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A Theory of Limited Metabolic Energy and Premenstrual Syndrome Symptoms: Increased Metabolic Demands During the Luteal Phase Divert Metabolic Resources From and Impair Self-Control

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Abstract

Numerous studies suggest that premenstrual syndrome (PMS) may be linked to impaired self-control since many of the symptoms of PMS are indicative of impaired self-control. Evidence links PMS to increased difficulty controlling emotions, attention, and fine motor movements; increased intake of alcohol, drugs, nicotine, caffeine, and food; impaired work performance, and increased stress, aggression, criminal behavior, interpersonal conflicts, and passivity. Empirical research demonstrates that self-control is metabolically expensive and, as such, can be impaired when metabolic energy (i.e., glucose) is low or processed ineffectively. The expression of PMS is tightly linked to the luteal phase of the menstrual cycle, a time in which considerable metabolic energy is allocated to the ovaries. This increased ovarian metabolic demand could, therefore, divert energy away from, and thereby impair, other processes during this phase of the menstrual cycle. Here, we propose a novel theory in which PMS symptoms are partly attributable to the diversion of metabolic energy to the ovaries and away from processes that benefit self-control. (PsycINFO Database Record (c) 2012 APA, all rights reserved)

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... Glucose problems can increase vulnerability to self-regulation failure. For example, women experiencing premenstrual syndrome (PMS) typically have a shortage of glucose, because the reproductive demands of the luteal phase of the menstrual cycle consume extra glucose, leaving less for self-regulation (Gailliot, Hildebrandt, Eckel, & Baumeister, 2010). PMS has long been associated with increases in substance abuse. ...
... Much evidence indicates that addictive relapse occurs during periods of stress and negative emotion (e.g., Fidler & West, 2009). The increases in substance abuse during premenstrual syndrome (PMS) appear to be linked to the reduced availability of glucose for selfregulation, caused by the female body's increased metabolic demands for glucose to be allocated to reproductive functions during the luteal phase of the menstrual cycle (Gailliot et al., 2010). Even ordinary demands on self-control increase the likelihood of lapse and relapse. ...
... Moreover, systemic hypoglycemia does cause cognitive impairment despite blood glucose remaining well above normal brain-extracellular-fluid glucose levels, both in animal studies and in a large number of human studies across multiple cognitive domains (e.g., Cox et al., 1993;Weber et al., 1994;Draelos et al., 1995;Clarke et al., 1999;Strachan et al., 2000;McNay et al., 2010). Several papers in the field make the unfortunate error of confounding measurements of blood glucose with those of brain glucose (e.g., Gailliot et al., , 2010Kurzban, 2010;Beedie and Lane, 2012). We discuss this in some detail below, but it is important to note in particular that although systemic hypoglycemia causes neural glycopenia (i.e., insufficient brain glucose availability-because glucose supply from the blood is impaired), lack of fluctuation in blood glucose says nothing with regard to brain glucose depletion caused by cognitive demand (because brain glucose depletion does not affect, and is not reflected in, systemic glucose levels). ...
... Understandably, given the specialized nature of the literature, these critiques have sometimes lacked a comprehensive understanding of current research in brain glucose metabolism and supply. Similarly, both the original paper on the glucose model and follow-up papers (Gailliot et al., , 2009(Gailliot et al., , 2010 may not be appropriately constrained by the large body of work on brain glucose metabolism, or that on the modulation of cognitive function by glucose supply (specifically, in the contention that self-control is a cognitive process distinct in the magnitude of its cost from other cognitive processes). This has contributed to a lack of clarity in this area, which we hope to rectify in the following section. ...
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The brain’s reliance on glucose as a primary fuel source is well established, but psychological models of cognitive processing that take energy supply into account remain uncommon. One exception is research on self-control depletion, where debate continues over a limited-resource model. This model argues that a transient reduction in self-control after the exertion of prior self-control is caused by the depletion of brain glucose, and that self-control processes are special, perhaps unique, in this regard. This model has been argued to be physiologically implausible in several recent reviews. This paper attempts to correct some inaccuracies that have occurred during debate over the physiological plausibility of this model. We contend that not only is such limitation of cognition by constraints on glucose supply plausible, it is well established in the neuroscience literature across several cognitive domains. Conversely, we argue that there is no evidence that self-control is special in regard to its metabolic cost. Mental processes require physical energy, and the body is limited in its ability to supply the brain with sufficient energy to fuel mental processes. This article reviews current findings in brain metabolism and seeks to resolve the current conflict in the field regarding the physiological plausibility of the self-control glucose-depletion hypothesis.
... In contrast, everything that drains energy should facilitate the activation of the fatigue/decreased vitality schema. For instance, the high-energy bodily processes during the luteal phase of the menstrual cycle can increase the likelihood of self-control failure (premenstrual syndrome; Gailliot et al., 2010;Baumeister and Vohs, 2016). People high in interoceptive awareness skills may be particularly affected by energy supply or drain in terms of its effects on the fatigue/decreased vitality schema. ...
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Numerous studies confirm the so-called ego depletion effect (i.e., self-control is impaired after an initial unrelated self-control task). During recent years, the criticism on this limited-resource approach to willpower has increased, and alternative models have been developed. I argue that the existing models cannot explain the variety of results found in the ego depletion literature and introduce the schema model of self-control. Referring to related schema conceptions (i.e., illness schemas and emotion schemas), I posit that the processes that cause ego depletion effects occur around the activation of the fatigue/decreased vitality schema. This schema becomes activated via the registration of behavioral and physiological changes related to exercising self-control. The activation of the schema should instigate the motivation to conserve energy and, therefore, cause reduced effort and decreased performance in a subsequent self-control task. Moderator variables (e.g., energy supply) should influence the (non)activation of the fatigue/decreased vitality schema or its consequences.
... During the luteal phase of the menstrual cycle, the female body allocates more glucose than usual to its reproductive activities, leaving less for other things such as self-regulation. Consistent with that view, the behavioral manifestations of PMS suggest a general decline in control and restraint, as opposed to an increase in antisocial or other motivations (Gailliot, Hildebrandt, Eckel, & Baumeister, 2010). ...
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This chapter summarizes research on free will. Progress has been made by discarding outmoded philosophical notions in favor of exploring how ordinary people understand and use the notion of free will. The concept of responsible autonomy captures many aspects of layperson concepts of free will, including acting on one's own (i.e., not driven by external forces), choosing, using reasons and personal values, conscious reflection, and knowing and accepting consequences and moral implications. Free will can thus be understood as form of volition (action control) that evolved to enable people to live in cultural societies. Much work has shown that belief in free will (as opposed to disbelief) is associated with actions that are conducive to functioning well in culture, including helpfulness, restraint of aggression, learning via counterfactual analysis, thinking for oneself, effective job performance, and appropriate gratitude. Belief in free will increases in response to misdeeds by others, thus emphasizing the link to personal responsibility. Research on volition indicates that self-regulation, intelligent reasoning, decision making, and initiative all deplete a (common) limited energy source, akin to the folk notion of willpower and linked to the body's glucose supplies. Free will is thus not an absolute or constant property of persons but a variable, fluctuating capability—one that is nonetheless highly adaptive for individuals and society.
... Recently, Gailliot et al. (2010) proposed that premenstrual mood swings occur as the results of the impairment of the self-control caused by the insufficient energy resources during the luteal phase when the energy demands are increased due to intensive metabolic changes in the reproductive tracts. Here we propose that insufficient energy resources result in decreased progesterone levels and through that decreased levels of neuroactive progesterone metabolites such as allopregnanolone. ...
Article
Contradictory findings show both positive and negative effect of progesterone on the premenstrual mood changes in women. Here we present the study investigating this relationship on the large sample of premenstrual women. 122 healthy, reproductive age women collected daily morning saliva samples and recorded intensity scores for the mood symptoms: irritability, anger, sadness, tearfulness, insomnia, and fatigue. Saliva samples were assayed for progesterone concentrations and mood intensity scores were used to calculate behavioral indices. Women with low Aggression/Irritability and Fatigue had consistently higher progesterone levels during the luteal phase than women with high Aggression/Irritability and Fatigue. Additionally, Aggression/Irritability and Fatigue correlated negatively with maximal progesterone value during the luteal phase. Our results demonstrated a negative effect of low progesterone level on the premenstrual mood symptoms such as aggressive behavior and fatigue in healthy reproductive age women. This supports a previously proposed model of biphasic action of progesterone metabolites on mood.
... This hypothesis suggests that the metabolic costs of menstruation divert glucose from the brain to reproductive functions (Gailliot et al. 2010). The diversion then leads to a changes to processes in the brain that regulate self-control, leading to the 'symptoms of impulsivity' that characterize PMS (Br€ oder and Hohmann 2003; Pearson and Schipper 2009). ...
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Premenstrual syndrome (PMS) affects up to 80% of women, often leading to significant personal, social and economic costs. When apparently maladaptive states are widespread, they sometimes confer a hidden advantage, or did so in our evolutionary past. We suggest that PMS had a selective advantage because it increased the chance that infertile pair bonds would dissolve, thus improving the reproductive outcomes of women in such partnerships. We confirm predictions arising from the hypothesis: PMS has high heritability; gene variants associated with PMS can be identified; animosity exhibited during PMS is preferentially directed at current partners; and behaviours exhibited during PMS may increase the chance of finding a new partner. Under this view, the prevalence of PMS might result from genes and behaviours that are adaptive in some societies, but are potentially less appropriate in modern cultures. Understanding this evolutionary mismatch might help depathologize PMS, and suggests solutions, including the choice to use cycle-stopping contraception.
... Energy for biological and psychological processes is limited, with high activity for one process potentially reducing energy available for others (Gailliot, Hildebrandt, Eckel, & Baumeister, 2010). To the extent that hunger impairs self-control because of reduced energy availability, then it is plausible that hunger may influence energy-consuming processes other than self-control, such as immune activity or reproduction. ...
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Ten studies link hunger to reduced self-control. Higher levels of hunger-as assessed by self-report, time since last eating, or physiology-predicted reduced self-control, as indicated by increased racial prejudice, (hypothetical) sexual infidelity, passivity, accessibility of death thoughts and perceptions of task difficulty, as well as impaired Stroop performance and decreased self-monitoring. Increased rates of hunger across 200 countries predicted increased war killings, suggestive of reduced aggressive restraint. In a final experiment, self-reported hunger mediated the effect of hungry (v fed) participants performing worse on the Stroop task, suggesting a causal relationship of hunger reducing self-control.
... More broadly, processes that have especially enabled successful reproduction and evolution might tend to be more metabolically expensive [see Gailliot et al., 2010]. Evidence thus far supports the existence of three expensive psychological processes-reproduction (e.g. ...
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Aggressive and violent behaviors are restrained by self-control. Self-control consumes a lot of glucose in the brain, suggesting that low glucose and poor glucose metabolism are linked to aggression and violence. Four studies tested this hypothesis. Study 1 found that participants who consumed a glucose beverage behaved less aggressively than did participants who consumed a placebo beverage. Study 2 found an indirect relationship between diabetes (a disorder marked by low glucose levels and poor glucose metabolism) and aggressiveness through low self-control. Study 3 found that states with high diabetes rates also had high violent crime rates. Study 4 found that countries with high rates of glucose-6-phosphate dehydrogenase deficiency (a metabolic disorder related to low glucose levels) also had higher killings rates, both war related and non-war related. All four studies suggest that a spoonful of sugar helps aggressive and violent behaviors go down.
... The current work tested this hypothesis by examining whether having used self-control would decrease action and whether this effect might concern metabolism. Self-control is impaired after its use (Baumeister, Gailliot, DeWall, & Oaten, 2006;Baumeister, Vohs, & Tice, 2007;Gailliot, 2009a;Muraven & Baumeister, 2000), likely because self-control can reduce glucose in the bloodstream -yet is impaired by low glucose (DeWall, Baumeister, Gailliot, & Maner, 2008;DeWall, Gailliot, Deckman, & Bushman, 2009;Fairclough & Houston, 2004;Gailliot, in press;Gailliot, 2008Gailliot, , 2009aGailliot, , 2009bGailliot, , 2009cGailliot, 2012;Gailliot et al., 2007;Gailliot & Baumeister, 2007a;Gailliot, Hildebrandt, Eckel, & Baumeister, 2010;Gailliot, Peruche, Plant, & Baumeister, 2009;Masicampo & Baumeister, 2008). One hypothesis was that having used self-control would decrease action, or increase passivity, plausibly by depleting glucose. ...
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The capacity for action may be directly proportional to the amount of its available energy. After having used self-control, participants showed reduced action, or increased passivity, in the form of reduced activity during a social interaction (Studies 1 and 2) and less talking during a group discussion (Study 3). This effect occurred only among people who typically are highly active in such situations those with low anxieties and high extraversion. A final study suggested that the effect may be mediated by metabolism, showing that people with diabetes tend to watch more television than do people without. Action might rely on the same energy as self-control and on that which is disrupted during diabetes, indicating metabolic energy as underlying a broad capacity for action.
... In contrast, everything that drains energy should facilitate the activation of the fatigue/decreased vitality schema. For instance, the high-energy bodily processes during the luteal phase of the menstrual cycle can increase the likelihood of self-control failure (premenstrual syndrome; Baumeister & Vohs, 2016;Gailliot et al., 2010). People high in interoceptive awareness skills may be particularly affected by energy supply or drain in terms of its effects on the fatigue/decreased vitality schema. ...
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Numerous studies confirm the so-called ego depletion effect (i.e., self-control is impaired after an initial unrelated self-control task). There are also many studies on the moderators of the effect. During recent years, the criticism on this limited-resource approach to willpower has increased, and alternative models have been developed. I argue that the existing models cannot explain the variety of results found in the ego depletion literature (e.g., the vicarious depletion effect). Therefore, I sought a theoretical explanation that incorporates many of the findings, and, thus, I introduce the schema model of self-control. It is characterized by several mediating paths, with each having specific moderators. Referring to related schema conceptions already existing in the literature (i.e., illness schemas and emotion schemas), I posit that the processes that cause ego depletion effects occur around the activation of the fatigue/decreased vitality schema. This schema becomes activated via the registration of behavioral and physiological changes related to exercising self-control. The activation of the fatigue/vitality schema should instigate the motivation to conserve energy and, therefore, cause reduced effort and decreased performance in a subsequent self-control task. The moderators (e.g., energy supply) should influence the (non)activation of the fatigue/vitality schema or its consequences.
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The current study examined whether changes in glucose during a self-control task would predict changes in self-control performance later on. Participants attended two experimental sessions, spaced two weeks apart. During each session, they had their glucose measured, completed the Stroop task as a measure of self-control, and then had their glucose measured again. Larger decreases in glucose (from before to after the Stroop task) during the first session predicted larger increases in improvement on the Stroop task dur- ing the second session, in the form of increased speed. Learning self-controlmight benefit from using lar- ger amounts of glucose. Learning self-control is metabolically expensive. These findings raise the possi- bility that self-control fatigue occurs because metabolic energy is depleted during the learning of self- control.
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To explore specific psychiatric comorbidity among type II DM patients with poor and good glycemic control. One hundred four patients with type II DM attending outpatient department of the Endocrinology Unit of Süleyman Demirel University Medical Faculty were included in this study. Patients were divided into two groups according to HbA1c level: >7% defined group 1 with poor glycemic control (n=40), and <7% defined group 2 with good glycemic control (n=64). All patients were assessed using a semi structured sociodemographic data form, the Structured Clinical Interview for DSM-IV-Clinical Version (SCID-I/CV), Hamilton Depression Rating Scale (HDRS), Hamilton Anxiety Rating Scale (HARS) and the Minimental State Examination Scale. The prevalence rate of psychiatric disorders were as follows: major depressive disorder 67.5%, dysthymic disorder 10.0%, generalized anxiety disorder 7.5%, obsessive compulsive disorder 5%, social phobia 2.5% and nicotine dependence 5% in group 1 patients; and major depressive disorder 43.8%, dysthymic disorder 10.9%, paranoid disorder 3.1%, obsessive compulsive disorder 6.3%, social phobia 4.7%, generalized anxiety disorder 6.3%, nicotine dependence 9.4% and alcohol dependence 3.1% in group 2 patients. Major depressive disorder frequency was significantly higher in group1 patients than group 2 patients. HDRS and HARS scores were significantly higher in group 1 patients than in group 2 patients. Significant positive correlations were found between HDRS, HARS scores, number of depressive episodes and the level of HbA1c in the diabetic patients. Major depressive disorder was more frequent in diabetic patients with poor glycemic control than in those with good glycemic control. There was a strong association between level of HbA1c and depression and anxiety symptom level.
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The lifetime prevalence of psychiatric illness was determined in 114 patients with diabetes mellitus (types I and II) who were selected randomly from patients undergoing diabetes evaluations at a large medical center. The relationship of psychiatric illness to diabetic control was studied using glycosylated hemoglobin (HbAi) and self-report measures of metabolic symptoms. Seventy-one percent of the patients had a lifetime history of at least one criteria-defined psychiatric illness; affective and anxiety disorders were the most common diagnoses. A significant difference (p=.02) in mean glycosylated hemoglobin levels was observed comparing patients with a recent psychiatric illness (X=10.8%) to those never psychiatrically ill (X=9.6%). These psychiatrically ill patients also- reported more symptoms of poor metabolic control and more distress associated with these symptoms than did patients never psychiatrically ill (p<.0001 for both). The overall report of diabetes symptoms was unrelated to HbA1 (p=.25) and was influenced primarily by the recent presence of psychiatric disorder (p<.0001). We conclude that emotional illness is associated with both poorer metabolic control and the increased report of clinical symptoms of diabetes.
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Numerous insects, including Drosophila nigrospiracula, that inhabit necrotic cacti of the Sonoran desert are host to Macrocheles subbadius, a cosmopolitan mesostigmatid mite. This paper shows that the mite pierces Drosophila integument and ingests haemolymph while attached to the abdomen of its host. Among field-caught flies, there was a strong negative relationship between mite load and wet mass of adult flies of both sexes. Thus, M. subbadius is an ectoparasite of D. nigrospiracula, contrary to the widespread belief that macrochelids form only phoretic associations with adult flies. The parasite harms its host in many ways. Under laboratory conditions, there was a significant negative effect of mite load on survivorship. In the field, there was a significant negative relationship between mite load and number of eggs carried by sexually mature females, suggesting that infested females resorb their oocytes to compensate for nutritional stress imposed by feeding mites. Likewise, in the laboratory, infestation lengthened somewhat the period prior to onset of oviposition, and decreased the number of eggs laid by females over their life. However, mite-infested females maintained on a yeast-supplemented diet overcame the potentially debilitating effects of mites, and were actually slightly, but not significantly, more fertile than uninfested females. Since the dietary conditions of flies influenced the degree to which fecundity was affected, the debilitating effect of mites is comparable to that of starvation. This conclusion derives support from the observation that laboratory females infested for 4 d, but whose mites were subsequently removed, produced fewer progeny than uninfested females. Although this effect was significant only among old females, it nevertheless indicates that the observed effects of mites on fecundity are not the result of mechanical constraints on oviposition behavior. Since intensities of infestation used in laboratory experiments were similar to those encountered in nature, observed ectoparasitic effects on fly fitness suggest that M. subbadius can reduce fly numbers in nature.
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Past work suggests that executive functioning relies on glucose as a depletable energy, such that executive functioning uses a relatively large amount of glucose and is impaired when glucose is low. Glucose from the bloodstream is one energy source for the brain, and glucose stored in the brain as glycogen is another. A review of the literature on glycogen suggests that executive functioning uses it in much the same way as glucose, such that executive functioning uses glycogen and is impaired when glycogen is low. Findings on stress, physical persistence, glucose tolerance, diabetes, sleep, heat, and other topics provide general support for this view. © 2008 Association for Psychological Science.
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Recent findings indicate that frontal brain asymmetry may be a marker of for depression. However, the psychological predispositions that account linkage between frontal brain asymmetry and depression are unclear. approach-withdrawal hypothesis is the primary framework that has been to account for the linkages between frontal brain asymmetry and or emotional disorders. We review evidence consistent with this and suggest several directions for its extension. One such direction is to constrain the approach-withdrawal hypothesis by linking frontal asymmetry to the known functions of the prefrontal cortex. On this we propose that frontal brain asymmetry may be preferentially linked processes that promote the temporal continuity and shifting of or emotional priorities and the suppression of interference by sources of motivation or emotion. We review evidence from and neurobiological studies of depression that is broadly consistent with these predictions. We emphasise the need for future studies testing our hypotheses.
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The purpose of this review is to collate and evaluate critically recent reports on the effect of diet and nutritional supplements on the symptoms of pre-menstrual syndrome (PMS). Evidence is provided of a poor dietary intake and vitamin and mineral deficiencies in subjects with PMS. The review explains 'the four-phase dietary treatment for PMS' used at the University College London Hospital's PMS Clinic, and the author's own experience derived from seeing many PMS patients over 6 years is briefly presented. From the available evidence, it appears that the diet advocated in the Health of the Nation document is also the best approach to treating PMS. As regards supplements, there is certainly evidence that magnesium and vitamin B are helpful to some women. Evening primrose oil 6 seems most effective when used to treat mastalgia. Evidence is emerging that calcium supplementation may also lessen some PMS symptoms. Beneficial effects are usually noticed only after following specific dietary advice for 3-4 months. This may cause some sufferers to lose patience with the dietary approach. Nutritional guidelines should be advocated as the first-line approach for PMS. It is cheap, effective and puts the woman in control of her own treatment. Evidence is accumulating for the role of neurotransmitters in PMS. It is known that diet can affect neurotransmitter metabolism but more research needs to be focused on this area.
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This paper is an overview of research on premenstrual syndrome (PMS), focusing on the key topics of definition of the syndrome and the relationship of PMS to psychiatric illness. The etiology and treatment of PMS is discussed. Medical-legal implications of PMS are also reviewed with attention directed to the few studies and court cases relating PMS to the concept of diminished criminal responsibility. Researchers are beginning to make some progress with respect to criteria for the diagnosis of PMS. Much work remains concerning the questions of the relationship of PMS to psychiatric disorders and whether PMS should be considered as one syndrome or many.
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The abstract for this document is available on CSA Illumina.To view the Abstract, click the Abstract button above the document title.
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The United States is becoming increasingly diverse, yet interracial contact continues to be awkward, if not stressful, for many. Indeed, recent research suggests that individuals often exit interracial interactions feeling drained both cognitively and emotionally. This article reviews research examining how interracial encounters give rise to these outcomes, zeroing in on the mediating role of self-regulation and the moderating influence of prejudice concerns. Given that interracial contact may be the most promising avenue to prejudice reduction, it is important to examine factors that undermine positive interracial contact experiences, as well as those that facilitate them.
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A fundamental assumption of coevolutionary models of host-parasite relations is that resistance is costly. Costs are envisioned as phenotypic or genetic trade-offs in the allocation of limited resources to specific tasks. Using workers of the bumble bee Bombus terrestris L., we tested experimentally whether foraging effort, an energetically costly and crucially important task that ensures colony growth, survival and reproduction, is costly in terms of reduced resistance against parasite attack. The experiment showed that indeed workers allowed to forage showed lower levels of immunocompetence, as measured by the degree of encapsulation of a novel antigen, than workers prevented from foraging activity.
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The effects of premenstrual syndrome (PMS) on the marital relationship of husband and wife in both the follicular and luteal menstrual cycle phases for couples with women experiencing PMS as compared to a control group of similar, non-PMS couples were tested. The specific purpose of the study was to determine if couples differed in their level of marital distress from the woman's follicular to luteal cycle phases. Results indicated that the marital relationship of PMS couples was similar to non-PMS couples in the follicular cycle phase. However, the marital relationship of PMS couples deteriorated in the luteal cycle phase. Males' and females' reports of marital functioning were similar. Many female participants tested as experiencing a high rate of ongoing psychosocial distress.
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The handicap hypothesis of honest signaling suggests that secondary sexual characters reliably reflect phenotypic or genotypic quality of signalers. This hypothesis is based on the assumptions that signals are costly to produce and/or maintain and the cost of a given level of signaling is higher for low quality than for high quality signalers. We tested these assumptions in a field experiment in which the size of a secondary sexual character [tail length in male barn swallows (Hirundo rustica)] was experimentally manipulated. Males were randomly assigned to tail elongation, tail shortening, or two control treatments (tail manipulation, or just capture, ringing, and handling). Male barn swallows were challenged with an injection of sheep red blood cells, and blood was sampled on the day of first capture and after 3 to 4 weeks for determination of concentrations of gamma-globulins. Tail-elongated males did not increase levels of gamma-globulins while males of the other three groups demonstrated increases. Analyses of variation in gamma-globulins within treatment groups revealed a positive correlation between gamma-globulins and original tail length among males with elongated tails. These results suggest that tail length imposes an immu-nocompetence cost on males, and that males with naturally long tails are differentially better able to cope with this cost.
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This study investigated the effects of menstrual cycle phase on aggression in two groups of women, which differed in the severity of their self-reported perimenstrual symptoms. A low- and a high-symptom group were recruited using the Menstrual Distress Questionnaire (MDQ) to define the groups. Twenty-two subjects (11 low and 11 high symptom) participated across one menstrual cycle: during the premenstrual, menstrual, midfollicular, and ovulatory phases. The Point Subtraction Aggression Paradigm was used to assess aggression on each day of participation. There were three main findings; a) rates of aggressive responding did not vary across phases of the menstrual cycle; b) the high-symptom group emitted higher rates of aggressive responding across the menstrual cycle than did the low-symptom group; and c) rates of aggressive responding correlated with the MDQ's behavioral and psychological scales and not the somatic scales. These findings indicate that the menstrual cycle phase does not differentially affect this laboratory measure of aggression. The differences found between the two symptom groups parallel a few reports indicating that women who differ in retrospectively reported mood and behavioral changes related to their menstrual cycle also differ on a number of other psychometric measures. Aggr. Behav. 24:9–26, 1998. © 1998 Wiley-Liss, Inc.
Article
The brain is a very expensive organ in metabolic terms. Each unit of brain tissue requires over 22 times the amount of metabolic energy as an equivalent unit of muscle tissue. There is no correlation across mammals, however, between the relative size of the brain and the relative basal metabolic rate. The Expensive Tissue Hypothesis explains this apparent paradox by looking at the metabolic cost of the brain in the context of the costs of other metabolically expensive organs in the body. The results show that the increase in brain size in humans is balanced by an equivalent reduction in the size of the gastro-intestinal tract. In other words, the increased energetic demands of a relatively large brain are balanced by the reduced energy demands of a relatively small gastro-intestinal tract. This relationship also seems to be true in non-human primates. The size of the gastro-intestinal tract is dependent on both body size and the quality of the diet. It is argued that humans (and other primates) could not have developed a relatively large brain without also adopting a high quality diet that would have permitted a reduction in the relative size of the gastro-intestinal tract. Dietary change is therefore viewed as a 'prime releaser' in brain evolution. It is argued that a high quality diet is necessary for the evolution of a relatively large brain. However, the change to such a high quality diet, which involved an increased proportion of animal based products, need not have been one of the 'prime movers' in brain evolution. In this context, and based on the archaeological and palaeoanthropological record, the factors most probably surrounding the evolution of the human brain are discussed.
Article
Brain tissue is metabolically expensive, but there is no significant correlation between relative basal metabolic rate and relative brain size in humans and other encephalized mammals. The expensive-tissue suggests that the metabolic requirements of relatively large brains are offset by a corresponding reduction of the gut. The splanchnic organs (liver and gastro-intestinal tract) are as metabolically expensive organs in the human body that is markedly small in relation to body size. Gut size is highly correlated with diet, and relatively small guts are compatible only with high-quality, easy-to-digest food. The often -cited relationship between diet and relative brain size is more properly viewed as a relationship between relative brain size and relative gut size, the latter being determined by dietary quality. No matter what is selecting for relatively large brains in humans and other primates, they cannot be achieved without a shift to a high-quality diet unless there is a rise in the metabolic rate. Therefore the incorporation of increasingly greater amounts of animal products into the diet was essential in the evolution of the large human brain.
Article
Consistently with previous studies, female red jungle fowl (Gallus gallus) preferred to mate with males with longer, redder combs, but paid little attention to plumage characters. Individual variation in comb length was positively correlated with plasma testosterone level. Males with longer combs had fewer circulating lymphocytes, as would be expected if maintenance of secondary sexual characters is costly to the immune system.
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Provides an overview of evolutionary trends in the Hydrachnidia (=Hydracarina), then examines host and site selection, engorgement on the host, population and community structure, and the effects of these parasites on aquatic insects. -from Author
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Purpose ? The aim of this study is to investigate the prevalence of appetite-related, emotional and physical symptoms in a group of menstruating females. Design/methodology/approach ? A total of 20 Caucasian females, aged 17-24 years, completed a specifically designed menstruation symptoms diary for one cycle length. Findings ? The findings of the study indicate that changes in appetite and physical and emotional symptoms accord with hormonal changes in the premenstrual and bleed phases of the cycle. Research limitations/implications ? The implication of using a daily diary to identify symptoms demonstrates a record of the individuals? perceptions of their symptoms and is therefore only subjective. The prevalence of appetite-related symptoms was reported in the diaries but the quantity of food and drink consumed, and therefore energy intake could not be established for any of the endocrine phases. Originality/value ? Conducted on a very small scale this study can be considered as being a pilot for a more rigorous investigation into the understanding of diet in the identification and management of premenstrual syndrome.
Article
I analyzed male mandible and wing allometries in natural population samples of 76 species in 9 genera of the family Lucanidae. Positive allometry of mandible size to body size was highly significant in all the species, and negative allometry of wing size was significant in 72 species. Negative allometry of wing size was not related to phylogenetic background, suggesting developmental tradeoffs between resource allocations to mandible and wing structures. Wing allometry was correlated negatively with mandible allometry and with the proportion of mandible size to body size, suggesting that species with relatively large mandibles have proportionally smaller wings. There is an inherent negative correlation between mass of beetles and wing area per unit mass, and negative wing allometry further influences this linear relationship. Negative wing allometry may reflect a morphological cost to evolving oversized mandibles.
Article
GLUT4, the insulin-responsive glucose transporter, plays an important role in postprandial glucose disposal. Altered GLUT4 activity is suggested to be one of the factors responsible for decreased glucose uptake in muscle and adipose tissue in obesity and diabetes. To assess the effect of GLUT4 expression on whole-body glucose homeostasis, we disrupted the murine GLUT4 gene by homologous recombination. Male mice heterozygous for the mutation (GLUT +/-) exhibited a decrease in GLUT4 expression in adipose tissue and skeletal muscle. This decrease in GLUT4 expression did not result in obesity but led to increased serum glucose and insulin, reduced muscle glucose uptake, hypertension, and diabetic histopathologies in the heart and liver similar to those of humans with non-insulin-dependent diabetes mellitus (NIDDM). The male GLUT4 +/- mice represent a good model for studying the development of NIDDM without the complications associated with obesity.
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Variations of the self-imposed delay-of-gratification situation in preschool were compared to determine when individual differences in this situation may predict aspects of cognitive and self-regulatory competence and coping in adolescence. Preschool children from a university community participated in experiments that varied features of the self-imposed delay situation. Experimental analyses of the cognitive–attentional processes that affect waiting in this situation helped identify conditions in which delay behavior would be most likely to reflect relevant cognitive and attentional competencies. As hypothesized, in those conditions, coherent patterns of statistically significant correlations were found between seconds of delay time in such conditions in preschool and cognitive and academic competence and ability to cope with frustration and stress in adolescence. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Article
Background: The objective of this study was to evaluate the pretreatment psychosocial functioning of women with premenstrual dysphoric disorder (PMDD) and the effect of sertraline treatment on psychosocial functioning in these patients. Method: Two hundred forty-three women recruited from 12 university-affiliated sites and meeting DSM-IV criteria for PMDD completed 1 cycle of single-blind placebo and were randomly assigned to flexible dose sertraline or placebo for 3 cycles. Psychosocial functioning was assessed by the Daily Record of Severity of Problems (DRSP), the Social Adjustment Scale (SAS), and the Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q). Results: SAS scores during the follicular phase were similar to SAS scores of community norms, whereas the pretreatment SAS and Q-LES-Q scores during the luteal phase were similar to scores of women with depressive disorders. Sertraline was significantly more effective than placebo in improving psychosocial functioning as measured by the SAS, the Q-LES-Q, and the 3 DRSP items of impaired productivity, interference with social activities, and interference with relationships with others. Improvement in psychosocial functioning assessed by SAS and Q-LES-Q correlated with improvement in symptomatology assessed by the Clinical Global Impressions-Improvement (CGI-I) scale and the Hamilton Rating Scale for Depression (HAM-D). Remitters (CGI-I score of 1) were more likely to function better at baseline and showed larger improvements in functioning and quality of life with treatment compared with nonremitters. Conclusion: Sertraline was superior to placebo in improving psychosocial functioning in women with PMDD as reflected by SAS, Q-LES-Q, and DRSP measures. Functional improvement correlated with improvement in premenstrual symptomatology and was apparent by the second cycle of treatment. Comparison of pretreatment SAS scores in women with PMDD with the scores of other populations of women documents the degree of luteal phase functional impairment in women with PMDD and a relative absence of follicular phase impairment.
Article
Administered questionnaires to 300 women complaining of premenstrual tension syndrome (PMTS) in Virginia to provide preliminary data concerning the efficacy of a systems-oriented family somatic approach to the problem. Ss were recruited through the Premenstrual Syndrome Clinic at the Medical College of Virginia Hospital and private clinics in the Richmond area of Virginia. The survey instruments—which included the Menstrual Distress Questionnaire by R. H. Moos (1977), the Waring Intimacy Questionnaire by E. M. Waring (1983), and the Renne Index of Marital Satisfaction by the California Department of Public Health (1970)—were completed by 156 Ss. Data from the 130 Ss involved in an intimate dyadic relationship indicated that dyadic intimacy and marital satisfaction were problematic for women with PMTS and the degree of dyadic dysfunction was related to the degree of symptom severity. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Article
Serum hormone concentrations were determined at intervals during the last 17 days of the menstrual cycle in 35 patients with premenstrual tension (PMT) and 11 control subjects without symptoms. The maximum mean concentration of oestradiol occurred 17 days before menstruation in the patients and 14 days before in the controls. The maximum concentrations of progesterone were similar in the two groups but the mean concentrations rose carlier in the cycle in the patients with PMT. These results suggested that the patients tended to ovulate earlier in the cycle than the controls and on the basis of the ovulatory surge in gonadotrophins two groups could be identified, group A who showed signs of ovulation 14 days or less before menstruation (17 patients, 9 controls) and group B who ovulated more than 14 days before menstruation (18 patients, 2 controls). There were no significant differences between the groups in prolactin, thyroid stimulating hormone or testosterone levels, but cortisol concentrations were uniformly higher in both groups of patients compared with those in the controls. Follicular growth was assessed with ultrasound in 18 patients and 16 control subjects. Mean follicular diameters were significantly lower in the patients than in the control group at the time of ovulation. Oestradiol determinations done at the same time correlated with the diameters and were also significantly lower in the patient group. The results suggest that ovulation tends to occur prematurely in women with PMT.
Article
The purpose of this study was to examine the relationships among perceived stress, ovarian steroids (estradiol and pregnanediol), stress arousal indicators (cortisol, catecholamines) and premenstrual symptoms (turmoil, fluid retention). Women (N = 74) with low symptom severity (LS), premenstrual syndrome (PMS), or premenstrual magnification (PMM) symptom patterns provided daily urine samples over one cycle and recorded their symptoms and perceived stress levels in a health diary. Multiple regression analysis was used to test models of premenstrual symptoms in separate analyses for women with the LS and PMS symptom patterns and the LS and PMM symptom patterns. Data from the LS and PMS groups revealed that greater stress ratings accounted for turmoil symptoms and higher luteal phase cortisol levels for fluid retention symptoms. For LS and PMM groups, lower luteal phase norepinephrine levels, higher global stress ratings, and a more gradual drop in estradiol premenses accounted for turmoil symptoms. Premenses norepinephrine and epinephrine levels and premenses stress ratings accounted for fluid retention. These findings support an important relationship among perceived stress, stress arousal indicators, and premenstrual symptoms that differs for women with a PMS and PMM symptom pattern. © 1998 John Wiley & Sons, Inc. Res Nurs Health 21: 129–142, 1998
Article
Twenty-four women with a diagnosis of premenstrual dysphoric disorder (PMDD) and 18 controls took part in a study of patterns of female aggression. They completed a version of the Conflict Tactics Scale for a premenstrual and a follicular phase of their menstrual cycle and for the past year. The Life History of Aggression was completed during a clinician interview. The women used more aggressive tactics to solve conflicts in the premenstrual than in the follicular phase, but the difference was only significant for the PMDD group. During the past year, reasoning was the most common strategy used by women to resolve conflicts, but verbal aggression was also prevalent. Although physical violence was less common, the prevalence of any act of violence was 33% in the controls and 62% in the clinical group. Women with PMDD used both verbal and physical aggression more frequently than the controls and had a higher lifetime history of aggression. Aggression by women toward partners was associated with a general tendency to act aggressively. Aggr. Behav. 29:228–238, 2003. © 2003 Wiley-Liss, Inc.