues. Memory encoding associated with monetary rewards or punishments activated motivational (substantia nigra/ventral tegmental area) and memory-related (hippocampus) brain regions in younger, but not older, adults during the target word periods. In contrast, older and younger adults showed similar activation of these brain regions during the anticipatory motivational cue interval. In a separate monetary incentive delay task that did not require learning, we found evidence for relatively preserved striatal reward anticipation in older adults. This supports a potential dissociation between incidental and intentional motivational processes in healthy aging. The finding that motivation to obtain rewards and avoid punishments had reduced behavioral and neural influence on intentional episodic memory formation in older compared to younger adults is relevant to life-span theories of cognitive aging including the dopaminergic vulnerability hypothesis.
... Due to neurobiological adaptations of long-term substance use, the engagement in healthy activities may be affected in AUD patients, characterized by a decreased sensitivity to natural reward and increased sensitivity to compulsive alcohol and drug-seeking behavior (Spanagel and Weiss, 1999;Cohen et al., 2005). A characteristic of such a dysfunctional reward system is the systematic discounting of delayed non-substance-related rewards (Kirby et al., 1999;Bickel and Marsch, 2001;Schmaal et al., 2012), which is considered to be one of the behavioral decision-making deficits (Monterosso et al., 2001). ...
... A possible influence of withdrawal symptoms on the measurement of anhedonia in the current study cannot be excluded since it has been substantiated that a possible decrease of dopaminergic state due to long-term substance use has to be taken into account while using the findings regarding reward sensitivity within the clinical practice (Robinson and Berridge, 1993;Volkow et al., 1996Volkow et al., , 2011. Moreover, this study positioned the delay discounting as a consequence of long-term substance use (Spanagel and Weiss, 1999;Cohen et al., 2005). However, it should be noted that delay discounting may act as a risk factor for substance use and may predict the likelihood to recover from substance use as well (Robles et al., 2011). ...
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Aim: Reward sensitivity affects individuals' motivation to engage in goal-directed behavior. Other concepts, critical for reward appraisal, that potentially influence activity participation encompass delay discounting and anhedonia. The aim of this study was to test the hypothesis that anhedonia and delay discounting influence the relationship between reward sensitivity and activity engagement. Methods: In total, 37 inpatient patients with an alcohol use disorder (AUD) and 37 matched healthy controls completed the behavioral activation system scale (BAS scale), the Pleasant Activities List (PAL), the Snaith-Hamilton Pleasure Scale (SHAPS) and the Delay Discounting Task (DDT). Results: Patients differed from controls on SHAPS, DDT-k, PAL substance-related activities (SRA), but not BAS and PAL non-substance-related activities (non-SRA). Correlational analyses revealed a strong correlation between BAS and PAL non-SRA in both patients (r = 0.53) and controls (r = 0.47), but also with PAL-SRA in patients (r = 0.40), although not controls (r = 0.09). BAS was negatively correlated with SHAPS in both groups and with DDT in controls. SHAPS was negatively linked to PAL non-SRA in both groups. The BAS-PAL non-SRA relationship was influenced by discount rates in controls. Conclusion: A strong link exists between reward sensitivity and engagement in non-SRA in both groups. Delay discounting affects the reward sensitivity and non-SRA association in healthy controls, while anhedonia did not impact the association between reward sensitivity and engagement in (non-)SRA in both conditions.
... Research has shown that individuals who are high in trait positive affect have a stronger Behavioral Activation System (BAS; Gray, 1987;Watson, Wiese, Vaidya, & Tellegen, 1999). The BAS system creates dopaminergic pathways to the brain in response to signals of reward (Cohen, Young, Baek, Kessler, & Ranganath, 2005). The feelings accompanying BAS activation include positive emotional reactions such as happiness. ...
... Variations in trait positive affect are linked to the Behavioral Activation System (BAS), which regulates appetitive motivation and facilitates the direction of approach behavior toward desired goals (e.g., Depue & Collins, 1999;Depue & Morrone-Strupinsky, 2005;Gray, 1987). Specifically, the BAS creates dopaminergic pathways to the brain in response to signals of reward (Cohen et al., 2005), and directs individuals toward situations and experiences that potentially yield reward. The basic function of the BAS is to ensure that individuals obtain resources that are essential to them (Watson et al., 1999). ...
Article
Employees may react differently to the perceived availability of motivating job characteristics during work activities, depending on the degree to which such motivating job characteristics are also present at the job level and individual differences. This study expands Job Characteristics Theory (JCT) by using a multilevel approach to predict how variations in motivating job characteristics relate to employee happiness during daily work activities. Based on adaptation level theory and the affective-reactivity hypothesis, we predicted that the positive relationship between perceived motivating job characteristics and happiness during work activities is moderated by motivating job characteristics at the job level and individual differences in trait positive affect. A sample of 68 employees filled out a general survey and reported on their job characteristics and happiness during 741 work activities using a day reconstruction method across five working days. In line with adaptation level theory, multilevel results confirmed that the perceived availability of motivating job characteristics during work activities relates positively to happiness during that same work activity, but only when similar motivating job characteristics at the job level are low. In addition, trait positive affect further moderated this cross-level interaction. In line with the affective-reactivity hypothesis, the 3-way interaction effect showed that for employees who are high in positive affect, the perceived availability of motivating job characteristics related positively to happiness during specific work activities, regardless of whether similar motivating job characteristics at the job level were high or low. We discuss how these findings add important temporal dynamics to JCT.
... Recent studies indicate that specific personality traits, in particular neuroticism and extraversion, are associated with social behavior 31 . While personality traits and tVNS-associated cognitive effects are undoubtedly influenced by multiple neurotransmitter systems, specifically extraversion and neuroticism have been linked to dopamine-dependent reward-processing [e.g., 32,33 ]. Thereby, a highly reactive dopaminergic system, e.g., as measured by dopamine-relevant genes, structural volume of dopamine-rich brain regions or dopamine receptor availability, has been associated with high extraversion, whereas the opposite has been suggested for neuroticism. ...
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The vagus nerve constitutes a key link between the autonomic and the central nervous system. Previous studies provide evidence for the impact of vagal activity on distinct cognitive processes including functions related to social cognition. Recent studies in animals and humans show that vagus nerve stimulation is associated with enhanced reward-seeking and dopamine-release in the brain. Social interaction recruits similar brain circuits to reward processing. We hypothesize that vagus nerve stimulation (VNS) boosts rewarding aspects of social behavior and compare the impact of transcutaneous VNS (tVNS) and sham stimulation on social interaction in 19 epilepsy patients in a double-blind pseudo-randomized study with cross-over design. Using a well-established paradigm, i.e., the prisoner’s dilemma, we investigate effects of stimulation on cooperative behavior, as well as interactions of stimulation effects with patient characteristics. A repeated-measures ANOVA and a linear mixed-effects model provide converging evidence that tVNS boosts cooperation. Post-hoc correlations reveal that this effect varies as a function of neuroticism, a personality trait linked to the dopaminergic system. Behavioral modeling indicates that tVNS induces a behavioral starting bias towards cooperation, which is independent of the decision process. This study provides evidence for the causal influence of vagus nerve activity on social interaction.
... Similarly, on catechol-O-methyltransferase (COMT), a gene involved in the breakdown of catecholamines such as dopamine, the presence of the T allele was associated with higher levels of boredom and lower levels of self-control ( Fig. 3.2). The strong association between dopamine and reward processing (Cohen et al. 2005) may suggest that highly boredom prone individuals present with dysfunctional regulation of dopamine, a hypothesis clearly warranting further research. . Note: a Virtual foraging task: people swiped a touch screen tapping on berries to collect them. ...
Chapter
From the second half of the twentieth century to the end, the blossoming interest of the Mental health professionals on the phenomenon of boredom increased to unimagined levels. Particularly, the psychoanalysts riddled the journals’ pages with titles such as those by well-known psychoanalyst Martin Wangh “Boredom in psychoanalytic perspective” (1975), and “Some psychoanalytic observation on boredom” (1979). However, many psychoanalysts were heirs of the father of Psychoanalysis, Sigmund Freud. This was also the case of the French psychiatrist and psychoanalyst Jacques Lacan. The present chapter aims to develop the notion of boredom and its relationship with psychoanalysis by taking into account many of its roots in the past century. Particularly, we consider boredom is a symptom of other conditions. Therefore, to work on this concept from a psychoanalytical perspective, we will mainly follow parts of Lacan and Freud’s works, who tackled the complex question, and some clinical vignettes.
... Overall, these studies suggest that decreased WM organization across regions and hemispheres is associated with behavioral characteristics that encompass both broad factors and narrower facets of extraversion. In accordance, extraverts typically show high functional connectivity within brain networks subserving reward and motivation in response to rewarding stimuli (Canli, 2004;Cohen, Young, Baek, Kessler, & Ranganath, 2005;Deckersbach et al., 2006). Similar findings have been reported in resting-state connectivity studies (Adelstein et al., 2011;Aghajani et al., 2014;Pang et al., 2016). ...
Article
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The trait of extraversion is one of the longest-standing domains that captures the social dimension of personality and can potentially explain the covariation of a wide variety of behaviors. To date, there is a growing recognition that human behavior should be specified not only through the psychological mechanisms underlying each trait but also through their underlying neurobehavioral systems. While imaging studies have revealed important initial insights into the structural and functional neural correlates of extraversion, current knowledge about the relationships between extraversion and brain structures is still rather limited, especially with regard to the relationship between extraversion and white matter (WM). In this study, we aimed to investigate WM microstructure in extraversion in greater depth. Thirty-five healthy volunteers (21 women; mean age 35) underwent magnetic resonance imaging, as a part of a larger project aimed at investigating the longitudinal effect of motor training. WM integrity was assessed using the diffusion tensor imaging technique combining multiple diffusion tensor measures. Extraversion was assessed by the Eysenck Personality Questionnaire-Revised. Voxelwise correlation analyses between fractional anisotropy, axial diffusivities, and radial diffusivities maps and extraversion score showed decreased connectivity in the right inferior fronto-occipital fasciculus and forceps major among individuals who had high extraversion ratings. In conclusion, individual differences in extraversion may reflect differential organization of the WM tracts connecting frontal cortex, temporal, and occipital areas, which are related to socioemotional and control functions.
... Numerous studies in healthy adults found that individual differences in trait personality measures of positive and negative emotionality (extraversion and neuroticism, respectively; Costa and McCrae 1980) are associated with brain activations during various tasks, but critically, these traits were not significantly associated with behavior. Extraversion and neuroticism did not predict high-versus low-risk gambling (Cohen et al. 2005), inhibitory control (Rodrigo et al. 2015), response conflict (Yücel et al. 2007), or WM performance (Kumari et al. 2004;Gray et al. 2005). However, these factors may associate with behavior when the task itself includes emotional stimuli: extraversion correlated with emotional Stroop reaction time (Haas et al. 2006). ...
Article
Addiction is characterized by an erosion of cognitive control toward drug taking that is accentuated by negative emotional states. Here we tested the hypothesis that enhanced interference on cognitive control reflects a loss of segregation between cognition and emotion in addiction. We analyzed Human Connectome Project data from 1206 young adults, including 89 with cannabis dependence (CD). Two composite factors, one for cognition and one for emotion, were derived using principal component (PC) analyses. Component scores for these PCs were significantly associated in the CD group, such that negative emotionality correlated with poor cognition. However, the corresponding component scores were uncorrelated in matched controls and nondependent recreational cannabis users (n = 87). In CD, but not controls or recreational users, functional magnetic resonance imaging activations to emotional stimuli (angry/fearful faces > shapes) correlated with activations to cognitive demand (working memory; 2-back > 0-back). Canonical correlation analyses linked individual differences in cognitive and emotional component scores with brain activations. In CD, there was substantial overlap between cognitive and emotional brain-behavior associations, but in controls, associations were more restricted to the cognitive domain. These findings support our hypothesis of impaired segregation between cognitive and emotional processes in CD that might contribute to poor cognitive control under conditions of increased emotional demand.
... Specifically, in healthy male adults, extraversion was negatively associated with the GMV of the right caudate nucleus (Forsman et al., 2012), while in studies of healthy adults with a growing number of women, this negative correlation was diminished and even changed to the inverse relationship (Cremers et al., 2011). The caudate is well known to be involved in reward-related processing (Cohen, Young, Baek, Kessler, & Ranganath, 2005;Delgado, Miller, Inati, & Phelps, 2005). Neuroimaging studies have indicated that extraverts who are known to be reward motivated may recruit the reward-sensitive regions more strongly during tasks that most likely trigger rewarding experiences (Canli et al., 2001). ...
Article
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Extraversion is a fundamental personality dimension closely related to an individual's life outcomes and mental health. Although an increasing number of studies have attempted to identify the neurostructural markers of extraversion, the results have been highly inconsistent. The current study aimed to achieve a comprehensive understanding of brain gray matter (GM) correlates of extraversion with a systematic review and meta-analysis approach. Our review showed relatively high interstudy heterogeneity among previous findings. Our meta-analysis of whole-brain voxel-based morphometry studies revealed that extraversion was stably associated with six core brain regions. Additionally, meta-regression analyses identified brain regions where the associations of extraversion with GM volume were modulated by gender and age. The relationships between extraversion and GM structures were discussed based on three extraversion-related functional systems. Furthermore, we explained the gender and age effects. Overall, our study is the first to reveal a comprehensive picture of brain GM correlates of extraversion, and the findings may be useful for the selection of targeted brain areas for extraversion interventions. K E Y W O R D S extraversion, meta-analysis, structural magnetic resonance imaging, systematic review, voxel-based morphometry
... Specifically, in healthy male adults, extraversion was negatively associated with the GMV of the right caudate nucleus (Forsman et al., 2012), while in studies of healthy adults with a growing number of women, this negative correlation was diminished and even changed to the inverse relationship (Cremers et al., 2011). The caudate is well known to be involved in reward-related processing (Cohen, Young, Baek, Kessler, & Ranganath, 2005;Delgado, Miller, Inati, & Phelps, 2005). Neuroimaging studies have indicated that extraverts who are known to be reward motivated may recruit the reward-sensitive regions more strongly during tasks that most likely trigger rewarding experiences (Canli et al., 2001). ...
Article
Extraversion is a fundamental personality dimension closely related to an individual's life outcomes and mental health. Although an increasing number of studies have attempted to identify the neurostructural markers of extraversion, the results have been highly inconsistent. The current study aimed to achieve a comprehensive understanding of brain gray matter (GM) correlates of extraversion with a systematic review and meta‐analysis approach. Our review showed relatively high interstudy heterogeneity among previous findings. Our meta‐analysis of whole‐brain voxel‐based morphometry studies revealed that extraversion was stably associated with six core brain regions. Additionally, meta‐regression analyses identified brain regions where the associations of extraversion with GM volume were modulated by gender and age. The relationships between extraversion and GM structures were discussed based on three extraversion‐related functional systems. Furthermore, we explained the gender and age effects. Overall, our study is the first to reveal a comprehensive picture of brain GM correlates of extraversion, and the findings may be useful for the selection of targeted brain areas for extraversion interventions.
... The relation between Extraversion, social interactions and positive affect has always been the focus of the temperamental versus instrumental discussion. Whereas temperamental explanations argue that extraverts are happier simply because they are more extravertedcausing them to react more positively to stimuli (Cohen, Young, Baek, Kessler, & Ranganath, 2005;DeYoung, Hawes, Civai, & Rustichini, 2014) or have a higher setpoint for happiness (Gross et al., 1998) -, instrumental explanations mostly involve social interactions either mediating or moderating this relation (e.g., Howell, 2005). Thus, there are four possibilities to discuss: (1) The temperamental explanation would suggest that trait Extraversion predicts affect regardless of extraverted states or situations (Costa & McCrae, 1980;Howell, 2005). ...
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Personality traits are strongly related to subjective well-being, but the mechanisms that account for this association mostly remain unclear. Over the years, several theories of this relation have been proposed and tested, but none of these could provide a satisfactory answer. We propose and test a new model of the personality–affect relation that integrates the dynamic mediation hypothesis and the social participation hypothesis. Our model proposes that personality traits are related to affect because they are associated with specific daily behaviors and situations that in turn promote positive affect. We present data from an experience sampling study (N = 206; observations = 4381) that indicate that (a) personality traits are associated with average levels of enacted personality states and experienced situation characteristics, (b) personality states and situation characteristics are associated with affective states, (c) affective states are associated with trait affect, and (d) that these mechanisms mediate the relations between personality traits and trait affect. These results support our model and call for a closer integration of research in personality and social psychology.
... All of these three variables are associated with creativity (Agnoli et al., 2016;De Fruyt et al., 2000;Hao et al., 2016;Perkins et al., 2015;Singh and Kaushik, 2015a). In particular, links to the dopaminergic system have been repeatedly described for extraversion (Cohen et al., 2005;Depue and Collins, 1999a;Golimbet et al., 2007;Lhommée et al., 2017;Rammsayer, 1998;Wacker et al., 2006) and neuroticism (emotional stability) (Barbato et al., 2012;Canli, 2008;Fischer et al., 1997;Tochigi et al., 2006). There is also some evidence for a relationship between fluency and dopamine (Murphy et al., 2013). ...
Article
Creativity is a sine qua non ability for almost all aspects of everyday life. Although very profound behavioural models were provided by 21st century psychologists, the neural correlates of these personality features associated with creativity are largely unknown. Recent models suggest strong relationships between dopamine release and various creative skills. Herein, we employed functional connectivity analyses of resting-state functional magnetic imaging data in order to shed light on these neural underpinnings of creative aspects. For improved sensitivity, we performed the study at ultra-high magnetic field (7 T). Seed regions were defined based on subcortical (ventral tegmental area/substantia nigra, nucleus caudatus) activation foci of a remote associates task (RAT). In addition, bilateral PCC was used as seed region to examine the default-mode network. Network strength across subjects was regressed against a battery of psychological variables related to creativity. Dopaminergic network variations turned out to be indicative for individual differences in creative traits. In this regard, the caudate network showed stronger connectivity in individuals with higher extraversion measures, while connectivity with the midbrain network was found increased with higher ideational behaviour and emotional stability.
... Была показана также [4,5] ассоциация минорного аллеля rs1800497 с развитием аддиктивных расстройств, нарушения мотивации при которых являются ключевым симптомом. При изучении лиц из общей популяции с использованием экспериментальных парадигм с вознаграждением обнаружено [6][7][8][9][10] влияние полиморфизма rs1800497 на активацию мозга во время ожидания награды, в частности вкусной пищи. В нескольких исследованиях здоровых [11][12][13] лиц влияние DRD2 на показатели мотивации определяли с помощью психометрических инструментов. ...
Article
Aim: To evaluate the association of the DRD2 gene and DRD2 x HTR2C interaction with hedonic and activational aspects of approach motivation in schizophrenia. Material and methods: Genotypes at polymorphic loci DRD2 rs1800497 and HTR2C rs6318 (Cys23Ser) were identified in a sample that included 174 patients with schizophrenic spectrum disorders and 268 healthy subjects without a family history of psychoses. The participants completed the BIS/BAS and Temporal Experience of Pleasure Scale (TEPS). Results and conclusion: A MANCOVA with sex and age as covariates revealed the effect of the 'DRD2 x HTR2C x diagnosis' interaction on the BAS scores (p=0.033). The effect was significant for the Fun-Seeking and Drive scales. Among patients, the carriers of the DRD2 TT/CT x HTR2C GG/G genotype showed the highest scores on the both scales, and those with the minor alleles in the two loci had the lowest ones. Differences between these groups were nominally significant for both the Fun-Seeking and Drive, but did not survive the correction for multiple comparisons. Among controls, subjects without minor alleles demonstrated the highest scores on these two scales. They differed significantly from the carriers of the DRD2 TT/CT+HTR2C GG/G genotype on the Fun-Seeking (p=0.008). No effects of DRD2 and HTR2C on TEPS scores were found. In general, the results of the study can be interpreted in favor of the hypothesis about the role of the HTR2C and DRD2 genes interaction in the variability of the activational aspects of approach motivation in schizophrenia and healthy subjects. However, the lack of differences survived correction for multiple comparisons makes it difficult to interpret the revealed effects.
... Any variation in adopted regulatory mode in humans likely depends on many genes and their interactions, with one's preference for assessment or locomotion not solely driven by variation in PRKG1. Genes known to regulate dopamine, a neurotransmitter involved in calculating value and reward signals in the brain, represent another likely target, among many, for exploring the genetic contributions to self-regulation (34). We used a composite measure of regulatory mode preference, one commonly used in the literature (35), to explore differences in behavior and genotype. ...
Article
Foraging is a goal-directed behavior that balances the need to explore the environment for resources with the need to exploit those resources. In Drosophila melanogaster , distinct phenotypes have been observed in relation to the foraging gene ( for ), labeled the rover and sitter. Adult rovers explore their environs more extensively than do adult sitters. We explored whether this distinction would be conserved in humans. We made use of a distinction from regulatory mode theory between those who “get on with it,” so-called locomotors, and those who prefer to ensure they “do the right thing,” so-called assessors. In this logic, rovers and locomotors share similarities in goal pursuit, as do sitters and assessors. We showed that genetic variation in PRKG1 , the human ortholog of for , is associated with preferential adoption of a specific regulatory mode. Next, participants performed a foraging task to see whether genetic differences associated with distinct regulatory modes would be associated with distinct goal pursuit patterns. Assessors tended to hug the boundary of the foraging environment, much like behaviors seen in Drosophila adult sitters. In a patchy foraging environment, assessors adopted more cautious search strategies maximizing exploitation. These results show that distinct patterns of goal pursuit are associated with particular genotypes of PRKG1 , the human ortholog of for .
... Specifically, introverts tend to adopt a rational thinking style (e.g., "I enjoy intellectual challenges"), while extraversion is more associated with an experiential thinking style (e.g., "I like to rely on my intuitive impressions") and a dependence on habitual over goal-directed learning mechanisms (Pacini and Epstein, 1999;Skatova et al., 2013). A related literature suggests that extraverts are more reward-sensitive (Smillie, 2013), as evidenced by neuroimaging studies of gambling behavior (Cohen et al., 2005). ...
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Philosophers have long debated whether, if determinism is true, we should hold people morally responsible for their actions since in a deterministic universe, people are arguably not the ultimate source of their actions nor could they have done otherwise if initial conditions and the laws of nature are held fixed. To reveal how non-philosophers ordinarily reason about the conditions for free will, we conducted a cross-cultural and cross-linguistic survey (N = 5,268) spanning twenty countries and sixteen languages. Overall, participants tended to ascribe moral responsibility whether the perpetrator lacked sourcehood or alternate possibilities. However, for American, European, and Middle Eastern participants, being the ultimate source of one’s actions promoted perceptions of free will and control as well as ascriptions of blame and punishment. By contrast, being the source of one’s actions was not particularly salient to Asian participants. Finally, across cultures, participants exhibiting greater cognitive reflection were more likely to view free will as incompatible with causal determinism. We discuss these findings in light of documented cultural differences in the tendency toward dispositional versus situational attributions.
... The common paradigm entails the recording of neural activity in response to a stimulus and the assessment of the extent to which the strength of the neural response depends on individual trait levels. The involved stimuli can range from the simple passive viewing of emotional faces (e.g., Canli et al., 2001;Reuter et al., 2004) to complex naturalistic scenarios with actual behavioral relevance for the participants (e.g., Mobbs et al., 2007), and various personality traits such as neuroticism (Haas, Omura, Constable, & Canli, 2007), extraversion (Cohen, Young, Baek, Kessler, & Ranganath, 2005), or self-transcendence (Montag, Reuter, & Axmacher, 2011) have been examined. This research strategy has led to a substantial body of research on the neural correlates of individual differences. ...
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Personality and individual differences originate from the brain. Despite major advances in the affective and cognitive neurosciences, however, it is still not well understood how personality and single personality traits are represented within the brain. Most research on brain-personality correlates has focused either on morphological aspects of the brain such as increases or decreases in local gray matter volume, or has investigated how personality traits can account for individual differences in activation differences in various tasks. Here, we propose that personality neuroscience can be advanced by adding a network perspective on brain structure and function, an endeavor that we label personality network neuroscience. With the rise of resting-state functional magnetic resonance imaging (MRI), the establishment of connectomics as a theoretical framework for structural and functional connectivity modeling, and recent advancements in the application of mathematical graph theory to brain connectivity data, several new tools and techniques are readily available to be applied in personality neuroscience. The present contribution introduces these concepts, reviews recent progress in their application to the study of individual differences, and explores their potential to advance our understanding of the neural implementation of personality. Trait theorists have long argued that personality traits are biophysical entities that are not mere abstractions of and metaphors for human behavior. Traits are thought to actually exist in the brain, presumably in the form of conceptual nervous systems. A conceptual nervous system refers to the attempt to describe parts of the central nervous system in functional terms with relevance to psychology and behavior. We contend that personality network neuroscience can characterize these conceptual nervous systems on a functional and anatomical level and has the potential do link dispositional neural correlates to actual behavior.
... To ensure that effects were not accounted for by stable personality traits linked to hypersensitivity to reward or alcohol misuse, we controlled for impulsivity, which has been linked to VS rewardrelated reactivity and alcohol use (Beck et al., 2009), and extraversion, which predicts brain reward-related functioning (Cohen et al., 2005) and alcohol use (Kuntsche et al., 2006). Impulsivity was assessed at age 20 via self-report using the Barratt Impulsiveness Scale-Version II, a 30 item measure tapping several aspects of impulsivity, including deficits in behavioral control (Patton and Stanford, 1995) (α = 0.79) Extraversion was assessed age 20 via self-report on the 12-item extraversion subscale of the NEO Personality Inventory-Revised (NEO PI-R Short Form) (α = 0.64) (Costa and McCrae, 1997). ...
Article
Background: Alcohol use is commonly initiated during adolescence, with earlier onset known to increase the risk for alcohol use disorder (AUD). Altered function in neural reward circuitry is thought to increase the risk for AUD. To test the hypothesis that adolescent alcohol misuse primes the brain for alcohol-related psychopathology in early adulthood, we examined whether adolescent alcohol consumption rates predicted reward responsivity in the ventral striatum (VS), and in turn, AUD symptoms in adulthood. Methods: A total of 139 low income, racially diverse urban males reported on their alcohol use at ages 11, 12, 15, and 17; completed self-reports of personality, psychiatric interviews, and a functional magnetic resonance imaging (fMRI) scan at age 20; and completed a psychiatric interview at age 22. We measured adolescent alcohol use trajectories using latent growth curve modeling and measured neural responses to monetary reward using a VS region of interest. We tested indirect effects of adolescent alcohol use on AUD symptoms at age 22 via VS reward-related reactivity at age 20. Results: Greater acceleration in adolescent alcohol use predicted increased VS response during reward anticipation at age 20. VS reactivity to reward anticipation at age 20 predicted AUD symptoms at age 22, over and above concurrent symptoms. Accelerated adolescent alcohol use predicted AUD symptoms in early adulthood via greater VS reactivity to reward anticipation. Conclusions: Prospective findings support a pathway through which adolescent alcohol use increases the risk for AUD in early adulthood by impacting reward-related neural functioning. These results highlight increased VS reward-related reactivity as a biomarker for AUD vulnerability.
... Few studies have examined associations between broad personality traits (and their facets) and neural correlates of reward sensitivity, though preliminary evidence suggests a positive association between extraversion and reward sensitivity. For example, fMRI studies of adolescents and adults have found that greater extraversion was associated with increased activation in the ventral striatum and medial orbital frontal cortex following the receipt of reward (Cohen, Young, Baek, Kessler, & Ranganath, 2005;Forbes et al., 2010;Kennis et al., 2013;Simon et al., 2010). Conversely, greater behavioral inhibition (i.e. ...
Article
Affective personality traits, such as extraversion and neuroticism, are associated with individual differences in reward system functioning. The reward positivity (ΔRewP) is an event-related potential (ERP) component that indexes sensitivity to reward, and can be elicited by feedback indicating monetary gains relative to losses. In a sample of 508 adolescent girls, the current study examined the relationship between extraversion, neuroticism, and their respective facets and the ΔRewP. Results indicated an Extraversion × Neuroticism interaction, such that greater extraversion was associated with an increased ΔRewP, but only in the context of low neuroticism. This association was primarily due to the extraversion facet positive emotionality-high levels of positive emotionality were associated with an increased ΔRewP, but only in the context of low neuroticism. In addition, increased neuroticism diminished the age-related increase in the ΔRewP. The current study suggests that both extraversion and neuroticism are associated with reward system function in adolescence.
... A variety of biological and environmental factors may impact individual differences in neurobiological responses during decision making involving risk and reward. For example, genetic variants thought to influence dopamine signaling have been linked to brain activation during decision making [42] and in response to reward processing [43,44]. Epigenetic factors may also contribute to individual differences in risk/reward processing, as a recent study showed that DNA methylation of the promoter for the dopamine transporter gene was associated with nucleus accumbens activation during loss anticipation [45]. ...
Article
Beginning to engage in heavy alcohol use during adolescence, as opposed to later in life, is associated with elevated risk for a variety of negative consequences, including the development of an alcohol use disorder. Behavioral studies suggest that poor decision making predicts alcohol use during adolescence; however, more research is needed to determine the neurobiological risk factors that underlie this association. Using functional magnetic resonance imaging, brain activation during decision making involving risk and reward was assessed in 47 adolescents (14-15 years old) with no significant history or alcohol or drug use. After baseline assessment, participants completed follow-up interviews every 3 months to assess the duration to onset of binge drinking. Adolescents who made a greater number of risky selections and had greater activation in the nucleus accumbens, precuneus, and occipital cortex during decision making involving greater potential for risk and reward began binge drinking sooner. Findings suggest that heightened activation of reward circuitry during decision making under risk is a neurobiological risk factor for earlier onset of binge drinking. Furthermore, brain activation was a significant predictor of onset to binge drinking, even after controlling for decision-making behavior, suggesting that neurobiological markers may provide additional predictive validity over behavioral assessments. Interventions designed to modify these behavioral and neurobiological risk factors may be useful for curbing heavy alcohol use during adolescence.
... Such experiments seek to identify brain regions that respond to trait-relevant stimulation and then assess, whether the regions react differently in participants with varying trait levels. Over a range of different experimental set-ups and different personality assessment methods, this line of research has repeatedly confirmed that personality modulates how the brain responds to affective and cognitive stimulation (Canli et al., 2001;Cohen et al., 2005;Most et al., 2006;Reuter et al., 2004;Haas et al., 2007;Saggar et al., 2016). ...
Article
A prevailing topic in personality neuroscience is the question how personality traits are reflected in the brain. Functional and structural networks have been examined by functional and structural magnetic resonance imaging, however, the structural correlates of functionally defined networks have not been investigated in a personality context. By using the Temperament and Character Inventory (TCI) and Diffusion Tensor Imaging (DTI), the present study assesses in a sample of 116 healthy participants how personality traits proposed in the framework of the biopsychosocial theory on personality relate to white matter pathways delineated by functional network imaging. We show that the character trait self-directedness relates to the overall microstructural integrity of white matter tracts constituting the salience network as indicated by DTI-derived measures. Self-directedness has been proposed as the executive control component of personality and describes the tendency to stay focused on the attainment of long-term goals. The present finding corroborates the view of the salience network as an executive control network that serves maintenance of rules and task-sets to guide ongoing behavior.
... Further, we selected the promoter rs12364283 SNP of the D2 dopamine receptor (DRD2) genethe C allele has been shown to confer higher transcriptional activity (Zhang et al., 2007) − because of the association D2 has with reward signaling (Suhara and Miyoshi, 2007;Assadi et al., 2009), reinforcement learning (Frank and Hutchison, 2009;Baker et al., 2013), and addiction (Noble, 1994(Noble, , 2000. Likewise, the Taq1A polymorphism (rs 1800497) of the ANKK1 gene was also selected because of its association with striatal D2 receptor function (Thompson et al., 1997) but see Laruelle et al. (1998), altered activation of OFC (Cohen et al., 2005), and VS (Nymberg et al., 2014), impaired reinforcement learning (Klein et al., 2007), and addiction Noble, 1998Noble, , 2000Noble, , 2003Abi-Dargham, 2004;Munafo et al., 2007). ...
Article
Background Abnormalities in reward circuit function are considered a core feature of addiction. Yet, it is still largely unknown whether these abnormalities stem from chronic drug use, a genetic predisposition, or both. Methods In the present study, we investigated this issue using a large sample of adolescent children by applying structural equation modeling to examine the effects of several dopaminergic polymorphisms of the D1 and D2 receptor type on the reward function of the ventral striatum (VS) and orbital frontal cortex (OFC), and whether this relationship predicted the propensity to engage in early alcohol misuse behaviors at 14 years of age and again at 16 years of age. Results The results demonstrated a regional specificity with which the functional polymorphism rs686 of the D1 dopamine receptor (DRD1) gene and Taq1A of the ANKK1 gene influenced medial and lateral OFC activation during reward anticipation, respectively. Importantly, our path model revealed a significant indirect relationship between the rs686 of the DRD1 gene and early onset of alcohol misuse through a medial OFC × VS interaction. Conclusions These findings highlight the role of D1 and D2 in adjusting reward-related activations within the mesocorticolimbic circuitry, as well as in the susceptibility to early onset of alcohol misuse.
... Esto parece recoger parte de la evidencia obtenida en otros estudios, en los cuales se ha encontrado una alta relación entre la vulnerabilidad a una mayor SaR y el abuso de alcohol o a la alimentación disfuncional (Loxton y Dawe, 2001). Esto se ha relacionado a nivel neurofisiológico por la regulación de la dopamina, y la influencia de la activación del cerebro en regiones más sensibles ante la recompensa (Cohen et al., 2005). La similitud entre obesidad y drogadicción también ha sido discutida por Wang et al. (2004), de modo que la literatura establece tal relación con bastantes fundamentos. ...
Article
Full-text available
This paper presents the results of a cross-sectional research that analyzed the relationship between risky dietary behaviors and academic achievement in university students. A survey was applied to students from the University Católica del Norte (Coquimbo-Chile), and measurements were made of their body mass index. The results of the study suggest that students with higher vulnerability to sensitivity to the reward presented higher levels of overeating, or tendency to binge eating. In addition, these students had higher levels of preferences for fatty and sweet foods. These constructs proved to be determinants of a higher body mass index, and a lower academic performance. The results of the study suggest that strategies to promote healthy eating in college students with vulnerability to reward sensitivity, must be more effective in improving overall academic performance.
... It has also been noted that individuals differ in the degree of neural activation to anticipation of non-drug rewards. For example, individuals with high-reward sensitivity, as measured by self-report personality measures, show increased neural activation in brain reward circuitry, particularly in the VS and the orbitofrontal cortex (OFC), during non-drug reward anticipation compared to individuals with low-reward sensitivity [22,23]. This individual variability in brain reward function may influence drug use via drug craving, biasing toward drug cues, and motivation to seek the drug [24,25]. ...
Article
Full-text available
One known risk factor for drug use and abuse is sensitivity to rewarding effects of drugs. It is not known whether this risk factor extends to sensitivity to non-drug rewards. In this study with healthy young adults, we examined the association between sensitivity to the subjective rewarding effects of amphetamine and a neural indicator of anticipation of monetary reward. We hypothesized that greater euphorigenic response to amphetamine would be associated with greater neural activation to anticipation of monetary reward (Win > Loss). Healthy participants (N = 61) completed four laboratory sessions in which they received d-amphetamine (20 mg) and placebo in alternating order, providing self-report measures of euphoria and stimulation at regular intervals. At a separate visit 1–3 weeks later, participants completed the guessing reward task (GRT) during fMRI in a drug-free state. Participants reporting greater euphoria after amphetamine also exhibited greater neural activation during monetary reward anticipation in mesolimbic reward regions, including the bilateral caudate and putamen. This is the first study to show a relationship between neural correlates of monetary reward and sensitivity to the subjective rewarding effects of amphetamine in humans. These findings support growing evidence that sensitivity to reward in general is a risk factor for drug use and abuse, and suggest that sensitivity of drug-induced euphoria may reflect a general sensitivity to rewards. This may be an index of vulnerability for drug use or abuse.
... Similarly, on catechol-O-methyltransferase (COMT), a gene involved in the breakdown of catecholamines such as dopamine, the presence of the T allele was associated with higher levels of boredom and lower levels of self-control ( Fig. 3.2). The strong association between dopamine and reward processing (Cohen et al. 2005) may suggest that highly boredom prone individuals present with dysfunctional regulation of dopamine, a hypothesis clearly warranting further research. . Note: a Virtual foraging task: people swiped a touch screen tapping on berries to collect them. ...
Book
This book offers a unique perspective on the topic of boredom, with chapters written by diverse representatives of various mental health disciplines and philosophical approaches. On one hand, studying boredom involves the mental processes of attention, memory, perception, creativity, or language use; on the other, boredom can be understood by taking into account many pathological conditions such as depression, stress, and anxiety. This book seeks to fill the knowledge gap in research by discussing boredom through an interdisciplinary dialogue, giving a comprehensive overview of the past and current literature within boredom studies, while discussing the neural bases and causes of boredom and its potential consequences and implications for individual and social well-being. Chapters explore the many facets of boredom, including: • Understanding the cognitive-affective mechanisms underlying experiences of boredom • Philosophical perspectives on boredom, self-consciousness, and narrative • How boredom shapes both basic and complex human thoughts, feelings, and behavior • Analyzing boredom within Freudian and Lacanian frameworks Boredom Is in Your Mind: A Shared Psychological-Philosophical Approach is a pioneering work that brings together threads of cross-disciplinary boredom research into one comprehensive resource. It is relevant for graduate students and researchers in myriad intersecting disciplines, among them cognitive psychology, cognitive neurosciences, and clinical psychology, as well as philosophy, logic, religion, and other areas of the humanities and social sciences.
... Specifically, introverts tend to adopt a rational thinking style (e.g., "I enjoy intellectual challenges"), while extraversion is more associated with an experiential thinking style (e.g., "I like to rely on my intuitive impressions") and a dependence on habitual over goal-directed learning mechanisms (Pacini & Epstein, 1999;Skatova, Chan & Daw, 2013). A related literature suggests that extraverts are more reward-sensitive (Smillie, 2013), as evidenced by neuroimaging studies of gambling behavior (Cohen, Young, Baek, Kessler, & Ranganath, 2005). ...
Preprint
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Philosophers have long debated whether, if determinism is true, we should hold people morally responsible for their actions since in a deterministic universe, people are arguably not the ultimate source of their actions nor could they have done otherwise if initial conditions and the laws of nature are held fixed. To reveal how non-philosophers ordinarily reason about the conditions for free will, we conducted a cross-cultural and cross-linguistic survey (N = 5,268) spanning twenty countries and sixteen languages. Overall, participants tended to ascribe moral responsibility whether the perpetrator lacked sourcehood or alternate possibilities. However, for American, European, and Middle Eastern participants, being the ultimate source of one's actions promoted perceptions of free will and control as well as ascriptions of blame and punishment. By contrast, being the source of one's actions was not particularly salient to Asian participants. Finally, across cultures, participants exhibiting greater cognitive reflection were more likely to view free will as incompatible with causal determinism. We discuss these findings in light of documented cultural differences in the tendency toward dispositional versus situational attributions.
... There are several behavioral and neuroimaging studies linking candidate genes involved in the etiology of SZ with RL performance in HC participants [25,30,79,80]. In our study, we have shown that the DAT1/SLC6A3 rs28363170 polymorphism is associated with RL performance on PST among HC participants. ...
Article
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Schizophrenia spectrum disorders (SZ) are characterized by impairments in probabilistic reinforcement learning (RL), which is associated with dopaminergic circuitry encompassing the prefrontal cortex and basal ganglia. However, there are no studies examining dopaminergic genes with respect to probabilistic RL in SZ. Thus, the aim of our study was to examine the impact of dopaminergic genes on performance assessed by the Probabilistic Selection Task (PST) in patients with SZ in comparison to healthy control (HC) subjects. In our study, we included 138 SZ patients and 188 HC participants. Genetic analysis was performed with respect to the following genetic polymorphisms: rs4680 in COMT, rs907094 in DARP-32, rs2734839, rs936461, rs1800497, and rs6277 in DRD2, rs747302 and rs1800955 in DRD4 and rs28363170 and rs2975226 in DAT1 genes. The probabilistic RL task was completed by 59 SZ patients and 95 HC subjects. SZ patients performed significantly worse in acquiring reinforcement contingencies during the task in comparison to HCs. We found no significant association between genetic polymorphisms and RL among SZ patients; however, among HC participants with respect to the DAT1 rs28363170 polymorphism, individuals with 10-allele repeat genotypes performed better in comparison to 9-allele repeat carriers. The present study indicates the relevance of the DAT1 rs28363170 polymorphism in RL in HC participants.
... Reward system is considered to develop non-linearly (Ernst et al., 2005;Bjork et al., 2010;Blakemore and Robbins, 2012;Albert et al., 2013;Lamm et al., 2014;Luking, 2015;Ethridge et al., 2017;Kujawa et al., 2018). Adolescents show hypersensitivity to both social and non-social rewards (Martin et al., 2002;Bjork et al., 2004;Cohen et al., 2005;Ernst et al., 2005;Galvan et al., 2006;Casey et al., 2008;Steinberg, 2008;Geier and Luna, 2009;Forbes et al., 2010;Galvan, 2010;Geier et al., 2010;Simon et al., 2010;Van Leijenhorst et al., 2010;Wahlstrom et al., 2010;Spear, 2011;Nees et al., 2012;Urošević et al., 2012;Hoogendam et al., 2013;Kennis et al., 2013;Richards et al., 2013;Lamm et al., 2014;Weigard et al., 2014;Braams et al., 2015;Silverman et al., 2015;Foulkes and Blakemore, 2016;Shulman et al., 2016;Steinberg et al., 2017). Rewards can induce intense emotional experiences in adolescents (Ernst et al., 2006;Galvan et al., 2006;Crone and Dahl, 2012;Blakemore and Mills, 2014;Gilbert et al., 2019;, and their motivation toward rewards is an important part of socialization (Kohls et al., 2011;Jia et al., 2013). ...
Article
Full-text available
Adolescence is an essential developmental period characterized by reward-related processes. The current study investigated the development of monetary and social reward processes in adolescents compared with that in children and adults; furthermore, it assessed whether adolescents had different levels of sensitivity to various types of rewards. Two adapted incentive delay tasks were employed for each participant, and event-related potentials (ERPs) were recorded. The behavioral results showed that both monetary and social rewards could motivate response speed, and participants were more accurate under the monetary reward condition than under the social reward condition. The behavioral performances of individuals increased with age. For the ERP data, the cue-P3, target-P2, target-P3 and feedback-related negativity (FRN) components were investigated to identify reward motivation, emotional arousal, attention allocation and feedback processing. Children and adolescents showed higher motivation (larger cue-P3) to rewards than adults. Adolescents showed larger emotional responses to rewards; that is, they had larger target-P2 amplitudes than adults and shorter target-P2 latencies than children. Children showed stronger emotional reactivity for monetary rewards than for social rewards. All age groups had stronger attentional control (larger target-P3) under the monetary reward condition than under the social reward condition. The present study sheds light on the neurodevelopment of reward processes in children, adolescents and adults and shows that various reward process stages demonstrate different age-related and reward-type-related characteristics.
... The DRD2 gene encodes dopamine D2 receptor, which is widely spread in the striatal region of the brain and is tightly involved in reward processing (White et al., 2009). Compared to GG homozygotes, the A allele of rs1800497 is associated with reduced dopamine receptors, diminished dopaminergic activity and reduced reward sensitivity, as well as hyperactivity of HPA axis to stress, thus increasing the risk for anxiety symptoms (Alexander et al., 2011;Cohen et al., 2005;Hayden et al., 2010) ...
Article
Full-text available
Research suggests that genetic variants linked to monoaminergic neurotransmitter function moderate the association between stress and anxiety symptoms, but examining gene-environment (G × E) interactions with individual genes limits power. As one of polygenetic approaches, the multilocus genetic profile score is derived theoretically from combining the effects of multiple candidate genes based on the “biological plausibility”. Using this approach, the current study examined the interaction between monoaminergic multilocus genetic variants and stressful life events on the changes in adolescent anxiety symptoms across a one-year timespan. In a Chinese Han adolescent sample which was derived from three vocational high schools (N = 587; T1: Mage = 16.47 ± 1.53 years; 50.8%, girls), the monoaminergic multilocus genetic profile score was calculated using 5-HTR2C rs6318, TPH2 rs4570625 and DRD2 rs1800497 polymorphisms. Results showed that this monoaminergic multilocus genetic profile score interacted with stressful life events in predicting changes in anxiety symptoms. Consistent with the G×E hypothesis of differential susceptibility, adolescents with more monoaminergic plasticity alleles not only suffered more from high levels of stressful life events, which increased the risk for anxiety symptoms, but also benefited more from low levels of stressful life events, which decreased the risk for anxiety symptoms. There were no significant G × E interactions when individual polymorphisms were examined in isolation. The results highlight the importance of examining aggregated influences of multiple genes in G × E interactions underlying the longitudinal development of adolescent anxiety symptoms.
... A supplementary analysis indicates that patients with relatively lower extraversion profited most from stimulation, i.e. the stimulation effect in patients deviated during sham, but not VNS stimulation (SupplementaryFigure 3). These results are in accordance with previous studies showing that individual differences in extraversion predict reward-sensitivity in humans (e.g.37 ). However, this finding should be interpreted with caution due to the small sample size and should be corroborated in future studies. ...
Article
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Whereas the effect of vagal nerve stimulation on emotional states is well established, its effect on cognitive functions is still unclear. Recent rodent studies show that vagal activation enhances reinforcement learning and neuronal dopamine release. The influence of vagal nerve stimulation on reinforcement learning in humans is still unknown. Here, we studied the effect of transcutaneous vagal nerve stimulation on reinforcement learning in eight long-standing seizure-free epilepsy patients, using a well-established forced-choice reward-based paradigm in a cross-sectional, within-subject study design. We investigated vagal nerve stimulation effects on overall accuracy using non-parametric cluster-based permutation tests. Further, we modelled sub-components of the decision process using drift-diffusion modelling. We found higher accuracies in the vagal nerve stimulation condition compared to sham stimulation. Modelling suggests a stimulation-dependent increase of reward sensitivity and shift of accuracy-speed trade-offs towards maximizing rewards. Moreover, vagal nerve stimulation was associated with increased non-decision times suggesting enhanced sensory or attentional processes. No differences of starting bias were detected for both conditions. Accuracies in the extinction phase were higher in later trials of the vagal nerve stimulation condition suggesting a perseverative effect compared to sham. Together, our results provide first evidence of causal vagal influence on human reinforcement learning and might have clinical implications for usage of vagal stimulation in learning deficiency.
... N = 371; Suzuki, Hill, Ait Oumeziane, Foti, & Samuel, 2019). In terms of functional neuroimaging methodology, there are numerous studies linking Extraversion to dopaminergic reward regions like the ventral striatum (Canli, Sivers, Whitfield, Gotlib, & Gabrieli, 2002;Canli et al., 2001;Cohen, Young, Baek, Kessler, & Ranganath, 2005;Mobbs, Hagan, Azim, Menon, & Reiss, 2005;Schaefer, Knuth, & Rumpel, 2011;Wu, Samanez-Larkin, Katovich, & Knutson, 2014), but virtually all of the previous work on Extraversion and fMRI reward-processing was statistically underpowered, with most studies using samples under 20 participants. This raises concerns regarding the stability (Schönbrodt & Perugini, 2013), replicability, and generalizability of these effects. ...
Article
Quantitative models of psychopathology (i.e., HiTOP) propose that personality and psychopathology are intertwined, such that the various processes that characterize personality traits may be useful in describing and predicting manifestations of psychopathology. In the current study, we used data from the Human Connectome Project (N = 1050) to investigate neural activation following receipt of a reward during an fMRI task as one shared mechanism that may be related to the personality trait Extraversion (specifically its sub-component Agentic Extraversion) and internalizing psychopathology. We also conducted exploratory analyses on the links between neural activation following reward receipt and the other Five-Factor Model personality traits, as well as separate analyses by gender. No significant relations (p < .005) were observed between any personality trait or index of psychopathology and neural activation following reward receipt, and most effect sizes were null to very small in nature (i.e., r < |.05|). We conclude by discussing the appropriate interpretation of these null findings, and provide suggestions for future research that spans psychological and neurobiological levels of analysis.
... Also open to further study is the relationship between individual differences in EA and differences in neurochemistry (e.g., serotoninergic or oxytocinergic systems), especially given the effects of early life stress on these systems and EA (it is also noteworthy that women appear more sensitive to early life stress than men, as evidenced by higher basal cortisol levels in childhood (Burghy et al., 2012)). Given that individual differences in neurochemistry have heritable components (e.g., genes for different neurotransmitter receptor variants), and that other related psychological-level individual differences also appear partially heritable (e.g., personality, general intelligence), this opens up yet further research avenues for investigating plausible genetic influences on individual differences in EA (Cohen, Young, Baek, Kessler, & Ranganath, 2005;Lane et al., 1990;Lane, Sechrest et al., 1998;Munafò et al., 2003;Sauce & Matzel, 2018;Vernon, Villani, Schermer, & Petrides, 2008;Vukasović & Bratko, 2015;Wright et al., 2018). However, we want to reiterate an important conclusion drawn from our evolutionary life history perspectivenamely, that higher vs. lower EA is neither better nor worse, but rather each adaptively fits the individual's developmental niche. ...
... The converse of RDS with enhanced neuro-transmission in the reward pathway promoting appetitive response to primary re-inforcers such as food has also been linked to obesity (Volkow e al. 1999, Cohen et al 2005, Davis et al 2007. An Individual with high reward sensitivity is thought to have a reactive reward pathway that encourages hyperphagia (Pickering and Gray 2001 shown to display enhanced activity in brain regions implicated in food reward in response to palatable foods (Beaver et al 2006). ...
Conference Paper
The World Health Organization (WHO) defines obesity as a condition in which body fat is increased to the extent that health and well-being are impaired. Obesity and type-2 diabetes are two of the leading healthcare challenges facing this generation. Bariatric surgery is the most effective therapeutic option for morbid obesity. A systematic review has concluded that surgery is superior to conventional treatment in reducing weight. However, the review failed to show the superiority of one surgical method over others. It is thought that the re-routing of food through an anatomically altered and/or shorter gastrointestinal tract leads to an increased delivery of incompletely digested nutrients to the ileum and colon. This leads to over-stimulation of the specialized entero-endocrine L cells. Others argue that the exclusion of an inhibitory factor from the foregut may mediate the rapid improvement in diabetes. Several studies have shown a blunted hind gut hormone (PYY and GLP-1) response in the morbidly obese patients that is reversed by Roux-en-Y gastric bypass (RYGBP) and sleeve gastrectomy (SG). Recent studies on patients undergoing bariatric surgery have revealed a key role for PYY, GLP-1 and acyl-ghrelin in regulating appetite, bodyweight and glucose homeostasis. A correlation between changes in gut hormone secretion and weight loss has not yet been shown in humans, but has been shown in rats after RYGBP. This discrepancy may be related to study design and sample processing, as not all studies have measured the active forms of the circulating hormone, and standardized for collection of blood samples. Some have compared post-surgical changes in gut hormones against control groups, not their pre-operative state, making it difficult to draw conclusions on individual physiological changes and corresponding correlations to anthropometry. Further, no study to date has found correlation between change in active gut hormones and change in perception of hunger and satiety. In my study, RYGBP and SG led to a differential change in hunger, prospective food consumption and satiety. RYGBP had a more pronounced influence on prospective food consumption and hunger, despite non-significant changes in acyl-ghrelin. As RYGBP led to a more pronounced PYY3-36, GLP-1 and amylin response, it would be expected to alter satiety more. SG by contrast led to a more pronounced and significant decline in acyl-ghrelin, but only mediated a lesser change in hunger in comparison to RYGBP. However, my study does provide a link between the change in gut hormones and measures of appetite and satiety. My study also confirms gut hormone changes that occur after RYGBP and SG correlate to a decline in appetite and an increase in satiety, and therefore mediate weight loss. I also compared the change in hunger, prospective food consumption and satiety from baseline, and confirm a significant decrease in Δ hunger and Δ prospective food consumption, and a significant increase in Δ satiety after RYGBP and SG. There is equivalent excess weight loss (%EWL) after both RYGBP and SG at 6 weeks and 12 weeks after surgery. Despite starting with a lower BMI, the SG group lost similar BMI points to the RYGBP group at 6 weeks and at 12 weeks after surgery. This is in keeping with other recent short term and long term human studies. RYGBP and SG led to equivalent fat mass loss and decline in plasma leptin. RYGBP led to a pronounced hind gut hormone response, and SG led to a similar but less pronounced hind gut response. SG alone led to a significant decline in acyl-ghrelin. The amylin response after RYGBP and SG are divergent. In our study patients continued to lose weight from the first post-operative study point at 6 weeks to the second study point at 12 weeks, however there was no significant change in the fasting or meal stimulated insulin, PYY3-36, acyl-ghrelin, GLP-1 and amylin response from 6 to 12 weeks, apart from acyl-ghrelin in the RYGBP group, where acyl-ghrelin did increase between these time points. I also explored the role of insulin/ amylin ratio in appetite and weight loss. It is thought that an increased ratio of amylin/ insulin expression may act as a marker for beta cell dysfunction. Hyperglycaemia is thought to lead to the hypersecretion of amylin relative to insulin, and increase the amylin /insulin ratio in insulin-resistance. In the RYGBP group changes in PYY3-36 and insulin: amylin ratio correlates to weight loss. In the SG group change in PYY3-36, acyl-ghrelin, GLP-1 and amylin correlate to weight loss after surgery. RYGBP and SG seem to utilize different mechanisms to engender weight loss. The outcome after SG is dependent on the hormonal changes that ensue, whereas RYGBP may mediate its effects through neuro-anatomical changes associated with surgery. My findings, like those of others recently, lend support to the hind gut mediating the effects of weight loss after RYGBP and SG surgery. The resolution of type 2 diabetes occurs immediately after RYGBP and SG. RYGBP and SG markedly improved glucose homeostasis by improving insulin secretion through the augmented GLP-1 response, weight loss and the decrease in acyl-ghrelin secretion seen after SG, leading to improved insulin sensitivity. These changes in insulin secretion and insulin resistance are seen early after surgery before any substantial weight loss has occurred. My study confirms RYGBP and SG to be equally efficacious as metabolic surgical options. The disparity in GLP-1 response after RYGBP and SG is further complicated by the GLP-1 stimulated insulin release displaying a threshold phenomenon. Thus the GLP-1 response after RYGBP and SG did not lead to equivalent glucose-dependent insulin secretion. The GLP-1 stimulated amylin response also showed a threshold phenomenon. However, there did not seem to be any difference between the two groups. In our study there was a decline in HOMA IR after RYGBP and SG. The decline after SG showed a trend towards statistical significance. This discrepancy can partly be explained by the significant decline in acyl-ghrelin seen only after SG but not RYGBP. The duodenal exclusion hypothesis is unlikely to be a viable explanation given our results on sleeve gastrectomy, which occur in spite of a functional duodenum. The differential insulin/ amylin ratio after RYGBP and SG is noteworthy. In our study, there was a significant decrease in insulin: amylin ratio after RYGBP. Insulin secretion was not significantly altered after RYGBP. However there was an increase in amylin secretion after RYGBP leading to a decrease in insulin: amylin ratio at 6 and 12 weeks after surgery. There was a significant increase in meal stimulated insulin secretion after SG. This led to lower insulin: amylin ratio after SG. The lower amylin seen after SG may also contribute to the improved glucose homeostasis after SG, and further compensate for the relatively lower GLP-1. However, relative increase in amylin secretion did not adversely influence glucose homeostasis after RYGBP. The contrasting alteration in ratio did not correlate to satiety, prospective food consumption or weight loss. In our study GLP-1 secretion did show a positive correlation to amylin secretion in both groups, before and after surgical intervention. It is known that some patients fail to lose weight after RYGBP and SG, but the mechanisms behind this failure have yet to be explored. One patient in our SG group was noted to have lost no further weight between 3 and 12 months following surgery. This patient had a three month meal stimulated amylin, Δ PYY3-36 and Δ acyl-ghrelin curve below the baseline curve for the respective hormones. This was in sharp contrast to all the other patients in the SG group. In other words a poor hormone response after surgery predicts failure to respond after SG. This altered meal stimulated response could be utilized to fast-track patients predicted to fail to a second stage procedure. My second study suggests that an individual’s metabolic state influences their monetary decisions. The risk-sensitive monetary decisions were influenced by both long-term metabolic signals indexing energy stores and short-term metabolic signals that index energy gains. At the neurobiological level, my results suggest an overlap between food and monetary reward. This has significant implications for all decisions that incorporate risk and monetary reward. In other words an individual’s body mass index and his nutritional intake could alter risky behaviour.
... Additive effects of genes did explain the progression and risk from gambling disorder to drug addictions (Comings et al., 2001). These genetic variants were related to addictions in distinctive group or class manners, such as motivationreward (Taq 1 DRD2, homozygous 11 genotype of DRD 1 receptor), and affected both regulation (DBH, MAO-A and MAO-B;Ibanez, De Castro, Fernandez-Piqueras, Blanco, & Saiz-Ruiz, 2000) and behavioural inhibitions (Cohen, Young, Baek, Kessler, & Ranganath, 2005). This genetic liability is uniquely causal to one substance use disorder or gambling disorder. ...
... Smillie et al. (208) and co-workers reported that subjects with the DA receptor 2 (DRD2) gene A1-allele had significantly higher extroversion scores. In contrast, however, a functional magnetic resonance imaging (fMRI) study reported that A1-allele carriers exhibited lower extraversion scores, although the difference between carriers and non-carriers was not significant (217). A cross-national study of personality differences by Fischer et al. found a positive correlation between dopaminergic brain function index score and extraversion as well as a negative association between dopaminergic function and neuroticism score in those under high stress (218). ...
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... In realtà, l'ipotesi che le differenze individuali nel tratto dell'estroversione possano riflettere differenze nell'attivazione di base della corteccia si sono rivelate inconsistenti (Matthews, Gilliland, 1999;Zuckerman, 2005). L'estroversione sembra invece associata al livello di attività celebrale a riposo o in risposta a stimoli (positivi o negativi) nelle aree della corteccia medio-orbito-frontale, nel nucleus accumbens, nell'amigdala, e nel corpo striatum (Canli et al., 2002;Canli et al., 2001;Cohen et al., 2005;Deckersbach et al., 2006;Mobbs et al., 2005). Inoltre, gli individui con punteggi elevati nel tratto dell'estroversione tendono a presentare un volume maggiore della corteccia medio-orbitofrontale, un'area celebrale associata con la sensibilità alla ricompensa (DeYoung et al., 2010;Omura, Constable, Canli, 2005;Rauch et al., 2005). ...
... A variety of biological and environmental factors may impact individual differences in neurobiological responses during decision making involving risk and reward. For example, genetic variants thought to influence dopamine signaling have been linked to brain activation during decision making [42] and in response to reward processing [43,44]. Epigenetic factors may also contribute to individual differences in risk/reward processing, as a recent study showed that DNA methylation of the promoter for the dopamine transporter gene was associated with nucleus accumbens activation during loss anticipation [45]. ...
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Objective: In adolescence, sensation seeking is associated with earlier onset of alcohol use, which is a risk factor for a variety of negative consequences later in life. Individual differences in sensation seeking are related to brain function in the nucleus accumbens (NAcc), a brain region that undergoes considerable structural development during adolescence. Therefore, the goal of this study was to determine whether NAcc volume in alcohol-naive adolescents was associated with future sensation seeking and alcohol use and whether these associations differed by sex. Method: High-resolution magnetic resonance imaging was used to measure NAcc volume at baseline in 514 alcohol-naive adolescents (50.2% female) from the National Consortium on Alcohol & Neurodevelopment in Adolescence study. Direct effects of NAcc volume on adolescent drinking 2 years after baseline, and indirect effects mediated through sensation seeking 1 year after baseline, were assessed. Results: An indirect effect of NAcc volume on subsequent drinking through sensation seeking was significant for males, but not females. This effect was driven by a positive association between NAcc volume and sensation seeking observed in male, but not female, participants. A direct effect of NAcc volume on subsequent alcohol use was detected in females, but not males. In females, no association between NAcc volume and sensation seeking was detected, but NAcc volume was positively associated with future alcohol use. Conclusions: These findings suggest that delayed structural maturation of the NAcc may be a risk factor for alcohol use in adolescence; however, the mechanism by which the structure of the NAcc confers risk differs by sex.
... Whereas the "liking" component is associated with striatal opioids (Peciña & Berridge, 2000), "wanting" seems to be related to dopaminergic neurotransmission in the ventral striatum (Wyvell & Berridge, 2000). Individuals differ with respect to their sensitivity to reward and reward-predicting cues (Beaver et al., 2006;Cohen, Young, Baek, Kessler, & Ranganath, 2005;Shoaib, Spanagel, Stohr, & Shippenberg, 1995) and, in particular, "wanting" personality traits as assertiveness and reward sensitivity (i.e., drive and interest to achieve a reward) are associated with dopaminergic neurotransmission (DeYoung, 2010;Yacubian et al., 2007). The magnitude of opioid as well as dopamine release in the ventral striatum is related to the amount of pain relief (Scott et al., 2007(Scott et al., , 2008Zubieta et al., 2005), while change in the actual enjoyment of reward once it is achieved ("liking") seems to be more closely related to opioidergic than to dopaminergic neurotransmission (Drago, Caccamo, Continella, & Scapagnini, 1984;Schweinhardt, Seminowicz, Jaeger, Duncan, & Bushnell, 2009;Shimizu et al., 2004). ...
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Using electroencephalography (EEG) power measures within conventional delta, theta, alpha, beta, and gamma bands, the aims of the current study were to highlight cortical correlates of subjective perception of cold pain (CP) and the associations of these measures with behavioral inhibition system (BIS), fight-flight-freeze system (FFFS), and behavioral approach system personality traits. EEG was recorded in 55 healthy right-handed women under (i) a white noise interruption detection condition (Baseline); (ii) enduring CP induced by the cold cup test. CP and Baseline EEG band power scores within conventional frequency bands served for covariance analyses. We found that: (1) higher Pain scorers had higher EEG beta power changes at left frontal, midline central, posterior temporal leads; (2) higher BIS was associated with greater EEG delta activity changes at parietal scalp regions; (3) higher FFFS was associated with higher EEG delta activity changes at temporal and left-parietal regions, and with lower EEG gamma activity changes at right parietal regions. High FFFS, compared to Low FFFS scorers, also showed a lower gamma power across the midline, posterior temporal, and parietal regions. Results suggest a functional role of higher EEG beta activity in the subjective perception of tonic pain. EEG delta activity underpins conflict resolution system responsible for passive avoidance control of pain, while higher EEG delta and lower EEG gamma activity changes, taken together, underpin active avoidance system responsible for pain escape behavior.
... Following traumatic brain injury bad results, and Parkinson's disease [98,99]. A1 carriers have decreased glucose metabolism widely at the neuro behaviour aspect, decreased grey matter density in the substantial nigra, sub thalamic nucleus and anterior cingulate cortex (ACC), and decreased activity in the prefrontal cortex and striatum at the time of reversal learning, working memory, and receipt of monetary reward [100][101][102][103][104]. In those who are A1 allele carriers have a greater relation with greater impulsivity, bad time estimation, steeper delayed discounting, bad working memory, affected reversal learning, impaired negative outcome learning and bad long term memory [105][106][107][108]. ...
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Obesity is assuming epidemic proportions. We don't have any medical therapy that can be used for long term. Although bariatric Surgery (BS) results in immediate weight loss neither it can be afforded by all individuals nor is it safe with the comorbidities of obesity. Hence it has become essential to understand the etiopathology of increasing obesity by leaps and bounds to get a long-term sustainable cure. Volkow, et al. gave a comparison of obesity, simulating that of patients of drugs of abuse, where compulsive intake of tasty food, that is high in lipids and sugars, much >the metabolic requirements. Although hypothalamus remains the basic area where integration of circulating signals like leptin, ghrelin and nutrients occurs from the periphery further it is influenced by both higher centers along with sensory influences like tastes and smell along with emotional states. Earlier we had reviewed how different higher centers influence hypothalamus for final intake of food, here we discuss in detail the role of mesolimbic pathways as far as the rewarding part of feeding is concerned. Role of dopamine signaling, its receptors and genes controlling are further discussed in detail.
... This possibility appears plausible in light of previous research on emotion-related personality variables. As one example, the personality variable of extroversion has been strongly linked to the intensity and frequency of positive emotional reactions (Gross, Sutton, & Ketelaar, 1998;Larsen & Ketelaar, 1989, 1991Lucas & Baird, 2004;Lucas & Fujita, 2000;McCrae & Costa, 1991;Watson & Clark, 1997), as well as to genetic differences in the expression of dopamine receptor subtypes (that facilitate reward circuit activation) (Cohen, Young, Baek, Kessler, & Ranganath, 2005;Depue & Collins, 1999). As another example, the personality variable of neuroticism has been linked to the intensity of emotional reactions to negative stimuli (Larsen & Ketelaar, 1991), as well as to the "short" variant of the serotonin transporter gene (Munafò et al., 2003;Munafò, Clark, Roberts, & Johnstone, 2006). ...
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Emotional experience (EE) and trait emotional awareness (tEA) have recently become topics of considerable experimental/theoretical interest within the cognitive and neural sciences. However, to date there has been limited empirical focus on how individual differences in the factors contributing to EE (a state-based construct) might account for differences in tEA. To promote clear, well-guided empirical research in this area, in this article we first offer a concise review of the primary factors contributing to EE. We then provide a theoretical investigation into how individual differences in these factors (i.e., differences in affective response generation, affective response representation, and conscious access) could mechanistically account for differences in tEA; we also discuss plausible origins of these individual differences in light of current empirical findings. Finally, we outline possible experiments that would support (or fail to support) the role of each factor in explaining differences in tEA—and how this added knowledge could shed light on the known link between low tEA and multiple emotion-related mental and systemic medical disorders.
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The multifaceted nature of Alzheimer’s disease (AD) and Mild cognitive impairment (MCI) can lead to wide inter-individual differences in disease manifestation in term of brain pathology and cognition. The lack of understanding of phenotypic diversity in AD arises from a difficulty in understanding the integration of different levels of network organization (i.e. genes, neurons, synapses, anatomical regions, functions) and in inclusion of other information such as neuropsychiatric characteristics, personal history, general health or subjective cognitive complaints in a coherent model. Non-cognitive factors, such as personality traits and behavioral and psychiatric symptoms, can be very informative markers of early disease stage. It is known that personality can affect cognition and behavioral symptoms. The aim of the paper is to review the different types of interactions existing between personality, depression/anxiety and cognition and cognitive disorders at behavioral and brain/genetic levels.
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Personality traits are strongly related to affect, but the mechanisms accounting for this association remain mostly unclear. We test a new theoretical model that proposes that personality states, situation characteristics, and affective states mediate the relation between personality traits and trait affect. Data from an experience sampling study (N = 206; 4381 observations) indicate that personality traits are associated with personality states and experienced situation characteristics, personality states and experienced situation characteristics are associated with state affect, state affect is associated with trait affect, and that these variables indeed mediate the relation between personality traits and trait affect. These results emphasize the importance of daily experiences for trait-level variables and call for further research on the interplay between personality, behavior, situations, and affect.
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Among research disciplines, neuroscience has introduced the most fundamental changes in the way in which mental disease states are conceptualized and pursued. Nowhere is this more obvious than in translational medicine. The slow, arduous empirical process of finding new treatments must be properly incentivized for this work to be done by the current and next generation of psychiatric neuroscientists. Here, the toolboxes such as evolving biomarkers (e.g., imaging, transomic and functional biomarkers) genetics are discussed in relation to translational issues in mental diseases.
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Ett av de mest robusta fynden inom personlighets- och välbefinnandeforskning är det starka sambandet mellan personlighetsdraget extraversion och positiva emotioner, lycka samt subjektivt och psykologiskt välbefinnande. Vad som kunde förklara varför extraverta är lyckligare har i årtionden ingående undersökts, om än osystematiskt och från skilda utgångspunkter. Detta har även noterats på fältet, och för att underlätta fortsatt forskning belyser denna litteraturöversikt hur frågeställningen undersökts till dags dato. Utifrån McCraes och Costas (1991) ursprungliga uppdelning i instrumentella och temperamentella modeller samt Hampsons (2012) indelning av medierande och modererande personlighetsprocesser identifieras, systematiseras och presenteras de huvudsakliga förklaringarna som förekommer i litteraturen för sambandet mellan extraversion och lycka. Resultatet består av ett konceptuellt diagram (se Figur 1 s. 20–21) med två övergripande förklaringsmodeller, sex distinkta mekanismer, tio personlighetsprocesser och tretton hypoteser som redovisas med tillhörande forskningslitteratur. Förutom en historisk överblick över tillvägagångssätt i forskningen presenteras även aktuell metodik för personlighetsprocesser. Vidare behandlas även hur resultaten är symptomatiska för den rådande problematiken kring konceptualisering, operationalisering samt metodologi inom personlighets- och lyckoforskning, samt resultatens och socialpsykologins relevans för fortsatt forskning och befrämjande av lycka och välbefinnande. [One of the most robust findings in personality and well-being research is the strong relationship between the personality trait extraversion and positive emotions, happiness, and subjective and psychological well-being. The factors explaining why extraverts are happier has been investigated in depth for decades, albeit unsystematically and from different points of view. This has also been noted in the field, and to facilitate further research, this literature review highlights how the issue has been investigated to date. Based on the original division into instrumental and temperamental models by McCrae and Costa (1991), and the division of mediating and moderating personality processes by Hampson (2012), the main explanations that appear in the literature for the relationship between extraversion and happiness are identified, systematized, and presented. The result consists of a conceptual diagram (see Figure 1, pp. 20–21) with two overall explanatory models, six distinct mechanisms, ten personality processes, and thirteen hypotheses, which are reported with associated research literature. In addition to a historical overview of research approaches, current methodology for personality processes is also presented. Furthermore, the issue of how the results are symptomatic of the prevailing problems around conceptualization, operationalization, and methodology in personality and happiness research is also discussed, as well as the relevance of the results and social psychology for continued research and the promotion of happiness and well-being.]
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This chapter discusses neuroimaging evidence behind the processes and the developmental changes that result in behavior with fewer propensities for risky choices. Risk-taking behavior occurs throughout the lifespan, but its extent varies with age. Besides age, other factors such as personality characteristics have an impact on risk-taking behavior. Personality traits are commonly assessed using self-report questionnaires but state related factors can also be assessed using behavioral tasks. The increased neural activation observed in females compared to males may index gender differences regarding the update and valuation of uncertainty associated with risky decisions. Risks are taken with the prospect of gain but with the probability of negative consequences making the interplay between reward sensitivity and behavioral control central to risk-taking behavior on both the conceptual and neural level. Multi-modal imaging techniques should be employed alongside carefully chosen behavioral and self-report assessments.
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Based on a brief review of frequently investigated associations between measures of brain activity and personality, we argue that such links remain elusive. The following features of previous research in this field may account for the scarcity of replicable findings: (1) A focus on broad heterogeneous traits, (2) low reliability of some brain activity measures, (3) lack of well-founded theories, (4) small sample sizes, and (5) undisclosed flexibility in complex preprocessing/analysis routines for brain activity data. Furthermore, we argue that whereas (1) and (2) can be addressed within a typical single-lab study, resolving the remaining (and probably more serious) issues will benefit considerably from close cooperation among researchers with similar interests during all stages of the research cycle. We conclude by describing the ‘CoScience’ approach to cooperative research. Our initial application thereof will hopefully prove instrumental in moving the field forward.
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Recent neuroscience research is beginning to discover the brain regions involved in decision-making under uncertainty, but little is known about whether or how these regions functionally interact with each other. Here, we used event-related functional magnetic resonance imaging to examine both changes in overall activity and changes in functional connectivity during risk-taking. Results showed that choosing high-risk over low-risk decisions was associated with increased activity in both anterior cingulate and orbitofrontal cortices. Connectivity analyses revealed that largely distinct, but somewhat overlapping, cortical and subcortical regions exhibited significant functional connectivity with anterior cingulate and orbitofrontal cortices. Additionally, connectivity with the anterior cingulate in some regions, including the orbitofrontal cortex and nucleus accumbens, was modulated by the decision participants chose. These findings (1) elucidate large networks of brain regions that are functionally connected with both anterior cingulate and orbitofrontal cortices during decision-making and (2) demonstrate that the roles of orbitofrontal and anterior cingulate cortices can be functionally differentiated by examining patterns of connectivity. D 2005 Elsevier B.V. All rights reserved. Theme: Neural basis of behavior Topic: Motivation and emotion
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The orbital part of prefrontal cortex appears to be crucially involved in the motivational control of goal-directed behaviour. Patients with lesions of orbitofrontal cortex show impairments in making decisions about the expected outcome of actions. Monkeys with orbitofrontal lesions respond abnormally to changes in reward expectations and show altered reward preferences. As rewards constitute basic goals of behaviour, we investigated here how neurons in the orbitofrontal cortex of monkeys process information about liquid and food rewards in a typical frontal task, spatial delayed responding. The activity of orbitofrontal neurons increases in response to reward-predicting signals, during the expectation of rewards, and after the receipt of rewards. Neurons discriminate between different rewards, mainly irrespective of the spatial and visual features of reward-predicting stimuli and behavioural reactions. Most reward discriminations reflect the animals' relative preference among the available rewards, as expressed by their choice behaviour, rather than physical reward properties. Thus, neurons in the orbitofrontal cortex appear to process the motivational value of rewarding outcomes of voluntary action.
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The orbitofrontal cortex (OFC) is implicated in emotion and emotion-related learning. Using event-related functional magnetic resonance imaging (fMRI), we measured brain activation in human subjects doing an emotion-related visual reversal-learning task in which choice of the correct stimulus led to a probabilistically determined 'monetary' reward and choice of the incorrect stimulus led to a monetary loss. Distinct areas of the OFC were activated by monetary rewards and punishments. Moreover, in these areas, we found a correlation between the magnitude of the brain activation and the magnitude of the rewards and punishments received. These findings indicate that one emotional involvement of the human orbitofrontal cortex is its representation of the magnitudes of abstract rewards and punishments, such as receiving or losing money.
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Extraversion is a broad, multifaceted trait, yet researchers are still unsure of its defining characteristics. One possibility is that the essential feature of extraversion is the tendency to enjoy social situations. An alternative possibility is that extraversion represents sensitivity to rewards and the tendency to experience pleasant affect. In three studies, participants rated situations that varied on two dimensions: (a) whether they were social or nonsocial and (b) whether they were very pleasant, moderately pleasant, moderately unpleasant, or very unpleasant. Extraverts only rated social situations more positively than introverts did when the situations were pleasant, and extraverts also rated nonsocial situations more positively than introverts did if the situations were pleasant. Thus, the pleasantness of situations was more important than whether they were social or nonsocial in determining extraverts' and introverts' enjoyment.
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Dopamine receptor density has been shown to vary several-fold in healthy subjects. It is not clear whether this variability is due to environmental influences only or if there may be genetic contributions. Relationships between dopamine D2 receptor gene (DRD2) polymorphisms and striatal dopamine receptor density in vivo were analyzed in 56 healthy subjects who had been examined previously using positron emission tomography and the radioligand [11C]raclopride. There was a tendency for a relationship between a putative functional DRD2 promoter polymorphism (-141C Ins/Del) and dopamine D2 receptor binding potential (F = 3.05, P = 0.06). However, no significant relationships could be found between three other common silent DRD2 polymorphisms and striatal dopamine D2 receptor binding. The results suggest that DRD2 genotypes may participate in the regulation of dopamine D2 receptor density in healthy human subjects.
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Understanding the neurobiological mechanisms of addiction requires an integration of basic neuroscience with social psychology, experimental psychology, and psychiatry. Addiction is presented as a cycle of spiralling dysregulation of brain reward systems that progressively increases, resulting in compulsive drug use and a loss of control over drug-taking. Sensitization and counteradaptation are hypothesized to contribute to this hedonic homeostatic dysregulation, and the neurobiological mechanisms involved, such as the mesolimbic dopamine system, opioid peptidergic systems, and brain and hormonal stress systems, are beginning to be characterized. This framework provides a realistic approach to identifying the neurobiological factors that produce vulnerability to addiction and to relapse in individuals with a history of addiction.
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Findings from animal as well as human neuroimaging studies suggest that reward delivery is associated with the activation of subcortical limbic and prefrontal brain regions, including the thalamus, the striatum, the anterior cingulate and the prefrontal cortex. The aim of the present study was to explore if these reward-sensitive regions are also activated during the anticipation of reinforcers that vary with regard to their motivational value. A differential conditioning paradigm was performed, with the presentation of a rewarded reaction time task serving as the unconditioned stimulus (US). Depending on their reaction time, subjects were given (or not given) a monetary reward, or were presented with a verbal feedback consisting of being fast or slow. In a third control condition no task needed to be executed. Each of the three conditions was introduced by a different visual cue (CS). Brain activation of 27 subjects was recorded using event-related functional magnetic resonance imaging. The results showed significant activation of the substantia nigra, thalamic, striatal, and orbitofrontal brain regions as well as of the insula and the anterior cingulate during the presentation of a CS signalling a rewarded task. The anticipation of a monetary reward produced stronger activation in these regions than the anticipation of positive verbal feedback. The results are interpreted as reflecting the motivation-dependent reactivity of the brain reward system with highly motivating stimuli (monetary reward) leading to a stronger activation than those less motivating ones (verbal reward).
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To produce behavior, motivational states necessitate at least three fundamental operations, including (1) selection of objectives focused on goal-objects, (2) compilation of goal-object information, and (3) determination of physical plans for securing goal-objects. The second of these general operations has been theorized to involve three subprocesses: (a) feature detection and other perceptual processing of putative goal-object “rewards,” (b) valuation of goal-object worth in the context of potential hedonic deficit states, and (c) extraction of incidence and temporal data regarding the goal-object. A number of subcortical brain regions appear to be involved in these three informational subprocesses, in particular, the amygdala, sublenticular extended amygdala (SLEA) of the basal forebrain, and nucleus accumbens/subcallosal cortex (NAc/SCC). Components of the amygdala, SLEA, and NAc/SCC together constitute the larger anatomic structure of the extended amygdala. Functional magnetic resonance imaging (fMRI) studies of humans have recently begun to localize these subcortical regions within the extended amygdala during specific experimental conditions. In this manuscript, two human cocaine- infusion studies and one cognitive psychology experiment are reviewed in relation to their pattern of fMRI activation within regions of the extended amygdala. Activation in the NAc/SCC, in particular, is evaluated in relation to a hypothesis that one function of the NAc/SCC and associated brain regions is the evaluation of goal-object incidence data for the computation of conditional probabilities regarding goal-object availability. Further work is warranted to test hypothesized functions for all regions within the extended amygdala and integrate them toward an understanding of motivated behavior.
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Publisher Summary This chapter focuses on the theoretical views of extraversion. Extraversion has been included as a higher-order factor in every major taxonomic scheme of personality traits that have been developed during the past 50 years. Extraversion consistently emerges as a higher-order disposition in taxonomic schemes of personality traits. Higher-order traits represent the most general level in the hierarchy of dispositions. This is the level at which personologists attempt to explain individual differences with the fewest possible and most broadly applicable dimensions. Extraversion is divided into two distinct subfactors: (1) it involves successful adaptation through satisfying interpersonal relationships, and (2) another that entails adaptation through dominance, mastery, and achievement. Theoretical conceptualizations of extraversion have gradually but, systematically evolved over the past 75 years. This evolution necessarily involves elements of both continuity and change. The continuity is largely reflected in the interpersonal components of the trait. Recent conceptualizations have also stressed the positive affective component of the trait. These models emphasize that extraverts are happy, enthusiastic, confident, active, and energetic. More fundamentally, it now appears that extraversion essentially taps individual differences in affectively rewarding performance. Compared to introverts, extraverts view themselves as more effectively and pleasurably engaged in various aspects of their lives.
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Pathological gamblers may have a disturbance of their central nervous system noradrenergic functioning. We administered the Eysenck Personality Questionnaire to pathological gamblers and examined relationships between their personality scores on this questionnaire and indexes of noradrenergic function. There were highly significant correlations between scores on the extraversion scale and cerebrospinal fluid levels of 3-methoxy-4-hydroxyphenylglycol, plasma levels of 3-methoxy-4-hydroxyphenylglycol, urinary outputs of vanillylmandelic acid, as well as with the sum of urinary outputs of norepinephrine and its major metabolites. These results suggest that the disturbance in the central noradrenergic system in pathological gamblers may be partly reflected in their personality.
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On both psychological and physiological grounds it is suggested that the hypothesis in Eysenck's theory of introversion-extraversion attributing greater conditionability to the introvert should be replaced by the hypothesis that the introvert is relatively more sensitive to punishment and to frustrative nonreward. The data on which this conclusion is based stem chiefly from the study of eyeblink conditioning in Man as a function of personality, and from the study of the physiological locus of action of the extraverting drug, sodium amobarbital, in animals. It is suggested that the physiological basis of introversion includes, besides the Ascending Reticular Activating System, an inhibitory system comprising the orbital frontal cortex, the medial septal area and the hippocampus. This system is able to carry out the essential psychological functions believed by Eysenck to underlie introversion-extraversion. A new conception of neuroticism as reflecting degree of sensitivity to both reward and punishment is also proposed.
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To examine the possible association between three recently identified structural polymorphisms of the dopamine D2 receptor (DRD2) gene and alcoholism, we compared allele frequencies of these polymorphisms in 280 Japanese alcoholics and 289 normal controls. The results revealed that only one of three variants identified in white individuals existed in the alcoholic and control Japanese. The frequency of the Cys311 variant allele was significantly higher in alcoholics (.063) than in controls (.029). All of the subjects with the variant allele were heterozygous Ser311/Cys311. Patients with Cys311 allele had less severe symptoms of alcoholism than did those with homozygous Ser311, especially symptoms related to loss of control over drinking. The coprevalence of other psychiatric disorders including schizophrenia did not differ between