Monday, July 30, 2012

Semen an antidepressant? Alternative explanations appear more plausible.

A decade ago a study made an extraordinarily bold claim: that semen has antidepressant properties in women (Gallup, Burch, & Platek, 2002). Although widely-reported, there seems to have been a lack of critical response to this study (although see The Straight Dope and this article for exceptions) and apparently no follow up studies have been done to test whether this claim is actually valid.[1] The study was correlational in nature and provided no direct biological evidence for the claim that semen has an antidepressant effect. A well-known research principle is that correlation does not imply causation, and there are plausible alternative explanations that the authors of the study did not take into consideration.
Could condom use be depressing for women? Or are depressed women more likely to use them?

What the study actually found was that women who did not use condoms during sex had lower levels of depressive symptoms compared to women who usually or always used them, and to women who abstained from sex altogether. The authors argued that vaginal exposure to semen was the causal mechanism underlying this effect, arguing that semen has components including various hormones, particularly prostaglandins, that are readily absorbed into the woman’s bloodstream and that these have an antidepressant effect. The authors’ source for the antidepressant hypothesis was a single case study (Ney, 1986) which found that evening primrose oil apparently alleviated depression in a child-abusing mother. Ney argued that evening primrose oil and semen have in common the fact that they contain prostaglandins, and claimed that the latter have an antidepressant effect. Ney even went so far as to argue that in this particular case disruption to the woman’s sex life ensuing from the birth of her child was a causative factor in her depression because of the resulting lack of exposure to her husband’s semen. A single case study seems like a pretty tenuous basis for proposing such a far-fetched hypothesis but the story becomes even stranger. Ney admitted that semen contains fairly minute quantities of prostaglandins but argued that even so “they have powerful direct effects”, presumably effects on mood if this theory is to make sense. His authority for this was a review of the psychiatric implications of prostaglandins (Gross et al., 1977). What seems truly bizarre to me is that Gross et al. reported that from the little research that had been done on the subject, one study found that depressed patients had slightly elevated levels of prostaglandins, whereas another study found depressed patients had normal levels of prostaglandins (p. 1195). Furthermore, Gross et al. noted that antidepressant medications had an inhibitory effect on prostaglandins, although they stated that whether or not this had any clinical implications was as yet unknown (p. 1194). Surely, if absorption of prostaglandins in semen had an antidepressant effect, one would reasonably expect this to mean that depressed patients had low levels of these hormones or that antidepressant medications would actually increase not decrease their production, yet neither of these things appear to be true. Hence the claim that semen has any antidepressant properties at all does not appear to rest on any biological evidence.
Returning to Gallup et al.’s (2002) findings, not only have they provided no evidence that their finding that women who do not use condoms were less depressed than condom users was due to semen exposure, they did not properly consider a range of alternative explanations. For example they did not adequately explore why some women choose not to use condoms in the first place and whether pre-existing differences between users and non-users might have affected their results. Their results suggest some intriguing possibilities. They noted that non-users had the highest frequency of intercourse and in fact those who never used condoms had sex almost twice as frequently as those who always used condoms. However, when statistically controlling for condom use, frequency of intercourse did not predict depressive symptoms. Nevertheless, the fact that non users were not only less depressed but also had the most frequent intercourse suggests that non-users may be different from users in some important way. Gallup et al. argued that the important difference is their exposure to semen but since this was a correlational study they are not justified in arguing that this is the underlying cause of the relationship between condom use and depression, particularly when there are other plausible causal factors. Subsequent research has found that frequency of intercourse is positively correlated with both satisfaction with mental health and satisfaction with life in general (Brody & Costa, 2009) but this would not explain why condom use would seem to be related to depression. Brody (2010) has argued that sex with condoms is not real intercourse but something ‘akin to mutual masturbation’. I confess to finding this statement rather baffling but it is possible that for some women at least, sex with a condom may be less satisfying than without. One survey found that 40% of women reported decreased sensation associated with condom use and that some women associate condoms with a number of ‘turn-offs’ such as discomfort (Crosby, Milhausen, Yarber, Sanders, & Graham, 2008). Therefore, it seems possible that sexual enjoyment has an antidepressant effect that may be reduced by condom usage.
Another possibility, although it may sound strange, is that it is depression itself that leads to condom usage. Evidence for this comes from a study examining safe sex practices over a three month period (Morrill, Ickovics, Golubchikov, Beren, & Rodin, 1996). In this study, women who were depressed when the study began or who became depressed later on were more likely to use condoms. The authors noted that the association between depression and safer sex was influenced by the inclusion of women who were not sexually active. They suggested that depression may inhibit sexual activity. Even in a study like this, it is still difficult to untangle causality, as it is not clear why the women were initially depressed and whether or not their depression was somehow caused by their sexual behaviour or by something unrelated.
The possibility that depression may precede condom usage rather than being a result also suggests the possibility that personality characteristics that influence a woman’s decision whether or not to use a condom may also play a role in depression. Gallup et al. claimed that sexual risk-taking is unrelated to depression, but their two references supporting this statement were a study on homosexual men and one on drug users receiving psychiatric treatment. Considering the special nature of these two population groups it seems fair to say that they are not representative of the women in their study. It is possible that women who choose not to use condoms might have “happy-go-lucky” personalities compared to their more cautious counterparts, or perhaps some other combination of personality traits that protects them from depression. A Portuguese study found that women who use condoms are more likely to have “immature psychological defense mechanisms” than women who do not use them (Costa & Brody, 2008). These immature defense mechanisms are apparently associated with poorer mental health and more depression and anxiety. An earlier study found that socially anxious women were also more likely to use condoms compared to less anxious women and have less frequent sex (Leary & Dobbins, 1983). This seems comparable to Gallup et al.’s results who found condom using women were not only more depressed but had less frequent sex.
In conclusion, the claim by Gallup et al. that semen has an antidepressant effect is not only lacking any direct evidence, there does not even appear to be any plausible biological reason to believe that the components of semen have a beneficial effect on mood. The authors acknowledged that more definitive and direct evidence is needed, e.g. manipulation of the presence of semen[2] or measures of seminal components in the bloodstream. However, no studies providing such evidence appear to have been done and it may be there is little justification for investigating such a far-fetched hypothesis. There are plausible psychological mechanisms that could explain the relationship between condom use and depression, such as pre-existing depression, personality differences, or “turn-offs” associated with condom usage, that have not been adequately explored and seem more likely to yield informative results.

NB: Nothing in this post should be construed as advocating for or against condom usage. This is purely a discussion of scientific issues.


[1] Gallup et al. claim to have replicated their results with a larger sample, but their results have not as yet been published in a peer-review journal.
[2] I would imagine that trying to get such an experiment passed by an Ethics Committee would be far from easy!

Follow me on Facebook, Google Plus, or Twitter.

© Scott McGreal. Please do not reproduce without permission. Brief excerpts may be quoted as long as a link to the original article is provided. 

This article also appears on Psychology Today on my blog Unique - Like Everybody Else. 

Brody, S. (2010). The Relative Health Benefits of Different Sexual Activities. The Journal of Sexual Medicine, 7(4pt1), 1336-1361. doi: 10.1111/j.1743-6109.2009.01677.x
Brody, S., & Costa, R. M. (2009). Satisfaction (Sexual, Life, Relationship, and Mental Health) Is Associated Directly with Penile–Vaginal Intercourse, but Inversely with Other Sexual Behavior Frequencies. The Journal of Sexual Medicine, 6(7), 1947-1954. doi: 10.1111/j.1743-6109.2009.01303.x
Costa RM, & Brody S (2008). Condom use for penile-vaginal intercourse is associated with immature psychological defense mechanisms. The journal of sexual medicine, 5 (11), 2522-32 PMID: 18761591
Crosby, R., Milhausen, R., Yarber, W. L., Sanders, S. A., & Graham, C. A. (2008). Condom ‘turn offs’ among adults: an exploratory study. International Journal of STD & AIDS, 19(9), 590-594. doi: 10.1258/ijsa.2008.008120
Gallup GG Jr, Burch RL, & Platek SM (2002). Does semen have antidepressant properties? Archives of sexual behavior, 31 (3), 289-93 PMID: 12049024
Gross HA, Dunner DL, Lafleur D, Meltzer HL, Muhlbauer HL, & Fieve RR (1977). Prostaglandins. A review of neurophysiology and psychiatric implications. Archives of general psychiatry, 34 (10), 1189-96 PMID: 20867
Leary, Mark R., and Dobbins, Sharon E. Social Anxiety, Sexual Behavior, and Contraceptive Use. Journal of Personality and Social Psychology 45 (1983): 1347-54.
Morrill, A. C., Ickovics, J. R., Golubchikov, V. V., Beren, S. E., & Rodin, J. (1996). Safer Sex: Social and Psychological Predictors of Behavioral Maintenance and Change Among Heterosexual Women. Journal of Consulting and Clinical Psychology, 64(4), 819-828. doi: 10.1037/0022-006X.64.4.819
Ney PG (1986). The intravaginal absorption of male generated hormones and their possible effect on female behaviour. Medical hypotheses, 20 (2), 221-31 PMID: 3637620

Friday, July 27, 2012

Assessing “emotional intelligence” will not help us understand psychopathy

Psychopathy is a well-known personality disorder characterised by callousness, shallow emotions, and willingness to manipulate other people for selfish ends (Hare, 1999). Emotional deficits seem to be a core feature of psychopathy. For example, there is evidence that psychopaths lack normal response differentiation to emotional and neutral words, and may have impaired recognition of emotional faces, although the evidence is not completely consistent (Ermer, Kahn, Salovey, & Kiehl, 2012). Some researchers have used tests of “emotional intelligence” (EI)  in order to better understand emotional deficits in psychopathy, with somewhat mixed results (Lishner, Swim, Hong, & Vitacco, 2011). I would argue that emotional intelligence tests are unlikely to reveal much of importance about emotional deficits in psychopathy because they lack validity and have little relevance to psychopathy.
Extravagant claims that emotional intelligence is a more important predictor of success in life than IQ have not been borne out by empirical research.

Perhaps the most prominent test of emotional intelligence today is the Mayer–Salovey–Caruso Emotional Intelligence Test (MSCEIT), which purports to be an objective measure of one’s ability to perceive, understand, and manage emotions in self and others. The abilities it supposedly measures may be grouped into two areas: experiential EI (perceiving emotions and “facilitating thought”) and strategic EI (understanding and managing emotions). The perceiving emotions subtest is supposedly a strong indicator of empathic ability. Psychopaths are noted for their lack of empathic concern for others, yet a study of incarcerated men diagnosed with psychopathic traits found no correlation between experiential EI and psychopathy (Ermer, et al., 2012). The correlations between the perceiving emotion subscale and the psychopathy measures were all near zero. Psychopaths are supposed to be deficient in empathy yet they did not seem to be lacking ability to accurately perceive emotion in this study. This suggests either that the emotional perception measure is not a valid indicator of empathic ability or that in some sense psychopaths do not lack empathy. Perhaps psychopaths do perceive emotions accurately in others but the problem is that they are not moved by them. In other words, they know how others feel but simply do not care.
The same study did find rather small negative correlations between “strategic EI” and psychopathic traits, particularly in the “managing emotions” subtest. On its face, this might seem to suggest that psychopaths are not good at managing emotions in themselves or others. Or does it? According to psychopathy expert Robert Hare, psychopaths are highly motivated to manipulate others and are generally quick to get a read on people’s motivations and emotional vulnerabilities in order to exploit them (Hare, 1999). Some psychopathic individuals are noted for their use of superficial charm to successfully con other people into trusting them, suggesting that they do understand how to use people’s emotions, just not in a socially desirable manner. Social desirability might help explain why psychopaths apparently score badly on tests of managing emotions and what this really means.
The managing emotions subtest asks one to consider a scenario involving emotions in others and choose the “best” or “most effective” response (Ermer, et al., 2012). Scoring may be based on the general consensus method, which means that the “correct” response is the one that has been selected as best by the majority of people surveyed. There is also an “expert” scoring method, in which the correct response is the one most frequently endorsed by a panel of so-called “experts”. However, there is usually little difference between the two methods, suggesting that the experts agree with the majority of people. Hence, if you pick the answer that most people agree with you may be considered “emotionally intelligent”. This is in striking contrast to tests of general intelligence where highly intelligent people can produce answers that most people cannot (Brody, 2004).
In other words, the managing emotions subtest assesses endorsement of social norms. EI measures are designed to assess only socially acceptable uses of emotional information (Ermer, et al., 2012). Psychopaths on the other hand generally have little interest in following social norms, as psychopathic agendas such as conning and exploiting people are generally frowned upon. Therefore, their scores on emotional intelligence tests may reflect their lack of interest in following social norms rather than a lack of insight into what these norms are. The authors of another study on ability EI and psychopathy (Lishner, et al., 2011) acknowledged that participants had little incentive to produce the “correct” answers, so it was unclear whether the negative correlations they found between psychopathy and the managing emotions subtest reflected a real deficit or a lack of motivation to conform. EI tests have been criticised as a measure of conformity, so EI measures such as the MSCEIT may not be valid measures of ability because they assess conformity rather than competence. EI measures such as the managing emotions subtest assess knowledge, but do not assess actual skill in dealing with emotions (Brody, 2004). That is, a person may be aware of what they are supposed to do when dealing with an emotional person, but in practice they may or may not have the skill or ability to actually do it. Furthermore, whether a person uses their knowledge in daily life is not necessarily an issue of intelligence at all, as it may depend on habits, integrity and motivation (Locke, 2005).
Similarly in regard to psychopaths, the mere fact that they do not endorse the “correct” answers on EI tests does not mean they lack some form of “intelligence” required to understand emotions, because the test itself is not a measure of intelligence (Locke, 2005) but one of conformity to social norms. By definition, psychopaths disregard social norms, so the test does not seem to tell us anything we do not already know. Self-report measures of manipulation do exist, but it is not clear whether they measure actual ability to successfully manipulate other people’s emotions for personal gain (Ermer, et al., 2012). Understanding emotional deficits in psychopathy seems crucial to understanding this important and disturbing phenomenon but I would argue that the use of emotional intelligence tests is most likely a dead end because the measures are not valid and do not address the core emotional problems in the disorder. Psychopaths do seem to accurately perceive other people’s emotions but do not appear to have a normal emotional response themselves. Research focusing on why this is the case would seem to be a more productive avenue of enquiry.

Follow me on Facebook, Google Plus, or Twitter.

© Scott McGreal. Please do not reproduce without permission. Brief excerpts may be quoted as long as a link to the original article is provided. 

This article also appears on Psychology Today on my blog Unique - Like Everybody Else 

Other posts discussing intelligence related topics
Cold Winters and the Evolution of Intelligence: A critique of Richard Lynn’s Theory

The Illusory Theory of Multiple Intelligences – a critique of Howard Gardner’s theory

Brody, N. (2004). What Cognitive Intelligence Is and What Emotional Intelligence Is Not. Psychological Inquiry, 15(3), 234-238.
Ermer, E., Kahn, R. E., Salovey, P., & Kiehl, K. A. (2012). Emotional Intelligence in Incarcerated Men With Psychopathic Traits. Journal of Personality and Social Psychology : 10.1037/a0027328
Hare, R. (1999). Without conscience: The disturbing world of psychopaths among us. New York: The Guilford Press.
Lishner, D. A., Swim, E. R., Hong, P. Y., & Vitacco, M. J. (2011). Psychopathy and ability emotional intelligence: Widespread or limited association among facets? Personality and Individual Differences, 50 (7), 1029-1033 DOI: 10.1016/j.paid.2011.01.018
Locke, E. A. (2005). Why emotional intelligence is an invalid concept. Journal of Organizational Behavior. doi: 10.1002/job.318

Friday, July 20, 2012

Why are there sex differences in general knowledge?

A number of research studies have found that on average males score higher than females on tests of general knowledge (Lynn & Irwing, 2002; Lynn, Irwing, & Cammock, 2002). The reasons for this are not yet clear. Differences in verbal ability or abstract reasoning have been ruled out as explanations (Lynn & Irwing, 2002). Some researchers have argued that differences are most likely due to men and women having different interests. One study for example found that out of 19 domains of knowledge tested, males scored significantly higher on 12 domains, whereas women scored higher on two domains, medicine and cookery. Women are generally more interested in nurturing roles than men, so it makes sense that they would be more knowledgeable in these two areas. What is more puzzling though is that in other domains considered stereotypically feminine, there were either no gender differences (fashion and art), or men actually scored higher (literature). Previous research has found that women do tend to express more interest in artistic activities (Su, Rounds, & Armstrong, 2009) yet they did not have more knowledge of art than men. Males scored higher on domains related to current affairs, sports and games, and general science and biology. 

One explanation proposed for the male advantage in these domains, derived from evolutionary psychology, is that males are “biologically programmed” to be more concerned with competition for status and power, and these are central to such areas as current affairs (which includes politics and finance) and in sport and games. This seems all very well for those particular domains, especially politics, in which status and power concerns are very salient. However, “current affairs” in this study also encompassed the domains of history, geography, and exploration and discovery, and it is less clear how competition for status and power would lead to greater knowledge of these areas. Similarly, it is much less clear if this theory can explain why males would have greater knowledge of general science and biology or even the supposedly ‘feminine’ domain of literature. The authors admitted that gender differences in particular interests might be culturally determined but this still begs the question of why these differences occur, particularly in modern western societies where gender equality is increasingly emphasised.

Previous research has found that from an early age boys tend to show more interest in things, whereas girls show a greater interest in people (Su, et al., 2009). SimonBaron-Cohen (2003) has proposed that due to differences in the organisation of the brain, males have a bias towards “systematising”, that is, understanding the principles behind how things work, whereas females have a bias towards “empathising”, that is, understanding how people think and feel in particular social situations. This model might help explain why males tend to acquire greater factual knowledge than females. Males might have a greater motivation to gain factual knowledge due to a desire to understand how things in the world operate. Females might find this less appealing as they may be more motivated to learn about and understand people in their lives. As far as I know, there has not been any research examining whether gender differences in general knowledge are related to variation in systematising versus empathising.

Follow me on Facebook, Google Plus, or Twitter.
© Scott McGreal. Please do not reproduce without permission. Brief excerpts may be quoted as long as a link to the original article is provided.  

           This article also appears on Psychology Today on my blog Unique - Like Everybody Else.

Other posts discussing intelligence related topics
The Knowledgeable Personality - How general knowledge is related to Big Five personality traits 
Cold Winters and the Evolution of Intelligence: A critique of Richard Lynn’s Theory

The Illusory Theory of Multiple Intelligences – a critique of Howard Gardner’s theory

Baron-Cohen, S. (2003). The essential difference: men, women and the extreme
male brain. London: Penguin.
Lynn, R., & Irwing, P. (2002). Sex differences in general knowledge, semantic memory and reasoning ability British Journal of Psychology, 93 (4), 545-556 DOI: 10.1348/000712602761381394
Lynn, R., Irwing, P., & Cammock, T. (2002). Sex differences in general knowledge Intelligence, 30 (1), 27-39 DOI: 10.1016/S0160-2896(01)00064-2
Su, R., Rounds, J., & Armstrong, P. I. (2009). Men and Things, Women and People: A Meta-Analysis of Sex Differences in Interests. Psychological Bulletin, 135(6), 859–884. doi: 10.1037/a0017364

Wednesday, July 18, 2012

Psilocybin and personality

ResearchBlogging.orgSome recent research suggests interesting connections between the effects of the psychedelic drug psilocybin and personality traits. A review of studies on factors affecting response to psilocybin found that after dosage, the strongest predictor of alterations in consciousness was the personality trait of absorption (Studerus, Gamma, Kometer, & Vollenweider, 2012). Absorption is defined as a person’s tendency to have episodes of “total” attention where a person’s awareness is fully engaged in whatever has their interest. The degree to which people had “mystical” type experiences while on psilocybin was related to their individual proneness to absorption. Absorption is associated with the broader personality trait openness to experience, which relates to a person’s receptiveness to new ideas and experiences. 

What I found particularly interesting was that another study on psilocybin found that people who had never before taken the drug experienced an enduring increase in their level of openness to experience that was evident more than a year later (MacLean, Johnson, & Griffiths, 2011). In this study, people who experienced what the researchers described as a “complete mystical experience” developed increased openness to experience whereas those who did not have such an experience had no increase in this trait. Because absorption is closely related to openness to experience, this suggests that there may be a two-way relationship between openness and mystical experiences associated with psilocybin. That is, people who are more open to their inner experience seem more likely to have a mystical experience and those who have a mystical experience tend to become more open as a result. There is evidence that individual differences in absorption are associated with particular neurotransmitter receptors that are acted upon by psychedelic drugs such as psilocybin (Ott, Reuter, Hennig, & Vaitl, 2005), which might explain why absorption-prone people are more responsive to the drug’s effects. Since psilocybin can apparently cause increases in openness to experience in some people, it seems possible that the drug might permanently increase the sensitivity of these neuroreceptors resulting in associated personality change. This would need to be confirmed by research. 

Another intriguing research question concerns what effects increased openness to experience might have. Openness to experience is associated with creativity among other things, so it would be interesting to scientifically examine whether psilocybin use leads to long-term improvements in creativity or other aspects of behaviour associated with openness to experience. In the 1960s many popular musicians experimented with psychedelic drugs such as LSD and this apparently influenced their music. Unfortunately, research into these drugs was effectively banned around this time and only recently has there been a revival of scientific activity in this area. Such research could lead to some intriguing findings about the relationship between the brain, personality, and consciousness.  

Addendum: Research psychologist Sanjay Srivastana presents a thoughtful critique of the MacLean et al. study here. He recommended that the study be replicated with a control group to allow stronger inferences about the causal influence of psilocybin on openness to experience.

Other posts about psychedelic drugs and/or spirituality

Follow me on Facebook, Google Plus, or Twitter.
© Scott McGreal. Please do not reproduce without permission. Brief excerpts may be quoted as long as a link to the original article is provided.  

MacLean, K. A., Johnson, M. W., & Griffiths, R. R. (2011). Mystical Experiences Occasioned by the Hallucinogen Psilocybin Lead to Increases in the Personality Domain of Openness Journal of Psychopharmacology, 25 (11), 1453-1461 DOI: 10.1177/0269881111420188
Ott, U., Reuter, M., Hennig, J., & Vaitl, D. (2005). Evidence for a common biological basis of the absorption trait, hallucinogen effects, and positive symptoms: Epistasis between 5-HT2a and COMT polymorphisms. American Journal of Medical Genetics Part B: Neuropsychiatric Genetics, 137B(1), 29-32. doi: 10.1002/ajmg.b.30197
Studerus E, Gamma A, Kometer M, & Vollenweider FX (2012). Prediction of psilocybin response in healthy volunteers. PloS one, 7 (2) PMID: 22363492

Sunday, July 15, 2012

Conscientiousness, intelligence, and a pseudo-scientific hierarchy of humanness Researchers with an agenda based on "race realism" would have people believe that all the "socially desirable" characteristics that people can have are clustered together, and as a corollary all the unpleasant and antisocial traits cluster together too. More pointedly, the desirable traits are supposedly concentrated in certain racial groups, whereas the undesirable ones are characteristic of other races. According to a recently published paper (Templer, 2012) conscientiousness and intelligence apparently are positively correlated. The author states that: “The same conditions conducive to the evolution of greater intelligence would appear to be conducive to the evolution of greater conscientiousness.” The “same conditions” are assumed to involve challenges to survival. The author also links the development of intelligence to the development of a general factor of personality (GFP). The argument is that the GFP is associated with agreeable, altruistic, and conscientious behaviour that in turn helped foster greater cooperation leading to longer life spans and the development of larger brains. The author goes on to discuss Richard Lynn’s argument that dysgenic patterns of fertility are currently occurring in which highly intelligent people are having fewer children, while the less intelligent are having more. The author states that “Since intelligence is positively related to conscientiousness, such a fertility pattern is not one that generates optimism.” Incredibly, the author does not cite any evidence for this bizarre claim that higher intelligence is associated with higher conscientiousness. The only reason for making this claim appears to be the author's commitment to race realism and an associated "hierarchy of humanness".

A number of recently published studies have actually found that higher conscientiousness is associated with lower intelligence. There is even a paper called “Why is conscientiousness negatively correlated with intelligence?” published in an earlier issue of the same journal as Templer’s recent paper (Moutafi, Furnham, & Paltiel, 2004). Templer explicitly stated that conscientiousness is measured by the NEO-PI-R, the same personality trait measure used by Moutafi et al., so it cannot be the case that he is talking about a different construct with the same name. Templer equates low conscientiousness with psychopathic personality traits and then cites Lynn’s (2002) work on racial and ethnic differences in psychopathic traits as evidence for inter-racial differences in conscientiousness. Lynn’s study has been criticised as invalid for a host of reasons, such as confounding ‘psychopathy’ with antisocial personality disorder and citing purely behavioural data as evidence of psychopathy without consideration of environmental variables (Skeem, Edens, Sanford, & Colwell, 2003). Templer also links Lynn’s psychopathic characteristics to J. Philippe Rushton’s K differential theory, which theory has been criticised as scientifically invalid (Weizmann, Wiener, Wiesenthal, & Ziegler, 1991). Rushton’s theory argues that some human races are more ‘K-selected’ and hence more altruistic, whereas other are more ‘r-selected’ and hence more prone to criminality and psychopathy.

Rushton’s argument has been condemned not only for its unscientific basis but for promoting a “barely disguised hierarchy of humanness” in which “everything human and desirable is K and everything animalistic and evil is r” (Weizmann, et al., 1991). Perhaps this belief in a “hierarchy of humanness” can provide a clue as to why Templer would claim without any evidence at all that conscientiousness is positively correlated with intelligence. Templer supports Rushton’s theory of evolutionary selection for a ‘general factor of personality’ that combines all the socially desirable personality traits. Naturally, the general factor of personality is assumed to be ‘K-selected’ and not only that, it actually supported the development of greater intelligence in human evolution if the theory is to be believed. Therefore, Templer argues that some races have evolved not only larger brains and higher intelligence than others but this is because of their socially desirable traits, including greater conscientiousness. Therefore, it seems that Templer has just decided that conscientiousness and intelligence must be positively correlated because it fits into this hierarchy of humanness. A serious scientific problem with this hierarchy of humanness theory is that it appears to be built on a house of cards. Not only is the claim for a positive association between conscientiousness and intelligence contrary to evidence, nearly all the assumptions built into this hierarchical theory appear to be unfounded. For example, Muncer (2011) has argued that evolutionary theory does not support the existence of a general factor of personality. The environmental heterogeneity of environments during human evolutionary history supports a diversity of traits, because certain traits would be adaptive in some environments and not in others. Rushton’s theory on the other hand requires that a homogenous suite of personality traits ordered along a single dimension has been adaptive though all of human history, which would require a constant homogenous environment throughout this vast period. Weizmann et al. (1991) dissected Rushton’s theory in detail and showed how scientifically wanting it really is.

Presumably Templer believes high conscientiousness is important for the welfare of society. Since lower intelligence actually appears to be associated with higher conscientiousness, then perhaps these ‘dysgenic’ trends that worry Templer so, really are grounds for optimism. If people of lower intelligence are outbreeding the more intelligent, the result could be a generation of hard-working rule-abiding conscientious people rather than a society of psychopaths.

This article also appears on Psychology Today on my blog Unique - Like Everybody Else.

Follow me on Facebook, Google Plus, or Twitter.

© Scott McGreal. Please do not reproduce without permission. Brief excerpts may be quoted as long as a link to the original article is provided. 

Posts discussing the General factor of personality

Other posts discussing intelligence related topics
Cold Winters and the Evolution of Intelligence: A critique of Richard Lynn’s Theory
The Illusory Theory of Multiple Intelligences – a critique of Howard Gardner’s theory

Lynn, R. (2002). Racial and ethnic differences in psychopathic personality. Personality and Individual Differences, 32(2), 273-316. doi: 10.1016/s0191-8869(01)00029-0
Moutafi, J., Furnham, A., & Paltiel, L. (2004). Why is Conscientiousness negatively correlated with intelligence? Personality and Individual Differences, 37 (5), 1013-1022 DOI: 10.1016/j.paid.2003.11.010
Muncer, S. J. (2011). The general factor of personality: Evaluating the evidence from meta-analysis, confirmatory factor analysis and evolutionary theory. Personality and Individual Differences, 51(6), 775-778. doi: 10.1016/j.paid.2011.06.029
Skeem, J. L., Edens, J. F., Sanford, G. M., & Colwell, L. H. (2003). Psychopathic personality and racial/ethnic differences reconsidered: a reply to Lynn (2002). Personality and Individual Differences, 35(6), 1439-1462. doi: 10.1016/s0191-8869(02)00361-6
Templer, D. I. (2012). Richard Lynn and the evolution of conscientiousness Personality and Individual Differences, 53 (2), 94-98 DOI: 10.1016/j.paid.2011.05.023
Weizmann, F., Wiener, N. I., Wiesenthal, D. L., & Ziegler, M. (1991). Eggs, eggplants and eggheads: a rejoinder to Rushton. Canadian Psychology, 32 (1), 43-50 DOI: 10.1037/h0078958

Thursday, July 5, 2012

Wikipedians: are they really grumpy and close-minded?

A few years ago, New Scientist website published an article called “Psychologist finds Wikipedians grumpy and close-minded” that reported the findings of a study claiming that members of Wikipedia are lower than non-members in the personality traits of agreeableness and openness to experience. The claims in this article were widely repeated across the internet. The findings seemed surprising because agreeableness is usually associated with helping behaviour and Wikipedians freely volunteer their services; plus openness to experience is associated with intellectual interests and Wikipedians help promulgate knowledge. The authors argued that the prosocial behaviour associated with sharing information on Wikipedia is associated with ‘egocentric motives’ rather than altruistic ones. They also claimed that the surprisingly lower openness of Wikipedians also reflected these ‘egocentric motives’. There are some problems with the authors’ conclusions. The most glaring one is that their stated conclusions about openness to experience contradict the data they provide in the article: see the Table below for an excerpt.

Differences in average personality traits reported in the study (note that a 1-5 scale is used)

Openness to experience



As can be seen, contrary to their statements, Wikipedia members of both sexes actually had higher means on openness to experience compared to non-members, not lower as the authors stated. Perhaps the authors’ were confused by the presence of a serious typographical error that appears in the Results section of their article (on p. 680). The sentence starts off saying “a significant difference was found for the openness trait” but then goes on to say, “that is, the average agreeableness trait among Wikipedia members was significantly lower…” (Emphasis added). The phrase containing “agreeableness” is a repetition of a phrase from the previous sentence that actually discussed the results for agreeableness. In the Discussion section they then go on to state that Wikipedians were in fact lower in openness to experience (perhaps they wrote this after reading the typo in their Results) and then go on to speculate about why. But of course, since their results are back-to-front, their conclusions about openness to experience make little sense.

Another thing I found odd was that having decided on the counter-intuitive finding that Wikipedians, with their open sharing of knowledge and ideas, are actually low in openness to experience, they then interpret this in terms of “egocentric” motives. Although correct that Wikipedians were somewhat lower in agreeableness than non-members, and lower agreeableness may be associated with greater egotism, there is no research evidence linking egocentric motives to low openness to experience. Since the results actually showed that members were higher not lower in openness to experience compared to non-members, it seems possible that they are also motivated by greater intellectual curiosity and love of knowledge than non-members, motives actually known to be consistent with high openness to experience. 

Now let’s consider the results for agreeableness. While true there was a statistically significant difference, how large was it really? For female members the average difference was 0.44 and for males it was 0.16. Considering that this is on a 5-point scale, a difference of less than half a point is not a huge one. And also consider that although somewhat lower, the average agreeableness for Wikipedians still scored above 3, the mid-point of the scale. A reasonable interpretation would be that although somewhat less agreeable, they were not particularly disagreeable either. The authors speculated that lower agreeableness was associated with “egocentric motives”. However, agreeableness is a very broad feature of personality that has a number of components, so the result is open to a range of possible interpretations. One possible explanation, admittedly speculative, is that members might be more argumentative than non-members and hence more willing to engage in debate, and debate is a daily occurrence on Wikipedia.

One final discrepancy in the research report was that in the report's Abstract, the authors reported that Wikipedians were lower in conscientiousness than non-members, although they did not state this conclusion anywhere in the body of the report. Info in their Table of results (not displayed here) shows that male members were somewhat lower than male non-members, but female members were slightly higher than female non-members, so the differences in conscientiousness are inconsistent across gender. The authors did note that females generally were significantly higher in conscientiousness than males, which fits with their Table’s results.

So rather than saying that Wikipedians are “grumpy and close-minded” due to “egocentric motives” as so many of us have been led to believe, it may be closer to the truth that they are actually “argumentative and open-minded” perhaps due to their passion for sharing information. But to be really honest, the results are still open to interpretation because these are fairly broad personality dimensions that encompass a range of narrower personality traits. To determine if Wikipedians actually are guided by egocentric motives, it would be necessary to use more specific measures than the Big Five, such as a measure of narcissism perhaps. The moral of the story seems to be to check the source of your information carefully for accuracy rather than just believing whatever you read before spreading it around. 

ADDENDUM: According to a 2011 survey of Wikipedia editors over 91% of editors are male. As noted above, the difference between male members and non-members on agreeableness was even smaller than the difference between females, so it seems fair to say that the case for Wikipedians being "grumpy" has been overstated! 

Yair Amichai–Hamburger, Naama Lamdan, Rinat Madiel, and Tsahi Hayat (2006). Personality Characteristics of Wikipedia Members CyberPsychology & Behavior, 11 (6), 679-681 DOI: 10.1089/cpb.2007.0225

A new version of this article now appears on my blog Unique - Like Everybody Else at Psychology Today. 

Follow me on Facebook, Google Plus, or Twitter.

© Scott McGreal. Please do not reproduce without permission. Brief excerpts may be quoted as long as a link to the original article is provided.