Dienstag, 30. April 2013

Intelligence and past use of recreational drugs

Intelligence and past use of recreational drugs
Daniel R Wilmoth; 2012
http://emilkirkegaard.dk/en/wp-content/uploads/Intelligence-and-past-use-of-recreational-drugs.pdf


Abstract

One motivation for trying recreational drugs is the desire for novel experiences. More intelligent people tend to value novelty more highly and may therefore be more likely to have tried recreational drugs. Using data from a national survey, it is shown that intelligence tends to be positively related to the probabilities of having tried alcohol, marijuana, cocaine and several other recreational drugs. Evidence is also presented that those relationships typically disappear or change sign at high levels of intelligence. These patterns persist after accounting for a wide range of personal characteristics.




e.g. Fig.1.:

Montag, 29. April 2013

Runaway cultural niche construction

Runaway cultural niche construction
Luke Rendell et al.; 2011
http://lalandlab.st-andrews.ac.uk/documents/Publication161.pdf


Abstract

Cultural niche construction is a uniquely potent source of selection on human populations, and a major cause of recent human evolution. Previous theoretical analyses have not, however, explored the local effects of cultural niche construction. Here, we use spatially explicit coevolutionary models to investigate how cultural processes could drive selection on human genes by modifying local resources. We show that cultural learning, expressed in local niche construction, can trigger a process with dynamics that resemble runaway sexual selection. Under a broad range of conditions, cultural niche-constructing practices generate selection for gene-based traits and hitchhike to fixation through the build up of statistical associations between practice and trait. This process can occur even when the cultural practice is costly, or is subject to counteracting transmission biases, or the genetic trait is selected against. Under some conditions a secondary hitchhiking occurs, through which genetic variants that enhance the capability for cultural learning are also favoured by similar dynamics. We suggest that runaway cultural niche construction could have played an important role in human evolution, helping to explain why humans are simultaneously the species with the largest relative brain size, the most potent capacity for niche construction and the greatest reliance on culture.

Samstag, 27. April 2013

The Relationship Between Multiple Sex Partners and Anxiety, Depression, and Substance Dependence Disorders: A Cohort Study

The Relationship Between Multiple Sex Partners and Anxiety, Depression, and Substance Dependence Disorders: A Cohort Study
Sandhya Ramrakha at al.; 2013
http://www.moffittcaspi.com/sites/moffittcaspi.com/files/field/publication_uploads/Ramrakha_2013_MSPartners.pdf


Abstract

Changes in sexual behavior have resulted in longer periods of multiple serial or concurrent relationships. This study investigated the effects of multiple heterosexual partners on mental health, specifically, whether higher numbers of partners were linked to later anxiety, depression, and substance dependency. Data from the Dunedin Multidisciplinary Health and Development Study, a prospective, longitudinal study of a birth cohort born in 1972–1973 in Dunedin, New Zealand were used. The relationship between numbers of sex partners over three age periods (18–20, 21–25, and 26–32 years) and diagnoses of anxiety, depression, and substance dependence disorder at 21, 26, and 32 years were examined, using logistic regression. Interaction by gender was examined. Adjustment was made for prior mental health status. There was no significant association between number of sex partners and later anxiety and depression. Increasing numbers of sex partners were associated with increasing risk of substance dependence disorder at all three ages. The association was stronger for women and remained after adjusting for prior disorder. For women reporting 2.5 or more partners per year, compared to 0–1 partners, the adjusted odd ratios (and 95 % CIs) were 9.6 (4.4–20.9), 7.3 (2.5–21.3), and 17.5 (3.5–88.1) at 21, 26, and 32 years, respectively. Analyses using new cases of these disorders showed similar patterns. This study established a strong association between number of sex partners and later substance disorder, especially for women, which persisted beyond prior substance use and mental health problems more generally. The reasons for this association deserve investigation.

Donnerstag, 25. April 2013

Conservatives are happier than liberals, but why? Political ideology, personality, and life satisfaction

Conservatives are happier than liberals, but why? Political ideology, personality, and life satisfaction
Barry R Schlenker et al.; 2012
http://www.psych.ufl.edu/~chambers/Chambers_JRP_PDF.pdf


Abstract

Political conservatives are happier than liberals. We proposed that this happiness gap is accounted for by specific attitude and personality differences associated with positive adjustment and mental health. In contrast, a predominant social psychological explanation of the gap is that conservatives, who are described as fearful, defensive, and low in self-esteem, will rationalize away social inequalities in order to justify the status quo (system justification). In four studies, conservatives expressed greater personal agency (e.g., personal control, responsibility), more positive outlook (e.g., optimism, self-worth), more transcendent moral beliefs (e.g., greater religiosity, greater moral clarity, less tolerance of transgressions), and a generalized belief in fairness, and these differences accounted for the happiness gap. These patterns are consistent with the positive adjustment explanation.

Emotional Sex Differences:

>Although there are a few exceptions, the majority of studies reveal that women express emotions more frequently and intensely (e.g., wider smile) than men (Buck, Savin, Miller & Caul, 1972; J.J. Gross & John, 1998; Kring & Gordon, 1998; Vigil, in press), although women's and men's expressiveness is moderated by social context (Buck, Miller, & Caul, 1974; M.L. Hoffman, 1977). Gross and John identified five affective facets or subdomains that are common across measures of emotions and feelings: expressive confidence (the ability to act out emotions without feeling them), positive expressivity (the expression of positive emotions), negative expressivity, impulse intensity (intensity of feelings and difficulty controlling their expression), and masking (suppression of feelings). There were no sex differences in expressive confidence, but about 3 out of 4 women reported more positive expressivity than the average man, and 2 out of 3 reported more negative expressivity than the average man.
...
Wether women or men have more intense feelings - that is, unobservable personal experience of an emotion - is not clear. The phenomenon is obviously more difficult to study than observable emotions, but it has nonetheless been assessed using self-report, physiological reactivity, and brain imaging methods. Women typically report more intense feelings than men (Buck, Miller, & Caul, 1974; M. Grossman & Wood, 1993). Using diary methods, Barrett, Robin, Pietromonace, and Eysell (1998) found that women and men reported a similar range of emotions during day-to-day social interactions, but women rated the intensity of their accompanying feelings higher than did men. In their analysis of multiple emotions and feelings scales, Gross and John (1998) found that 6 out of 7 women reported more intense emotional impulses - difficulty in inhibiting the expression of feelings - than did the average man, whereas 2 out of 3 men reported more masking than did the average woman.

The physiological and brain imaging studies reveal a much more nuanced picture. Sometimes women show more intense physiological reactivity (e.g., sweating) than men to affect-eliciting situations (e.g., viewing an injury), consistent with their reports of more intense feelings, but sometimes they do not (Eisenberg & Lennon, 1983; Gard & Kring, 2007; Wager, Plan, Liberzon, & S.F. Taylor, 2003). Buck et al. (1974) found disconnections between expressed emotions, reported intensity of accompanying feelings, and physiological indicators of affective reactivity. In situations designed to elicit a range of affective reactions, more women than men expressed emotions, reported intense reactions, but showed little physiological indication of reactivity. In support of Grossand John's (1998) finding that men report more masking, Buck et al. found more men than women inhibited emotional expressions, reported less intense feelings, but at the same time showed stronger physiological reactivity to the situation.
...
In a meta-analysis of brain imaging studies in this area, Wager et al. (2003) found no evidence for more overall brain activation in women than in men during the processing of affective information (e.g., car accident), but there were sex differences in the pattern of activation. The brain activity of men suggested that they focus more on the "sensory aspects of emotional stimuli and tend to process them in terms of implications for required actions, whereas women direct more attention to the feeling state engendered by the emotional stimuli". If Wager et al. are correct, many women experience feelings in a more personally intense way than men.

Men's masking of their feelings is consistent with both socialization and the dynamics of male-male competition. ...  The disconnection between emotions and feelings in many women is intriguing and suggests some women are using emotional expressions strategically. These women are not experiencing the corresponding feelings but are expressing the emotion for social effect.
...<

Male, Female - The Evolution of Human Sex Differences
David C. Geary; 2010

On the genetic basis of face cognition and its relation to fluid cognitive abilities

On the genetic basis of face cognition and its relation to fluid cognitive abilities
A. Kiy et al.; 2013
Genes, Brain & Behavior


Abstract

The oxytocin and the dopaminergic systems have turned out to be highly relevant for social abilities and cognition. Therefore, we examined the association between two functional gene polymorphisms and face cognition (FC) in a multivariate study (N = 250) by applying structural equation modeling. The catechol-O-methyltransferase (COMT) val158met polymorphism influences the enzyme activity of COMT, which affects the prefrontal dopamine concentration. The rs226849 is a single-nucleotide polymorphism located in the promoter region of the oxytocin receptor (OXTR) gene, modulating the mRNA expression. By modeling a general fluid ability factor (defined by working memory and reasoning) and nested FC factors, we tested genetic contributions to FC, after controlling for variance in FC that was also associated with fluid abilities. In line with several previous studies, we found a significant association between the COMT genotype and fluid abilities (Gf) but not with FC. The association between the oxytocin polymorphism and Gf was opposite in direction for men and women. Women with the C+ genotype performed better on Gf tasks than those with the Cgenotype. Conversely, men with the C genotype performed better than those with the C+ genotype. There was no significant association between OXTR and the nested FC factor. Therefore, the relationship between the oxytocin polymorphism and FC can be fully accounted for by Gf. The sex specificity of this relationship is a novel finding and warrants a mechanistic explanation.

Longitudinal evidence that fatherhood decreases testosterone in human males

Longitudinal evidence that fatherhood decreases testosterone in human males
Lee T Gettler et al.; 2011
http://www.pnas.org/content/108/39/16194.full


Abstract

In species in which males care for young, testosterone (T) is often high during mating periods but then declines to allow for caregiving of resulting offspring. This model may apply to human males, but past human studies of T and fatherhood have been cross-sectional, making it unclear whether fatherhood suppresses T or if men with lower T are more likely to become fathers. Here, we use a large representative study in the Philippines (n = 624) to show that among single nonfathers at baseline (2005) (21.5 ± 0.3 y), men with high waking T were more likely to become partnered fathers by the time of follow-up 4.5 y later (P< 0.05). Men who became partnered fathers then experienced large declines in waking (median: −26%) and evening (median: −34%) T, which were significantly greater than declines in single nonfathers (P < 0.001). [why did they use single nonfathers as control?] Consistent with the hypothesis that child interaction suppresses T, fathers reporting 3 h or more of daily childcare had lower T at follow-up compared with fathers not involved in care (P < 0.05). Using longitudinal data, these findings show that T and reproductive strategy have bidirectional relationships in human males, with high T predicting subsequent mating success but then declining rapidly after men become fathers. Our findings suggest that T mediates tradeoffs between mating and parenting in humans, as seen in other species in which fathers care for young. They also highlight one likely explanation for previously observed health disparities between partnered fathers and single men.

Constrained mate choice in social monogamy and the stress of having an unattractive partner

Constrained mate choice in social monogamy and the stress of having an unattractive partner
Simon C Griffith at al.; 2011
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3145185/


Abstract

In socially monogamous animals, mate choice is constrained by the availability of unpaired individuals in the local population. Here, we experimentally investigate the physiological stress endured by a female (the choosy sex) when pairing with a non-preferred social partner. In two experimental contexts, female Gouldian finches (Erythrura gouldiae) socially paired with poor-quality mates had levels of circulating corticosterone that were three to four times higher than those observed in females that were paired with preferred mates. The elevated level of this stress hormone in response to partner quality was observed within 12 h of the experimental introduction and maintained over a period of several weeks. Our findings demonstrate the extent of intra-individual conflict that occurs when individuals are forced to make mate-choice decisions that are not perfectly aligned with mate-choice preferences. The elevated level of corticosterone also suggests a mechanistic route through which females might adaptively manage their responses to intersexual conflict over reproductive investment.

Mittwoch, 24. April 2013

Systematic cognitive biases in courtship context: women's commitment–skepticism as a life-history strategy?

Systematic cognitive biases in courtship context: women's commitment–skepticism as a life-history strategy?
Kerstin Cyrus et al.; 2011


Abstract

According to error management theory (EMT) [Haselton M.G., & Buss D.M. (2000). Error management theory: a new perspective on biases in cross-sex mind reading. Journal of Personality and Social Psychology, 78, 81–91], evolved psychological mechanisms can lead to systematic cognitive errors whenever costs of false-positive and false-negative decisions have been asymmetrical over evolutionary history. In a courtship context, sex differences in reading commitment intent in a potential partner seem to be a result of these psychological mechanisms. EMT predicts a bias in women toward underperception of men's commitment intentions. Haselton and Buss found evidence for a commitment–skepticism bias in studies testing young women. These findings have not been replicated yet in the published literature. The present two studies compared postmenopausal women with fertile women in a German sample, extending EMT with a life-history perspective. According to the original commitment–skepticism hypothesis, women err on the side of underestimating prospective mates' commitment to avoid the high costs of pregnancy without support. We hypothesize that for postmenopausal women the costs of errors would be more equal or possibly reversed, such that these women face greater costs of missed opportunities with investing partners who could assist them in caring for extant offspring and grand offspring than from falsely assuming that a partner was committed. Therefore, we hypothesize that commitment–skepticism will not occur in postmenopausal women. Confirming our predictions, whereas we replicated the commitment–skepticism in the younger sample, postmenopausal women did not show a bias toward underinferring men's commitment intentions.

Hormonal birth control use and relationship jealousy: Evidence for estrogen dosage effects

Hormonal birth control use and relationship jealousy: Evidence for estrogen dosage effects
Kelly D Cobey et al.; 2011
http://pcwww.liv.ac.uk/~scr/pdf/2010_Cobey%20PAID.pdf


Abstract

Women who use hormonal contraceptives have been shown to report higher levels of jealousy than women who are regularly cycling. Here, we extend these findings by examining if self reported levels of jealousy vary with the dose of synthetic estrogen and progestin found in combined oral contraceptives in a sample of 275 women. A univariate ANOVA analysis revealed that higher levels of ethinyl estradiol were associated with significantly higher levels of self-reported jealousy. There was, however, no relationship between combined oral contraceptive progestin dose and reported jealousy levels. When controlling for age, relationship status, mood, and combined oral contraceptive progestin dose the results for ethinyl estradiol were maintained. A test for the interaction between the jealousy sub-scale items (reactive, possessive, and anxious jealousy) was however non-significant: ethinyl estradiol dose thus does not affect one type of jealousy more than another but rather affects overall jealousy. The implications of these findings are discussed in the context of their evolutionary consequences on mate choice and relationship dynamics.


Sex differences and sex similarities in disgust sensitivity

Sex differences and sex similarities in disgust sensitivity
Joshua M Tybur et al.; 2011
http://www.unm.edu/~anncwell/Welcome_files/Tybur%20et%20al_PAID%202011.pdf


Abstract

Across two studies, we test for sex differences in the factor structure, factor loadings, concurrent validity, and means of the Three Domain Disgust Scale. In Study 1, we find that the Three Domain Disgust Scale has indistinguishable factor structure and factor loadings for men and women. In Study 2, we find a small sex difference in sensitivity to pathogen and moral disgust and a large sex difference in sensitivity to sexual disgust, with women more sensitive to disgust across domains. However, correlations between Three Domain Disgust Scale factors and the five factors and 30 facets of the NEO Personality Inventory were indistinguishable between the sexes. These findings suggest that, despite mean sex differences in disgust sensitivity, the Three Domain Disgust Scale measures similar constructs in men and women. Implications for understanding the constructs measured by the Three Domain Disgust Scale are discussed.


Dienstag, 23. April 2013

Muscularity and attractiveness as predictors of human egalitarianism

Muscularity and attractiveness as predictors of human egalitarianism
Michael E Price et al.; 2011
http://people.brunel.ac.uk/~hsstmep/Price_et_al_2011_PAID.pdf


Abstract

In ancestral human environments, muscularity and height (in males) and physical attractiveness (in both sexes) would theoretically have correlated positively with one’s social status, and thus with one’s ability to benefit from social inequality. We therefore hypothesized that individuals who are more characterized by these traits would be less egalitarian (i.e., less likely to believe that resources should be distributed equally in social groups). We used a white-light 3D body scanner to extract anthropometric measurements from 118 participants, and our four egalitarianism measures included social dominance orientation and social value orientation. We found that as hypothesized, muscularity and waist–chest ratio in males, and self-perceived attractiveness in both sexes, tended to associate significantly in the predicted directions with the four egalitarianism measures; most of these correlations were of medium size. Neither height, nor two anthropometrically-assessed attractiveness measures (volume height index and waist–hip ratio), associated significantly with any egalitarianism measure in either sex. Egalitarianism has crucial social repercussions (e.g., taxes, welfare and civil rights), and results from the current study shed light on its origins.

Kin recognition: evidence that humans can perceive both positive and negative relatedness

Kin recognition: evidence that humans can perceive both positive and negative relatedness
D B Krupp et al.; 2012
http://www.mast.queensu.ca/~dbkrupp/papers/krupp_etal_jeb.pdf


Abstract

The evolution of spite entails actors imposing costs on ‘negative’ relatives: those who are less likely than chance to share the actor’s alleles and therefore more likely to bear rival alleles. Yet, despite a considerable body of research confirming that organisms can recognize positive relatives, little research has shown that organisms can recognize negative relatives. Here, we extend previous work on human phenotype matching by introducing a cue to negative relatedness: negative self-resembling faces, which differ from an average face in the opposite direction to the way an individual’s own face differs from the average. Participants made trustworthiness and attractiveness judgements of pairs of opposite-sex positive and negative self-resembling faces. Analyses revealed opposing effects of positive and negative self-resembling faces on trustworthiness and attractiveness judgements. This is the first clear  evidence that humans are sensitive to negative relatedness cues, and suggests the potential for the adaptive allocation of spiteful behaviour.

Cues to Personality and Health in the Facial Appearance of Chimpanzees

Cues to Personality and Health in the Facial Appearance of Chimpanzees
Robin S S Kramer & Robert Ward
http://kar.kent.ac.uk/33327/1/Kramer%20%26%20Ward%202012.pdf


Abstract

Humans (Homo sapiens) and chimpanzees (Pan troglodytes) can extract socially-relevant information from the static, non-expressive faces of conspecifics. In humans, the face is a valid signal of both personality and health. Recent evidence shows that, like humans, chimpanzee faces also contain personality information, and that humans can accurately judge aspects of chimpanzee personality relating to extraversion from the face alone (Kramer, King, and Ward, 2011). These findings suggest the hypothesis that humans and chimpanzees share a system of personality and facial morphology for signaling socially-relevant traits from the face. We sought to test this hypothesis using a new group of chimpanzees. In two studies, we found that chimpanzee faces contained health information, as well as information of characteristics relating to extraversion, emotional stability, and agreeableness, using average judgments from pairs of individual photographs. In a third study, information relating to extraversion and health was also present in composite images of individual chimpanzees. We therefore replicate and extend previous findings using a new group of chimpanzees and demonstrate two methods for minimizing the variability associated with individual photographs. Our findings support the hypothesis that chimpanzees and humans share a personality signaling system.

Female Facial Appearance and Health

Female Facial Appearance and Health
Alan W. Gray & Lynda G. Boothroyd; 2012
http://dro.dur.ac.uk/9374/1/9374.pdf


Abstract

The current study addressed whether rated femininity, attractiveness, and health in female faces are associated with numerous indices of self-reported health history (number of colds/stomach bugs/frequency of antibiotic use) in a sample of 105 females. It was predicted that all three rating variables would correlate negatively with bouts of illness (with the exception of rates of stomach infections), on the assumption that aspects of facial appearance signal mate quality. The results showed partial support for this prediction, in that there was a general trend for both facial femininity and attractiveness to correlate negatively with the reported number of colds in the preceding twelve months and with the frequency of antibiotic use in the last three years and the last twelve months. Rated facial femininity (as documented in September) was also associated with days of flu experienced in the period spanning the November-December months. However, rated health did not correlate with any of the health indices (albeit one marginal result with antibiotic use in the last twelve months). The results lend support to previous findings linking facial femininity to health and suggest that facial femininity may be linked to some aspects of disease resistance but not others.


[Mr. Mangan made an interesting comment on this article: Beauty isn't skin deep]

Evolved sex differences and occupational segregation

Evolved sex differences and occupational segregation
Kingsley R Browne; 2006
http://faculty.law.wayne.edu/browne/Documents/Articles/Evolved%20Sex%20Differences%20and%20Occupational%20Segregation_Browne.pdf


Abstract

Average sex differences in workplace outcomes are often assumed to be products of a malfunctioning labor market that discourages women from nontraditional occupations and a biased educational system that leaves women inadequately prepared for scientific and technical work. Rather than being a product purely of discriminatory demand, however, many sex differences in occupational distribution are at least partially a result of an imbalance in supply. Sex differences in both temperament and cognitive ability, which are products of our evolutionary history, predispose men and women toward different occupational behavior. The tendency of men to predominate in fields imposing high quantitative demands, high physical risk, and low social demands, and the tendency of women to be drawn to less quantitatively demanding fields, safer jobs, and jobs with a higher social content are, at least in part, artifacts of an evolutionary history that has left the human species with a sexually dimorphic mind. These differences are proximately mediated by sex hormones.

Montag, 22. April 2013

Biological sex differences in the workplace: Reports of the end of men are greatly exaggerated (as are claims of women’s continued inequality)

Biological sex differences in the workplace: Reports of the end of men are greatly exaggerated (as are claims of women’s continued inequality)
Kingsley R Browne; 2013
http://papers.ssrn.com/sol3/papers.cfm?abstract_id=2251447 (Link for full download)


Abstract

Common examples of perceived workplace inequality – the “glass ceiling,” the “gender gap” in compensation, and occupational segregation among others – cannot be well understood if the explanation proffered for their existence is limited exclusively to social causes such as discrimination and sexist socialization. Males and females have, on average, different sets of talents, tastes, and interests, which cause them to select somewhat different occupations and exhibit somewhat different workplace behaviors. Some of these sex differences have biological roots. Temperamental sex differences are found in competitiveness, dominance-seeking, risk-taking, and nurturance, with females tending to be more “person-oriented” and males more “thing-oriented.” The sexes also differ in a variety of cognitive traits, including various spatial, verbal, mathematical, and mechanical abilities. Although social influences can be important, these social influences operate on (and were in fact created by) sexually dimorphic minds.
Substantial changes in the environment of a complex organism will often result in changes in its behavior. Therefore, we should not be surprised when changes in the economy or changes in the nature of work are followed by changes in workforce behavior and, hence, changes in workplace outcomes. For those keeping track of “the numbers,” these changes may be characterized as either increasing or decreasing equality, depending upon the particular definition of equality selected. Moreover, whether one views a particular outcome as a harbinger of the “end of men” or a reflection of continued sexual inequality of women may be a consequence of whether the focus is on group averages or the tail end of distributions. It may turn out, for example, that even if women may do better as a group on some measures, men may still dominate at the top.

A post-genomic view of behavioral development and adaptation to the environment

A post-genomic view of behavioral development and adaptation to the environment
Peter LaFreniere and Kevin Mac Donald; 2013


Abstract

Recent advances in molecular genetics are reviewed that have major implications for the biobehavioral sciences and for understanding how organisms adapt to their environments at both phylogenetic and ontogenic levels. From a post-genomics perspective, the environment is as crucial as the DNA sequence for constructing the phenotype, and as a source of information in trying to predict phenotypes. The review is organized with respect to five basic processes by which phenotypes adapt to both recurrent and novel environmental challenges, with an emphasis on the data for humans: 1) developmental plasticity, 2) epigenetic mechanisms, 3) genotypeenvironment correlations, 4) gene x environment interactions, and 5) domain-general psychological mechanisms.

Oxytocin facilitates accurate perception of competition in men and kinship in women

Oxytocin facilitates accurate perception of competition in men and kinship in women
Meytal Fischer-Shofty et al.; 2013
Social Cognitive and Affective Neuroscience


Abstract

Despite the dominant role of the hormone oxytocin (OT) in social behavior, little is known about the role of OT in the perception of social relationships. Furthermore, it is unclear whether there are sex differences in the way that OT affects social perception. Here, we employed a double-blind, placebo-controlled crossover design to investigate the effect of OT on accurate social perception. Following treatment, 62 participants completed the Interpersonal Perception Task, a method of assessing the accuracy of social judgments that requires identification of the relationship between people interacting in real life video clips divided into three categories: kinship, intimacy and competition. The findings suggest that OT had a general effect on improving accurate perception of social interactions. Furthermore, we show that OT also involves sex-specific characteristics. An interaction between treatment, task category and sex indicated that OT had a selective effect on improving kinship recognition in women, but not in men, whereas men's performance was improved following OT only for competition recognition. It is concluded that the gender-specific findings reported here may point to some biosocial differences in the effect of OT which may be expressed in women's tendency for communal and familial social behavior as opposed to men's tendency for competitive social behavior.

Sonntag, 21. April 2013

Perceptions of Human Attractiveness Comprising Face and Voice Cues

Perceptions of Human Attractiveness Comprising Face and Voice Cues
Timothy Wells et al.; 2013


Abstract

In human mate choice, sexually dimorphic faces and voices comprise hormone-mediated cues that purportedly develop as an indicator of mate quality or the ability to compete with same-sex rivals. If preferences for faces communicate the same biologically relevant information as do voices, then ratings of these cues should correlate. Sixty participants (30 male and 30 female) rated a series of opposite-sex faces, voices, and faces together with voices for attractiveness in a repeated measures computer-based experiment. The effects of face and voice attractiveness on face-voice compound stimuli were analyzed using a multilevel model. Faces contributed proportionally more than voices to ratings of face-voice compound attractiveness. Faces and voices positively and independently contributed to the attractiveness of male compound stimuli although there was no significant correlation between their rated attractiveness. A positive interaction and correlation between attractiveness was shown for faces and voices in relation to the attractiveness of female compound stimuli. Rather than providing a better estimate of a single characteristic, male faces and voices may instead communicate independent information that, in turn, provides a female with a better assessment of overall mate quality. Conversely, female faces and voices together provide males with a more accurate assessment of a single dimension of mate quality.

‘Slow’ reproductive strategy: A negative predictor of depressive symptomatology

‘Slow’ reproductive strategy: A negative predictor of depressive symptomatology
Cezar Giosan; 2013
Australian Journal of Psychology


Abstract

The present study examined the associations between a high-K (slow) life history strategy and depressive symptomatology. The participants were a sample of 494 male utility workers who underwent psychological evaluations. It was hypothesised that high-K will correlate negatively with, and will be a negative predictor of, depressive symptomatology. The results confirmed the predictions, showing that high-K accounts for 15% of the variance in depressive symptomatology after controlling for risk factors for depression such as demographics, prior traumatic experiences, past depression, and recent negative life events. Implications of the results are discussed.

Mittwoch, 17. April 2013

Two Ways to the Top: Evidence That Dominance and Prestige Are Distinct Yet Viable Avenues to Social Rank and Influence

Two Ways to the Top: Evidence That Dominance and Prestige Are Distinct Yet Viable Avenues to Social Rank and Influence
Joey T. Cheng et al.; 2013
http://ubc-emotionlab.ca/wp-content/files_mf/chengetal.2013twowaystothetop.pdf


Abstract

The pursuit of social rank is a recurrent and pervasive challenge faced by individuals in all human societies. Yet, the precise means through which individuals compete for social standing remains unclear. In 2 studies, we investigated the impact of 2 fundamental strategies—Dominance (the use of force and intimidation to induce fear) and Prestige (the sharing of expertise or know-how to gain respect)— on the attainment of social rank, which we conceptualized as the acquisition of (a) perceived influence over others (Study 1), (b) actual influence over others’ behaviors (Study 1), and (c) others’ visual attention (Study 2). Study 1 examined the process of hierarchy formation among a group of previously unacquainted individuals, who provided round-robin judgments of each other after completing a group task. Results indicated that the adoption of either a Dominance or Prestige strategy promoted perceptions of greater influence, by both group members and outside observers, and higher levels of actual influence, based on a behavioral measure. These effects were not driven by popularity; in fact, those who adopted a Prestige strategy were viewed as likable, whereas those who adopted a Dominance strategy were not well liked. In Study 2, participants viewed brief video clips of group interactions from Study 1 while their gaze was monitored with an eye tracker. Dominant and Prestigious targets each received greater visual attention than targets low on either dimension. Together, these findings demonstrate that Dominance and Prestige are distinct yet viable strategies for ascending the social hierarchy, consistent with evolutionary theory.

Adaptive attentional attunement: evidence for mating-related perceptual bias

Adaptive attentional attunement: evidence for mating-related perceptual bias
Jon K Maner et al.; 2007
http://psych.mcmaster.ca/psyweb/3f3e/reading12.pdf


Abstract

Substantial evidence suggests that physical attractiveness plays an important role in shaping overt mating preferences, judgments, and choices. Relatively few studies, however, have investigated the hypothesis that perceivers are attuned to signs of attractiveness at early, lower-order stages of social perception. In the current research, a visual cueing task was used to assess biases in attentional disengagement—the extent to which people’s attention becomes stuck on particular social stimuli. Findings indicate that, consistent with some evolutionary theories, perceivers of both sexes exhibited attentional attunement to attractive women, but not attractive men. Additional findings suggest that this bias was pronounced in sexually unrestricted men and in women who felt insecure about a current romantic relationship. This research provides novel evidence for adaptive, lower-order perceptual attunements in the domain of human mating.

Dienstag, 16. April 2013

Evolution of Fatherhood

Evolution of Fatherhood (Family Relationships: An Evolutionary Perspective)
David C Geary; 2007
http://web.missouri.edu/~gearyd/files/Geary%20[2007%20Evo%20of%20Fatherhood%20proof].pdf

Conclusion:

>Cultural debates regarding men’s contributions to families and their children and the occasional rancor over the unequal contributions of men and women to parenting belie a deeper and rarely considered scientific riddle; specifically, on the basis of little or no male parenting in nearly all other mammalian species and among our two closest living relatives, it is a scientific curiosity that men invest in families and children at all. To understand how men’s parenting evolved and how it is maintained in the here and now, we must consider the factors related to the evolution and expression of male parenting across other species. These factors involve tradeoffs that balance the benefits of male protection and provisioning to the health and later competitiveness of his offspring, weighed against the risk of cuckoldry and the cost of lost mating opportunities. Of course, it is likely that male parenting would benefit offspring even in species where this parenting does not occur. However, in these species, males that compete for access to mates out-reproduce any parental fathers, and thus any tendency toward the latter does not evolve.
Men’s parenting is consistent with the same cost–benefit tradeoffs in other species in which paternal investment is found. In traditional and developing societies today and in the historical record, men’s investment in families substantively reduced children’s morality risks and improved their physical health and development. In these societies and in Western societies today, men’s investment often facilitates their children’s ability to acquire the skills needed to compete in adulthood. Children who become successful adults are able to better care for and thus lower the mortality risks and enhance the later competitiveness of men’s grandchildren. Men also benefit because of comparatively high levels of paternity certainty, although cuckoldry does occur and men and women show evidence of corresponding adaptations. Women’s reluctance to engage in casual sex greatly reduces men’s mating opportunities, and in so doing, lowers the opportunity cost of paternal investment.
Even with an evolved bias to invest in children, there is considerable variation among men as to when and with whom they will invest in a family. The influences on the expression of men’s parental behaviors are multifaceted and range from the genes that influence the expression of parentingrelated hormones to the quality of the marital relationships to cultural mores regarding marriage practices (e.g., whether or not polygyny is allowed). A comparative and evolutionary perspective on men’s parenting provides a broader perspective for understanding these patterns and allows us to more fully understand when, where, and with whom men will invest in families.<

Montag, 15. April 2013

Consequences of Age-Related Cognitive Declines

Consequences of Age-Related Cognitive Declines
Timothy Salthouse; 2011
http://faculty.virginia.edu/cogage/publications2/Salthouse%20(in%20press)%20Consequences%20of%20age-related%20cognitive%20declines.pdf


Abstract


Adult age differences in a variety of cognitive abilities are well documented, and many of those abilities have been found to be related to success in the workplace and in everyday life. However, increased age is seldom associated with lower levels of real-world functioning, and the reasons for this lab-life discrepancy are not well understood. This article briefly reviews research concerned with relations of age to cognition, relations of cognition to successful functioning outside the laboratory, and relations of age to measures of work performance and achievement. The final section discusses several possible explanations for why there are often little or no consequences of age-related cognitive declines in everyday functioning.

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"The preceding review indicates that with only a few exceptions, there is little evidence of a negative relation of age (at least within the range of 20 to 75 years of age) and indices of overall level of functioning in society. Assuming that the age-cognition and cognition-functioning relations reviewed above are valid estimates of the true population relations, the positive cognition-functioning relation and negative age-cognition relation lead to expectations of negative relations between age and functioning that are rarely observed."

Openness, Fluid Intelligence, and Crystallized Intelligence: Toward an Integrative Model

Openness, Fluid Intelligence, and Crystallized Intelligence: Toward an Integrative Model
M. Ziegler et al.; 2012
http://scottbarrykaufman.com/wp-content/uploads/2012/02/Ziegler-et-al.-2012.pdf


Abstract

Many studies are concerned with the bivariate relationships between Openness, fluid intelligence (Gf), and crystallized intelligence (Gc). Results suggest an influence of Gf and Openness on Gc. However, the overlap between Gf and Openness is rarely controlled for. Moreover, interaction effects or longitudinal influences are also often neglected. The present two studies aimed to elucidate exactly these interactions and longitudinal influences. Besides a main effect of Gf on Gc, Study 1 (N=180) revealed an interaction effect between Openness and Gf. Study 2 utilized longitudinal data (N=173) and identified an effect of Openness on the development of Gf. Gf and Openness predicted Gc 6 years later. A model integrating the results and providing a theoretical framework and outlook is proposed.

Donnerstag, 11. April 2013

Universal dimensions of social cognition: warmth and competence

Universal dimensions of social cognition: warmth and competence
Susan T Fiske et al.; 2007
http://www.relationalcapitalgroup.com/wp-content/uploads/2010/03/Warmth-Competence-2007.pdf


Abstract

Like all perception, social perception reflects evolutionary pressures. In encounters with conspecifics, social animals must determine, immediately, whether the ‘other’ is friend or foe (i.e. intends good or ill) and, then, whether the ‘other’ has the ability to enact those intentions. New data confirm these two universal dimensions of social cognition: warmth and competence. Promoting survival, these dimensions provide fundamental social structural answers about competition and status. People perceived as warm and competent elicit uniformly positive emotions and behavior, whereas those perceived as lacking warmth and competence elicit uniform negativity. People classified as high on one dimension and low on the other elicit predictable, ambivalent affective and behavioral reactions. These universal dimensions explain both interpersonal and intergroup social cognition.


"[People]  everywhere differentiate each other by liking (warmth, trustworthiness) and by respecting (competence, efficiency)."

"The basic dimensions of warmth and competence account for 82% of the variance in perceptions of everyday social behaviors ."

"In sum, when people spontaneously interpret behavior or form impressions of others, warmth and competence form basic dimensions that, together, account almost entirely for how people characterize others."

"Although warmth and competence dimensions emerge consistently, considerable evidence suggests that warmth judgments are primary: warmth is judged before competence, and warmth judgments carry more weight in affective and behavioral reactions."

"The priority for detecting warmth over competence, although robust, is stronger for some kinds of perceivers than others. In particular, women, whose traditional gender roles emphasize communal (warmth) over agentic (competence) traits, show a stronger priority for detecting warmth. Communal traits traditionally affect women’s lives more, whereas competence traits traditionally affect men relatively more."

Humor in Romantic Contexts: Do Men Participate and Women Evaluate?

Humor in Romantic Contexts: Do Men  Participate and Women Evaluate?
Cristopher J Wilbur and Lorne Campbell; 2011


Abstract

Several lines of research illustrate that humor plays a pivotal role in relationship initiation. The current article applies sexual selection theory to argue that humor production is a fitness indicator, allowing men to transmit information tacitly about their underlying qualities. And whereas prior research has emphasized women’s appreciation of humor as a signal of interest, the focus here is on how women evaluate prospective suitors’ humorous offerings. Two studies, including an ecologically valid study of online dating advertisements, provided evidence for men’s production and women’s evaluation of humor in romantic contexts. A third study revealed that women’s evaluations of potential mates’ humor are predictive of their romantic interest. Moreover, this article shows that preferences for and perceptions of humor are associated with preferences for and perceptions of intelligence and warmth, consistent with the argument that one function of humor is as a fitness indicator that provides information about underlying mate quality.


"Humor serves multiple purposes in human affairs, and our focus here is on the role of humor as a fitness indicator. As such, we argue that humor is not a valued trait in its own right; rather, it is valued in romantic partners to the extent that it honestly signals the presence of fundamentally important traits, such as intelligence and warmth."

Openness to Experience and Activity Engagement Facilitate the Maintenance of Verbal Ability in Older Adults

Openness to Experience and Activity Engagement Facilitate the Maintenance of Verbal Ability in Older Adults
Michael J Hogan et al.; 2012
http://scottbarrykaufman.com/wp-content/uploads/2013/01/Hogan-et-al.-2012.pdf



Abstract

The current study used data from the Aberdeen Birth Cohort, 1936, to investigate the hypothesis that the positive effects of the personality trait Openness on cognitive ability are mediated by activity levels. Results of latent growth modeling analysis revealed that higher Openness predicted better reading ability, inductive reasoning, and memory performance across three testing occasions when participants were aged 64 – 68 years. Higher Openness predicted higher activity levels, and higher activity levels in turn predicted higher reading ability, but not higher performance on measures of inductive reasoning, memory, and speed of processing. Overall, Openness and activity engagement appear related to preserved higher cognitive ability in older adults, with Openness having a direct effect on marker tests of fluid ability and with the combined influence of Openness and activity being particularly important for marker tests of crystallized intelligence.

Samstag, 6. April 2013

Are Old Adults Just Like Low Working Memory Young Adults? Filtering Efficiency and Age Differences in Visual Working Memory

Are Old Adults Just Like Low Working Memory Young Adults? Filtering Efficiency and Age Differences in Visual Working Memory
Kerstin Jost et al.; 2011
http://cercor.oxfordjournals.org/content/21/5/1147.full


Abstract

While it is well known that working memory functions decline with age, the functional reasons for this decline are not well understood. A factor that has proven critical for general individual differences in visual working memory capacity is the efficiency of filtering irrelevant information. Here, we examine to what degree this factor is also responsible for age differences in working memory. Young and old participants performed a change-detection task where some items in the encoding display were marked as irrelevant. The contralateral delay activity of the electroencephalogram was used to assess individual participants' filtering efficiency (see Vogel EK, McCollough AW, Machizawa MG. 2005. Neural measures reveal individual differences in controlling access to working memory. Nature. 438:500–503.). Older adults showed smaller filtering scores than young adults, but only early in the retention interval, suggesting that efficient filtering was delayed. In contrast, age-independent individual differences in filtering were reflected primarily later in the retention interval. Thus, age and individual differences in filtering are reflected in different ways showing that old adults are not simply like less efficiently performing young adults.

Heritability of Preferences for Multiple Cues of Mate Quality in Humans

Heritability of Preferences for Multiple Cues of Mate Quality in Humans
Brendan P Zietsch et al.; 2012
http://www.twinsuk.ac.uk/wp-content/uploads/2012/09/Zietsch-Evolution-2012-.pdf


Abstract

Human mate preferences have received a great deal of attention in recent decades because of their centrality to sexual selection, which is thought to play a substantial role in human evolution. Most of this attention has been on universal aspects of mate preferences, but variation between individuals is less understood. In particular, the relative contribution of genetic and environmental influences to variation in mate preferences is key to sexual selection models but has barely been investigated in humans, and results have been mixed in other species. Here, we used data from over 4000 mostly female twins who ranked the importance of 13 key traits in a potential partner. We used the classical twin design to partition variation in these preferences into that due to genes, family environment, and residual factors. In women, there was significant variability in the broad-sense heritability of individual trait preferences, with physical attractiveness the most heritable (29%) and housekeeping ability the least (5%). Over all the trait preferences combined, broad-sense heritabilities were highly significant in women and marginally significant in men, accounting for 20% and 19% of the variation, respectively; family environmental influences were much smaller. Heritability was a little higher in reproductive aged than in nonreproductive aged women, but the difference was not significant.

Freitag, 5. April 2013

Variety is the spice of life: A psychological construction approach to understanding variability in emotion

Variety is the spice of life: A psychological construction approach to understanding variability in emotion
Lisa Feldman Barrett; 2010
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2835153/


Abstract

There is remarkable variety in emotional life. Not all mental states referred to by the same word (e.g., “fear”) look alike, feel alike, or have the same neurophysiological signature. Variability has been observed within individuals over time, across individuals from the same culture, and of course across cultures. In this paper, I outline an approach to understanding the richness and diversity of emotional life. This model, called the conceptual act model, is not only well suited to explaining individual differences in the frequency and quality of emotion, but it also suggests the counter-intuitive view that the variety in emotional life extends past the boundaries of events that are conventionally called “emotion” to other classes of psychological events that people call by different names, such as “cognitions”. As a result, the conceptual act model is a unifying account of the broad variety of mental states that constitute the human mind.

Billionaires for open borders:

http://mangans.blogspot.co.at/2013/04/billionaires-for-open-borders.html

Global Connectivity of Prefrontal Cortex Predicts Cognitive Control and Intelligence

Global Connectivity of Prefrontal Cortex Predicts Cognitive Control and Intelligence
Michael W Cole et al.; 2010
http://www.jneurosci.org/content/32/26/8988.full


Abstract

Control of thought and behavior is fundamental to human intelligence. Evidence suggests a frontoparietal brain network implements such cognitive control across diverse contexts. We identify a mechanism—global connectivity—by which components of this network might coordinate control of other networks. A lateral prefrontal cortex (LPFC) region's activity was found to predict performance in a high control demand working memory task and also to exhibit high global connectivity. Critically, global connectivity in this LPFC region, involving connections both within and outside the frontoparietal network, showed a highly selective relationship with individual differences in fluid intelligence. These findings suggest LPFC is a global hub with a brainwide influence that facilitates the ability to implement control processes central to human intelligence.

Cognitive Capitalism:

Cognitive Capitalism: The Effect of  Cognitive Ability on Wealth, as Mediated  Through Scientific Achievement and  Economic Freedom
Heiner Rindermann and James Thompson; 2011
https://lesacreduprintemps19.files.wordpress.com/2011/05/rindermann-and-thompson-2011-cognitive-capitalism.pdf


Abstract

Traditional economic theories stress the relevance of political, institutional, geographic, and historical factors for economic growth. In contrast, human-capital theories suggest that peoples’ competences, mediated by technological progress, are the deciding factor in a nation’s wealth. Using three large-scale assessments, we calculated cognitive-competence sums for the mean and for upper- and lower-level groups for 90 countries and compared the influence of each group’s intellectual ability on gross
domestic product. In our cross-national analyses, we applied different statistical methods (path analyses, bootstrapping) and measures developed by different research groups to various country samples and historical periods. Our results underscore the decisive relevance of cognitive ability—particularly of an intellectual class with high cognitive ability and accomplishments in science, technology, engineering, and math—for national wealth. Furthermore, this group’s cognitive ability predicts the quality of economic and political institutions, which further determines the economic affluence of the nation. Cognitive resources enable the evolution of capitalism and the rise of wealth.

Mittwoch, 3. April 2013

Religiosity and fear of death: a three‐nation comparison

Religiosity and fear of death: a three‐nation comparison
Lee Ellis et al.; 2013


Abstract

Numerous studies have sought to determine if religiosity is correlated with fear of death. Findings have been anything but consistent, with reports of negative relationships, positive relationships, no relationship, and even curvilinear associations. To shed light on this still contentious issue, the present study was undertaken among college students in three countries – Malaysia, Turkey, and the United States. Overall, the patterns in all three countries were similar. When linearity was assumed, there is a substantial positive correlation between most religiosity measures and fear of death. Assuming curvilinearity added slightly to the strength of the relationships in the US data and nothing to data from Malaysia or Turkey. Other findings were that on average females were more religious and feared death more than did males, and Muslims expressed considerably greater fear than did members of any other major religion. Results were discussed in the context of a new theory – called death apprehension theory. Among other things, it specifically predicts that death apprehension will be positively related to most religious beliefs and practices.

Bottom-up and top-down emotion generation: implications for emotion regulation

Bottom-up and top-down emotion generation: implications for emotion regulation
Kateri Mc Rae et al., 2012
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3304475/


Abstract

Emotion regulation plays a crucial role in adaptive functioning and mounting evidence suggests that some emotion regulation strategies are often more effective than others. However, little attention has been paid to the different ways emotions can be generated: from the ‘bottom-up’ (in response to inherently emotional perceptual properties of the stimulus) or ‘top-down’ (in response to cognitive evaluations). Based on a process priming principle, we hypothesized that mode of emotion generation would interact with subsequent emotion regulation. Specifically, we predicted that top-down emotions would be more successfully regulated by a top-down regulation strategy than bottom-up emotions. To test this hypothesis, we induced bottom-up and top-down emotions, and asked participants to decrease the negative impact of these emotions using cognitive reappraisal. We observed the predicted interaction between generation and regulation in two measures of emotional responding. As measured by self-reported affect, cognitive reappraisal was more successful on top-down generated emotions than bottom-up generated emotions. Neurally, reappraisal of bottom-up generated emotions resulted in a paradoxical increase of amygdala activity. This interaction between mode of emotion generation and subsequent regulation should be taken into account when comparing of the efficacy of different types of emotion regulation, as well as when reappraisal is used to treat different types of clinical disorders.

The Motivation to Control and the Origin of Mind:

The Motivation to Control and the Origin of Mind: Exploring the Life–Mind Joint Point in the Tree of Knowledge System
David C Geary; 2005
http://web.missouri.edu/gearyd/JCP05%5Bfinal%5D05.pdf


Abstract

The evolved function of brain, cognitive, affective, conscious-psychological, and behavioral systems is to enable animals to attempt to gain control of the social (e.g., mates), biological (e.g., prey), and physical (e.g., nesting spots) resources that have tended to covary with survival and reproductive outcomes during the species’ evolutionary history. These resources generate information patterns that range from invariant to variant. Invariant information is consistent across generations and within lifetimes (e.g., the prototypical shape of a human face) and is associated with modular brain and cognitive systems that coalesce around the domains of folk psychology, folk biology, and folk physics. The processing of information in these domains is implicit and results in automatic bottom-up behavioral responses. Variant information varies across generations and within lifetimes (e.g., as in social dynamics) and is associated with plastic brain and cognitive systems and explicit, consciously driven top-down behavioral responses. The fundamentals of this motivation-to-control model are outlined and links are made to Henriques’ (2004) Tree of Knowledge System and Behavioral Investment Theory.

The Influence of Male Voice Pitch on Women's Perceptions of Relationship Investment

The Influence of Male Voice Pitch on Women's Perceptions of Relationship Investment
J J M O' Connor, P J Fraccaro and D R Feinberg; 2012
http://voiceresearch.org/pdf/o'connor%20fraccaro%20and%20feinberg%202012.pdf


Abstract

The degree to which men invest financial resources, time, and effort into pursuing and maintaining relationships may be perceived by women as a cue to that man’s suitability as father and a mate. Women’s mate preferences are also influenced by cues to underlying heritable mate quality, such as an attractive, masculine voice. Relatively more masculine men may be able to provide heritable benefits to offspring, but masculinity is associated with decreased investment in relationships and offspring. Both individual differences in women’s preferences for masculine voices and women’s attributions of negative personality traits to masculine men suggests that women may be somewhat aware of the negative associations between men’s physical masculinity and relationship/parental investment. In the current study, we found that in general, women perceived feminized men’s voices as significantly more likely to invest time and effort, and be financially generous with romantic partners. We also found that women’s preferences for masculine voice pitch in a long-term, but not short-term relationship context, were positively related to perceptions of male financial generosity and investment of time and effort in romantic relationships. These perceptions may represent an adaptive heuristic that aids women in selecting long-term mates that are likely to invest in relationships and offspring.


Against Biology

http://westhunt.wordpress.com/2013/04/02/against-biology/

Dienstag, 2. April 2013

A mind of her own - 2nd edition:

I think the first version of "A mind of her own - the evolutionary psychology of women" (Anne Campbell, edited 2002) was a good read. In about one month a second, updated edition will come out. I will post a short review on my blog.