Tuesday, October 2, 2012

Another "Extreme Female Brain" Sighting

EXECUTIVE SUMMARY: Simon Baron-Cohen's E-S theory of autism, sex differences and whatever else he's applied it to lately states that people have one of three basic cognitive styles: Type E, the empathizer, who understands people and relationships; Type S, the systemizer, who understands abstract ; and Type B, who can do both. Prof. Baron-Cohen has identified autism as exemplifying the Type S cognitive style taken to extremes, but hasn't written much about its opposite, the extreme Type E, or Extreme Female Brain. He allows that it must exist, but he doesn't think it would be as disabling in modern society as an Extreme Male Brain --- autism --- is. Other people (Crespi and Badcock) have suggested paranoid psychosis as the condition typical of the Extreme Female Brain, as it involves being morbidly obsessed with other people. In the paper I discuss here, a pair of evolutionary psychologists make the case that the psychopathology characteristic of the Extreme Female Brain is disordered eating.

The paper I discuss in this blog post describes a series of four different "experiments" in which groups of college students, of varying size (as large as n = 160, as small as n = 37), are given multiple psychometric exams. They are tested for the following things: disordered eating, sensitivity to other people's judgments, Empathizing Quotient (EQ), Systemizing Quotient (SQ), performance on various tasks considered representative of either empathizing or systemizing (e.g. guessing what emotion people in photographs are feeling, or mentally rotating three-dimensional objects), and schizotypal personality disorder. Some of the data are compatible with the idea of a high-empathizing, low-systemizing Extreme Female Brain that is particularly susceptible to disordered eating, and some are not.
Still image from a short film made in 1967 by Roger Patterson and Robert Gimlin, showing what appears to be a person in a gorilla suit walking in some woods
Thought to exist, but seldom glimpsed in the wild
Today on the fascinating psychology blog BPS Research Digest, I saw that some other researchers think they've found a candidate for an Extreme Female Brain, which according to Simon Baron-Cohen's E-S theory ought to exist, probably in about the same numbers as the Extreme Male Brain (which he identifies as autism) does, but which hasn't been described in the psychological literature.

The new article, by evolutionary psychologist Gordon G. Gallup, Jr. and assistant professor of psychology Jennifer Bremser --- both affiliated with the State University of New York --- and published in the journal Evolutionary Psychology, tries to make the case that eating disorders stem from the heightened sensitivity to others' judgments that is characteristic of the Extreme Female Brain.

What they did was to give a group of undergraduate psychology students at SUNY a battery of tests: the Eating Attitudes Test (EAT), which looks for disordered attitudes about eating (sample questions: "I feel extremely guilty after eating"; "I feel that food controls my life"); the Fear of Negative Evaluation Scale, which measures how anxious you are about what other people think of you (sample questions: "I often worry that I will say or do the wrong thing"; "I feel very upset when I commit some social error"; "When I am talking to someone, I worry about what they may be thinking about me"); Simon Baron-Cohen's Empathizing and Systemizing Quotients (which I have critiqued here and here); the Schizotypal Personality Questionnaire (PDF), which tests for nine traits associated with schizotypal personality disorder: ideas of reference (which means thinking that other people, or the media, are talking specifically to or about you when they aren't really), excessive social anxiety, odd beliefs or magical thinking, unusual perceptual experiences, odd or eccentric behavior, a lack of close interpersonal relationships, odd speech, constricted affect (i.e., not being very good at showing one's feelings), and general suspiciousness; and several tests that measure skills that would be associated with either an empathizing or systemizing cognitive style: the Reading the Mind in the Eyes Test, the Intuitive Physics Test and the Redrawn Vandenburg and Kuse Mental Rotations Test (Version A). Then they looked for relationships between all of these different test scores, and between any given score and the test taker's sex.

Their hypothesis --- that an empathizing cognitive style is more characteristic of women than of men, and tends in its extreme form towards disordered eating and social anxiety --- would predict the following: women scoring higher, on average, on the EQ and Mind in the Eyes tests, and lower on the SQ, Intuitive Physics, and Mental Rotation tests; women scoring higher than men on the measures of disordered eating and fear of negative evaluation, and high scores on those measures being correlated with high scores on the EQ and Mind in the Eyes tests for both sexes. 

They found significant differences between the sexes on the measures of disordered eating and fear of negative evaluation (both were higher for women), and also on the EQ, but not on the SQ. Women were also likelier to display something called "empathizing bias", which they defined numerically as each study participant's z-score on the EQ minus their z-score on the SQ. (Z-scores are a measure of how far an individual's score on a given statistical measure is above or below the average score. A negative number means the person, or sub-group, scored below average, while a positive number means they scored above average). Thus, the empathizing bias score is supposed to represent how much better a person does at empathizing than systemizing (or not, if it's zero or a negative number).

There was also a disparity between how participants scored on the EQ and SQ versus how they did on the more "objective" measures of systemizing or empathizing skill, the Intuitive Physics, Reading the Mind in the Eyes and mental rotation tests. The sexes differed strongly on their (self-reported) EQ scores, but performed almost identically on the Reading the Mind in the Eyes test. Obviously guessing what emotion a black-and-white photograph of a stranger's eyes is meant to convey is very different from accurately gauging the emotional states of one's relatives and friends, so that still leaves open the possibility that women perform better at this task when it involves real people who are known to them, but it's just as likely that women tend to overrate, and men to underrate, their interpersonal sensitivity on self-reported measures, and that real differences between the sexes on this ability are minimal. 

The opposite pattern occurred between the SQ and one of the "objective" measures of systemizing ability: men and women scored equally on the SQ, but men outperformed women on the Intuitive Physics test. (I can't find any results on the mental-rotation test broken down by sex).

There was also a very inconsistent pattern of correlations between disordered eating, fear of negative evaluation and the various systemizing and empathizing variables. High scores on the disordered-eating measure correlated with high scores on the fear-of-negative-evaluation (FNE) measure, and also with high scores on the EQ. There was no relationship between SQ scores and either disordered eating or fear of negative evaluation, and EQ and SQ scores were positively correlated with each other. Most strangely, SQ scores were correlated positively with empathizing bias: the number that reflects the imbalance between one's empathizing and systemizing abilities!

Also, within each sex the overall pattern of disordered eating patterns correlating with greater empathic ability (whether self-reported or "objectively" measured) seems to fall apart. 

Two graphs, Figure 1 and Figure 2, show bars for average male and female performance on both the EQ and the Reading the Mind in the Eyes Test, at low and high ends of the disordered-eating spectrum. According to these graphs, women score about the same on these tests regardless of whether they show disordered eating patterns or not, and for men the results are all over the place. On one test (the Mind in the Eyes), men who score low on the Eating Attitudes Test do equally well with all women, while men who score higher do more poorly on average, but their range of results is very, very broad. The error bar is wider than the bar on the graph is tall. 

On the EQ, the men show more or less the pattern the researchers expected: men at the high end of the disordered-eating spectrum scored higher than men at the low end on average, but for the former group especially there was a lot of within-group variation.

They also found correlations between disordered eating, fear of negative evaluation and several of the traits that make up schizotypal personality disorder: disordered eating correlates positively with ideas of reference (i.e., thinking everything refers to you, specifically), magical thinking and suspicion. Fear of negative evaluation correlates positively with ideas of reference, suspicion, social anxiety and constricted affect. (This latter makes sense --- if you are afraid people are judging you, of course you are going to try and minimize the extent to which those people are able to tell what you're thinking or feeling! It's called a "poker face".)

They also wanted to see if any of these psychological problems --- disordered eating, fear of negative evaluation, schizotypal personality disorder or any of its component traits --- interfered with one's ability to rotate three-dimensional objects in one's head. (Their reasoning for doing this wasn't just for giggles --- let's take a bunch of emotionally stressed people and ask them to do something both pointless and difficult! Hilarious! --- it can be hard to shake the idea that a lot of psychological experiments are done with precisely that objective --- but because they wanted to see if people who were unusually and morbidly concerned with what other people thought of them, and were thus "hyper-mentalizers" who would be reckoned extreme empathizers in Simon Baron-Cohen's typology would also show the expected impairment in systemizing tasks. 

Annoyingly, they did not compare people's scores on the mental-rotation task with their scores on other direct measures of systemizing or empathizing ability: they assumed, given earlier findings, that high scorers on the measures of disordered eating and fear of negative evaluation are also high empathizers. As I have said above, the data are less than clear in their support of this assumption. 

They found that people (they do not break it down by sex, probably because at this stage in the study they were dealing with a lot fewer participants) who scored high on their measure of disordered eating tended to do worse at mental rotations, consistent with their prediction. However, they also found a small (too small to be significant) positive correlation between mental-rotation scores and fear of negative evaluation. Of those two things, I'd consider the FNE score to be the more pure indicator of a "hypermentalizing" excess of concern for what other people think; there's a lot that's still unknown about the psychology of eating disorders, to the point that calling disordered eating a behavior born out of a fear of negative evaluation by others would be speculative.

The correlations they found between the various schizotypal personality traits and mental rotation ability surprised me, too. You'd think, if greater skill at mental rotation of three-dimensional objects indicated a logical, "systemizing" type of mind, that there would be a strong negative correlation between mental-rotation scores and those schizotypal traits that bespeak irrationality, like magical thinking or ideas of reference. (Especially magical thinking). But no, there's no correlation between either of those things and how well one does at mental-rotation tasks. The only components of schizotypal personality disorder that showed any significant relationship to mental rotation were social anxiety and constricted affect, both of which were negatively correlated. 

A negative correlation between skill at mental rotation and one's score on the social anxiety subscale of the Schizotypal Personality Questionnaire does fit with the researchers' idea of "hyper-mentalizing" at the expense of systemizing. But the lack of such a correlation with fear of negative evaluation does not fit, and instead makes one wonder if what's going on is, instead, anxious people's anxiety interfering with their ability to perform the rotations. 

In their Discussion section, the researchers do not comment on most of these discrepancies, but the one they do address --- worse performance on the Reading the Mind in the Eyes Test* by people with more severely disordered eating --- they attribute to those people's having greater, not less, emotional sensitivity**. Why, they're so sensitive they see things that aren't even there, so they do poorly on certain tests of emotional sensitivity and interpersonal acuity like the Reading the Mind in the Eyes Test.

I'm being silly, but that really is their explanation:
Comparable to the heightened sensitivity to sensory stimuli (auditory, visual and tactile) common among people with autism, individuals with the EFB [Extreme Female Brain] may be hypersensitive to social stimuli. Disordered eating may ameliorate the experience of negative evaluation anxiety that results from heightened sensitivity to social stimulation. 
Consistent with this idea, emotional processing deficits have been linked with eating disorders including the inability to recognize, label and describe emotions in detail and to link feelings with bodily correlates (Bourke, Taylor, Parker and Bagby, 1992 [link]; Eizaguirre, de Cabezon, de Alda, Olariaga and Juaniz, 2004 [PDF]; Garner, Olmsted and Polivy, 1983 [link]) Also, compared to healthy controls, women with anorexia had difficulty recognizing emotions from facial expressions and vocal tones (Jansch, Harmer and Cooper, 2009 [link]; Kucharska-Pietura, Masiak and Treasure, 2003 [link]).
Jones, Harmer, Cowen and Cooper (2008) [link] investigated emotional face processing in female undergraduates with high and low levels of disordered eating. Participants completed the Eating Attitudes Test-26 and the Facial Expression Recognition Task, a computer task in which participants view faces depicting 7 different expressions (anger, disgust, fear, happiness, sadness, surprise, and neutral) at different intensities. The participants with higher levels of disordered eating were less accurate in identifying happy and neutral faces. Among participants with high levels of disordered eating, there was a tendency to classify more happy faces as neutral, and more neutral faces as either angry or sad. In addition, there was evidence that reaction times to recognize disgust were longer, while reaction times to recognize fear were faster than participants with low levels of disordered eating. When disordered eating reaches clinical levels, the effects of hyper-mentalizing may manifest as mental state misattributions. This may be because they are using their own experience to model the experience of others, and their bias to classify emotions with a negative bias may influence their attributions. For instance, when shown pictures of women who are said to have overeaten, females with high levels of disordered eating ascribed more negative emotional states to these women than control participants do. Thus, women with higher levels of disordered eating appeared to use their own experience of overeating to describe how the other women would feel (Beebe, Holmbeck, Schober, Lane, Rosa, 1996 [link]).
It is also possible that the physiological and cognitive effects of starvation produce deficits in performance. In a study looking at performance on the Reading the Mind in the Eyes Test, individuals with anorexia performed worse compared to healthy controls (Russell, Schmidt, Doherty, Young and Tchanturia, 2009 [link]. 
An alternative explanation is that low scores on the Reading the Mind in the Eyes task does not represent a deficit of theory of mind ability, but rather an excess that reflects hypermentalizing. Abu-Akel (2003) [PDF] suggests that theory of mind dysfunctions range from the complete absence of the ability to represent other people's mental states (as shown in severe autism) to having the representational understanding of mental states, but a deficit in the ability to apply this understanding (as in Asperger's syndrome) to the abnormal or excessive attribution of mental states (as in schizotypy). It may be that this third class of dysfunction is misconstrued as a deficit, rather than an excess. Consistent with this interpretation, the RME is one of the most widely used instruments to investigate theory of mind performance in adults; however, scores on the RME depend only on accuracy. The test does not identify the nature of the errors that impede performance. For example, there can be errors of absence (failing to detect a mental state when it is present) and errors of excess (wrongly inferring a mental state in its absence). We suspect the second class of errors (errors of excess) account for most of the lower scores on this test among individuals with anorexia.
(They also seem to be arguing that people cursed with an excessive degree of awareness of other people's judgment of them might be self-medicating by starving themselves: if they are women, they will produce much less estrogen, which the authors believe "may also produce changes in empathizing and theory of mind performance." So that's a novel proposal --- people with eating disorders starve themselves to dull their razor-keen interpersonal sensitivity, in the interests of making their lives bearable. Obviously there's no evidence for this, and I've never seen anyone who has an eating disorder describe it like that, but at least it does people with eating disorders the courtesy of treating them as rational beings, which not all of the accepted explanations do.)

I do not doubt at all that people who have this kind of hypersensitvity exist --- I know a few! What I doubt is that 1) these people are all the same, and all have this skill for the same reason; 2) these people are any likelier to develop eating disorders than the general population; and 3) these people are necessarily bad at "systemizing," which seems to include such things as logical reasoning, pattern recognition, organization and spatial cognition. Indeed, the data from this same study suggest that people who are good at one half of the empathizing/systemizing duality seem to be good at the other half, too.

You can also count me as agnostic, still, on the question of whether women are, overall, better empathizers and men better systemizers. I don't rule it out, as at least some cognitive differences between the sexes do seem to exist, and show up consistently in studies, but as yet I don't see strong empirical support for it. 

Also, they dance around this in their Discussion section, but never directly address it: disordered eating is quite common in autistic girls and women, and even non-autistic people with eating disorders, particularly anorexia, perform similarly to autistic people on tests of mentalizing ability (the Reading the Mind in the Eyes test again), mirror self-recognition, emotion recognition, body awareness, executive function and central coherence (the Embedded Figures Test).

If autism is supposed to be the Extreme Male Brain, and the Extreme Female Brain is supposed to be its opposite, doesn't that complicate things a lot? 

Bremser JA, and Gallup GG Jr (2012). From one extreme to the other: Negative evaluation anxiety and disordered eating as candidates for the extreme female brain. Evolutionary psychology : an international journal of evolutionary approaches to psychology and behavior, 10 (3), 457-86 PMID: 22947672

*In the present study, it was only the male participants who showed this pattern, but the researchers cite lots of other studies of people with eating disorders, particularly anorexia nervosa, who show the same impairment. Some of the other researchers hypothesized that insufficient nutrition made those patients less able to perform complex cognitive operations of any sort, which sounds convincing to me.

**I am having UNBELIEVABLE trouble spelling "sensitivity" today. I always seem to leave out one of the "I's".  


Scott McGreal said...

Thanks for a great article, this is an insightful critique of the odd conclusions drawn by the authors. Seems like Gordon Gallup has done it again - in 2002 he made far-fetched claims about the antidepressant properties of semen based on a correlational study with no biological evidence. I have written a critique of his semen study on my website if anyone is interested.

Sister Wolf said...

Aha! I just wrote a comment on your earlier post about Extreme Female Brains before reading this. I had severe anorexia as a teenager. Now I just have problems seeing my body clearly. I forgot what that's called. I look forward to investigating this study.

I do recall a study of eating disorders that suggested a correlation with an imbalance of estrogen in utero. And this goes along with studies suggesting that autism may be connected with testosterone levels in utero.

Finally, I forgot to mention that I have a son with Aspergers. This is how I discovered Dr. Baron-Cohen.

Best, Sister Wolf