Tuesday, March 31, 2009

Motor learning and memory

Dorfberger et al (2009) suggests an alternate explanation to the male advantage on certain motor tasks: this study of Israeli schoolchildren found that training sessions improved male performance more, and that the boys retained skills for longer, than similar interventions for girls. The study concludes that, especially during adolescence, "there may be a male advantage in motor learning rather than in motor performance per-se". An earlier PET investigation (Grafton et al, 1992) had uncovered no neurological sex differences during motor learning, but this is not surprising given their small sample size (n = 6). Dorfberger's result may only be applicable to young populations, however: Smith et al (2005) found no sex differences in acquiring or retaining motor memories in adults aged 18 to 95.

Motor skills, with the exception of a male advantage in aimed throwing (2/24/09), have not really been discussed in previous Difference Blogs. All of the motor tasks studied in the above experiments involve fine motor control: largely writing and finger manipulation. Despite Dorfberger's assertion, I've seen little evidence for a male advantage in fine motor skills. This is usually presented as a female advantage. A summary of the research on female fine motor advantage is available in Diane Halpern's Sex Differences in Cognitive Abilities (2000, pp 89-90) However, this advantage refers to performance, rather than to skill acquisition or retention.



I don't think much about fine motor skills, especially their retention. The motor memories that I notice most are larger -- for example, riding a bicycle. Now, I suspect that most people learn to ride a bicycle well before the age shown to have a male advantage in Dorfberger (12), but retaining that memory has proven especially hard for me, as mentioned several times before. I'm trying to think of other motor memories I've developed, and I really think typing is the most invested, since I don't play an instrument.



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Monday, March 30, 2009

Death and Diet

In the current Archives of Internal Medicine, Sinha et al (2009) report that a 10-year prospective study of meat intake showed increased risk of death among both men and women in the top quintile of meat-eaters (vs. the lowest quintile). Counter-intuitively, men in the highest red-meat quintile showed increased risk of "death from injuries and sudden death" as well as from cancer and cardiovascular diseases. There was no relationship between accidental death and meat consumption for women. This seems run counter to arguments made in Lawlor et al's (2001) retrospective study; Lawlor et al suggested that men and women may respond differently to dietary fat, although they acknowledged that dietary fat sources might differ by sex. According to Lawlor et al, total dietary fat consumption has not historically differed between the sexes.

For example, Lawlor suggests that war-time food rationing in the U.K. might have reserved more of the scarce red meat for men, with women eating more alternative protein sources, such as fish. In previous DB posts, we've seen that women view dairy as more key to nutrition (2/19/09), and that older men seem to have higher protein needs to maintain muscle mass (3/26/08). Women also seem to eat more vegetables than men, according to some studies (3/21/08).



I think what I found most interesting about Sinha's study was that there did not seem to be a difference between men and women on meat intake in general. This could be related to the fact that Sinha's study group was drawn from AARP members, with several differences from a typical U.S. population of this age group: "predominantly non-Hispanic white, more educated, consumed less fat and red meat and more fiber and fruits and vegetables, and had fewer current smokers".

I think I've accepted the fact that I love red meat. Periodically I try to cut down. I don't consider it the most environmentally or medically wise choice. It's damn tasty, though.



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Friday, March 27, 2009

Ambition gap narrowing

A new study released by the Families and Work Institute (2009) reveals that 26% of women in dual-income households are now earning more than their husbands. In the New York Times' Motherlode blog (2009), Lisa Belkin focuses on a change in motherhood's impact on career ambition: in 1992, the presence of children reduced a woman's desire for more work responsibility by 18%; in 2008, the gap was 3%.

Changes were apparent in the fatherhood role as well. Over the three decades studied, 59% of men in 2008 experienced "some or a lot" of work-life conflict, compared to just 35% in 1977. Women's work-life conflict over the same period was stable: 41% in 1977 and 45% in 2008. The increase in men's work-conflict is probably due to increased parental investment: 31% of women in 2008 said their husbands took at least equal responsibility for parenting: "Interestingly, 49% of men reported taking as much or more responsibility for the children as their wives, indicating a perception gap."



So, one of the reasons I started writing DB in the first place is because I felt like I had three views of gender: living as a woman, living as a man, and as an outsider to the whole damn game. In no part of my life is this more apparent to me than in discussions of parenting, which feel like they come up a lot: this post makes three this week that end up coming down to "women can has babies." This feels like a tangent, but I really want to express a little self-disgust here: manhood and womanhood are more than fertility. Or are they? Does my sterility make me as much of an outsider as my tripartite perspective?

Returning to the Family and Work Institute's results, I have to say that I am disappointed that I don't see a way to compare their findings with single-income households. In fact, I'm not seeing a good way on the U.S. Census site to separate single-earner families from single-person households. Anyone else want to take a stab at what percentage of couples are getting by on one income?



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Thursday, March 26, 2009

Male Contraception

Nelly Oudshoorn's book, The male pill: a biography of a technology in the making (2003) points out that although the feasibility of a male birth control pill was demonstrated in the 1970's, there is still no such product available. Early opinion surveys focused on class and gender differences, such as Balswick (1975) who stated that "any attempted reeducation process must take into account the lower-class male's fear of emasculation." According to a survey of 1,930 men by Thompson (2008), over half of men desire "more personal control over their fertility", and 96% are willing to visit a doctor in order to get a new method of male contraception. According to Thompson, belief persists among contraceptive developers that men would not embrace a drug-based birth control method, but the results of the survey contradict this stereotype.



In the 1980's, I knew a man who claimed to get a male birth control pill from Canada, saying that it wasn't available in the U.S. The man was a compulsive liar in pretty much every area of his life, but being 12, I believed him. As an adult, I question his motives for sharing this "fact" with a 12-year-old (he didn't actually make a pass at me that I noticed), as well as shudder to think about the girls he probably did convince to have unprotected sex with him.

Here's the thing: I feel like the male-birth-control thing is tied up in a Catch-22 with the social responsibility for pregnancy. I feel like the current laws regarding child support are unfair to men, but also that changing them would be unfair to women. I get furious when I hear things headlines like "Sperm Donor Sued for Child Support", even though the sources are often reactionary crap (two examples: FOXnews, 2005; NY Post, 2007). There is no opt-out for men when it comes to child support, but I feel like this option can't be given until there is more equal responsibility for preventing pregnancy.



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Wednesday, March 25, 2009

Pain sensitivity

Women typically show higher sensitivity to pain in experiments, and so naturally, hormones are suggested as one possible contributor. However, the studies we've examined do not seem to support a hormonal explanation. Last year I spoke to Arthur Arnold about his experiments with gonadiectomied mice (see comments 4/30/08) which showed that female (XX) mice appeared to be more sensitive to pain independently of hormonal state.

Two studies released this year also attempt to address this theory. Klatzkin et al (2009) is notable because it uses human participants instead of an animal model. Klatzkin's study found that menstrual cycle did not affect experimental pain sensitivity in women. This would seem to suggest that the hormonal avenue may be a dead end in pain studies. However, Li et al (2009) may have found a promising line of inquiry in another mouse study: two strains of knockout mice who were missing estrogen receptors α or β did not show sex differences in pain sensitivity, while the wild-type mice did. Li et al suggest two possible explanations: "an ongoing effect of estrogen acting through its receptors in females or the developmental changes that predominantly affect females." By developmental, the authors are referring to Fan et al's (2007) suggestion that estrogen receptor β may be key to the development of pain pathways in the brain.



Given the other evidence we've looked at, I suggest a third explanation: what if the estrogen receptors react to compounds other than estrogen? Neurobiology was a couple of years ago, but I seem to remember that some receptors served double-duty. There may be some really obvious medical or neurological reason why this wouldn't be the case here, but it seems to me that the gonadiectomied mice discussed last year would have the receptors, but not the hormones, and that the knockout mice have the hormones, but not the receptors. The gonadiectomied mice showed sex differences in pain sensitivity, and the knockout mice didn't.

More on pain:
Conference on Women's Pain: 10/10/06
Neuroscience of Sex differences in pain perception: 5/14/08
Physical vs. Emotional pain: 9/26/06


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Tuesday, March 24, 2009

Parental investment under uncertainty

Paternity testing is a popular theme for daytime talk shows: popular media make it seem as if large portions of the population are uncertain about their heritage. One British paternity testing vendor suggests that "up to one in twenty-five dads are not the real father"(International Biosciences, 2009). The Wikipedia article on "Parental testing" points out that tests can be used to determine motherhood or fatherhood, although cases of maternity testing are rare, occurring for cases such as hospital errors, birth-parent identification for adopted children, and confirming the parentage of embryos used in in vitro fertilization.

Many factors appear to influence the prevalence of paternity testing: Gilding (2006) describes "political, cultural and economic" reasons why the DNA paternity testing occurs 5x as often per capita in the United States compared to Australia. Bishai et al (2006) point out that among the 300,000 DNA paternity tests conducted annually in the U.S., demographic variables are not good predictors of the tests' outcomes: no race or ethnic group has particularly different outcomes from the overall 72% likelihood that the test will confirm fatherhood. Anderson's (2006) analysis suggests that a man's decreased confidence in parental status has significant implications on his investment in his children.



I'm reminded of a terrible and offensive joke I read in college: "there's a new day-after pill for men; it changes your blood type." It's representative of the idea that men, but not women, can run away from pregnancy. I'd have to agree that this is true, for pregnancy, if not for childcare. The ability to deny parentage seems like a major sex difference that I haven't really addressed, and probably because I find it altogether too depressing. Fighting for women's reproductive rights is really important to me, but I'm constantly nervous about what seem like unfair obligations imposed on biological fathers.

Perhaps the Gilding article is the most relevant to my feelings on the subject: in a different cultural and political climate, where legal obligations to children were different, parental testing would be less common, and less desired. I'd like to see analysis of the parental investment of adoptive fathers, as a comparison to uncertain vs. certain fathers.



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Monday, March 23, 2009

Reading habits

A survey (n = 2,000) conducted as part of the U.K.'s National Year of Reading (2008) suggests that men are less likely to finish books than women (Telegraph, UK 2009). The Guardian (UK, 2009) reports this as women knowing how to "read properly", while the Telegraph points out that men reported being more likely to lie about their reading habits to impress a member of the opposite sex (46% to 33%). These findings are not entirely surprising nor limited to the U.K.: in a Dutch study (n = 664), Verboord (2005) found that women's book reading was 16% higher than men's. In a smaller U.S. study (n = 115), Scales and Rhee (2001) found that 41% of women vs 16% of men reported reading novels.

It's worth pointing out that these three surveys appear to be asking very different questions: do you finish what you read, how often do you read, and what do you like to read? However, Verboord did report high levels of concordance between reported answers on how often people read, how many books they finish, and when they last finished a book. Perhaps relevant is Rehberg Sedo's (2003) (n = 252) study of book club participants, who were 85% female: however, this probably says more about the social reading environment than with actual volume of reading.



If nothing else, this would seem to be support for the oft-cited female comfort with language-based tasks versus spatial or mathematical tasks. On the other hand, it might also be support for a female tendency to report more socially desirable behaviors: I don't think anyone is likely to argue that women are under social pressure not to read. If anything, women's vocal involvement in social reading (such as book clubs) might cause underreporting of reading in men. There's really no way to know how close the self-report in these (all retrospective) studies is to reality. I was hoping to find a reading diary study, but since diary-keeping tends to improve performance of desired behaviors, that couldn't be applied to the general population anyway.



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Friday, March 20, 2009

Do mothers carry the weight of the world?

In a 2000 review in Nature, Barry Levin suggested that the "obesity epidemic" in the developed world might be more complicated than "increased food intake or decreased energy expenditure". Levin's review suggested that genetic predisposition towards obesity might spiral upward through generations in what he terms "metabolic imprinting."

Last summer, several studies attempted to demonstrate this link. Aagaard-Tillery et al (2008) found that macaques who ate a high fat diet during pregnancy tended to have heavier children, even if they themselves did not become obese. Waterland et al (2008), using mice, suggested that a genetic tendency towards obesity grows worse over successive generations. However, Lawlor et al (2008) looked at human data from the Avon Longitudinal Study of Parents and Children and found that the difference between maternal and paternal contributions to children's obesity was not significantly different, calling into question the maternal "overnutrition" theory.

Sociologists Kwan and Trautner (2009) call into question the entire framing of the "obesity epidemic" by pointing out the trend toward medicalization and pointing out that the epidemic can be framed as a "moral panic" which preferentially targets women.



I think we can agree that women are under more social pressure about their weight than men (e.g. 4/10/08, 1/22/07), and as previously discussed, women may be more susceptible to social pressure than men (e.g. 3/10/09, 2/26/09). The idea of a "moral panic" and the focus on maternal obesity brought this into a pretty sharp perspective for me this morning: my emotional reaction was that these studies were blaming mothers for their children's obesity. "Not only are you a failure as a woman for being fat, but you are a failure as a mother because you made your child fat." I'm finding myself surprisingly pissed off about it. The fact that Lawlor's study seems to be the only one looking at paternal genetic contributions to obesity is shocking, but probably shouldn't be.



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Thursday, March 19, 2009

I am Jack's prostate

Two new studies reported by the BBC today indicate that the routine prostate cancer screenings recommended for men since 1987 may do more harm than good (BBC, 2009) Current testing procedures require speedy, and often invasive, follow-up tests for a higher percentage of men than actually need care:
"Critics will argue that this translates into a benefit for only one in 1,400 men, while around one in 30 men were harmed because they had to deal with the diagnosis and treatment of prostate cancer that would never otherwise have caused any problem."

Andriole et al (2009): U.S. results of Prostate Screening, NEJM
Schröder et al (2009): European results of Prostate Screening, NEJM


I don't think I've covered prostate cancer before, which struck me as desperately unfair when I considered that I've covered menstrual-based differences several times (examples). Now, I don't think the problem implicated here is unique to men; for example, I have serious doubts about the risk-benefit ratio for some of the HPV tests available to women, and aggressively advertised on TV and in magazines.

edit: Please see comments for discussion of HPV Vaccine risks.



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Wednesday, March 18, 2009

Olfaction to Action

Tubaldi et al (2008) argue for a sex difference in olfaction in "an action context". The study attempts an olfactory interference task (like Stroop, but for smell) by mismatching a grasping target and an olfactory cue. The study found greater interference between smell and action for men than for women, which the authors argue is related to differently evolved roles:
In other words, female sense of smell would be perception-oriented, ie optimised to detect, discriminate, identify, recognise, and categorise odours. Conversely, male sense of smell would appear to be action-oriented, ie tailored to elicit specific and selective motor commands for interacting with `smelled-objects'.


I'm a little confused about this one. I'm not really sold on their graphs as demonstrating anything particularly significant. The idea that action-vs-perception are different modes of sensory processing is an interesting one, and probably worth testing. I feel like this would be related to the tendency of women to self-report emotional states incongruous with their neurological state (see 1/21/09), but that would suggest greater interference for women, not men. Since this is an interference task, their control is "congruent" smells versus "incongruent" smells, but I feel like the test procedure is so novel that additional controls should be in place. It looks like women's "grasp" time was shorter than the men's across all conditions.

Related posts:
The Nose Knows (women's reaction to male sweat) 2/17/09
Smelling your way to happiness (scent and attraction) 5/19/08
You smell (neurological dimorphism in olfaction) 2/7/07



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Tuesday, March 17, 2009

Aspirin

In a statement published in today's issue of the Annals of Internal Medicine (2009), the U.S. Preventive Services Task Force (USPSTF) updates the guidelines for preventative aspirin regimens. USPSTF member Dr. Michael LeFevre said in a US News & World Report (2009) article: "We have a recommendation for men and a recommendation for women. We did not have that before."

The USPSTF 2002 aspirin recommendations recommended that aspirin therapy be recommended for "men older than 40 years of age, postmenopausal women, and younger persons with risk factors for coronary heart disease." However, the new guidelines suggest a narrower band of appropriate ages, and that for women, the reduction in stroke risk is the major benefit, not the reduction in cardiac risk. The 2009 recommendations are as follows:
  • Encourage men age 45 to 79 years to use aspirin when the potential benefit of a reduction in myocardial infarctions outweighs the potential harm of an increase in gastrointestinal hemorrhage (A recommendation)
  • Encourage women age 55 to 79 years to use aspirin when the potential benefit of a reduction in ischemic strokes outweighs the potential harm of an increase in gastrointestinal hemorrhage. (A recommendation)
  • Evidence is insufficient to assess the balance of benefits and harms of aspirin for cardiovascular disease prevention in men and women 80 years or older. (I statement)
  • Do not encourage aspirin use for cardiovascular disease prevention in women younger than 55 years and in men younger than 45 years. (D recommendation)



One of the earliest DB posts (9/8/06) was a complaint about the treatment of women with evidence that had been found solely in men. I really feel heartened by these revised recommendations, no pun intended. Actually, re-reading the commentary section of that post, I see that it's not really a complaint. Two and a half years ago, I was nervous about medicine based on demographic subgroups; now, I think it's a good start. What a difference DifferenceBlog has made.



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Monday, March 16, 2009

Race and Recession

As we've already discussed (1/13/09), the current economic crisis has hit job sectors disproportionately staffed by men hardest. Men are losing jobs more than women, because the jobs being cut tend to be worked by men. Additional findings from Northeastern University's Center for Labor Market Studies suggest that race is an additional, possibly even larger, factor: black men's employment levels have dropped 7.8% in less than 18 months (Christian Science Monitor, 2009). In the same period, according to the CSM, black women have faced "no net job losses," possibly due to higher levels of education.

It is interesting to note how the face of economic struggle seems to have shifted over just a few years. Lovell and Salas (2003) noted that men's unemployment rates were falling, and women's were rising, as recently as 6 years ago, and these shifts were sharper among black men and women than in the general population. Labor participation rates may also be a factor: black women "in the labor force" increased 18.1% between 1996-2006, compared to 11.3% for black men (see 1/26/09 for a discussion of the Labor Bureau definition of workforce).



I often wonder how useful it is for me to talk about "gender roles" at all. At least, I should include the caveat that my experience of gender roles has a middle-class (liberal, academic) white bias, and a fairly strong one at that. One quote from Sheri Parks in the CSM article really brought this home to me:
“If you’re a black woman, you don’t have to convince someone that you’re strong and nurturing and able to do almost anything – it’s almost a brand,” says Ms. Parks. “The prevalent image of a black man is what we call hyper-masculine and often idealized, but not necessarily in the workplace.”
In the Difference Blog Reader Poll, I asked about gender, but I haven't asked about race. I don't know how many of you have experiences different than mine. Still, I feel like this is a good time to re-state the obvious: gendered experience is a cultural experience, and varies in ways I can't imagine.



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Friday, March 13, 2009

Bicycling Gap

"In the UK, the image
associated with cycling
is male, often in Lycra,
quite likely to be moving
at speed and often not a
very friendly person –
possibly aggressive."
-- Henrietta Sherwin,
Centre for Transport
& Society
BikeRadar (2009), "the world's most comprehensive cycling website", reports on why women in the UK seem to be less likely than their male counterparts to go it on two wheels. Cycling England (2008), for example, suggests that men are three times more likely to ride than women.

The reasons for the disparity may differ between cultures. The surveys suggest that women often cite sweatiness and helmet hair as potential reasons that they do not cycle. In Australia, Garrard et al (2008) found women were more likely to cycle when separated bike paths were available. In Portland, Oregon, Dill and Voros (2007) found that more women than men cited traffic as a barrier to bicycling. These concerns suggest that a gender difference in risk tolerance may contribute to the gap in cycling rates.



I hate the fact that this is true about me, but this may have motivated me to get back on the bicycle this spring. I've gotten private feedback from DB readers that they find themselves trying to fight the gender-stereotyped behaviors I post about. I do it, too. I really believe in cycling as a sustainable mode of transportation, but I have a lot of fear about riding. I'm not good at it. Even on separated bike paths, I feel like I'm in the way of more serious riders. I'm slow and wobbly. I recognize that more practice would probably build confidence and skill, but during my last attempt (a couple of years ago), I got more nervous after a few rides, and stopped. I didn't keep it up long enough to get past the hump.



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Thursday, March 12, 2009

Estimated Desirability of Drinking

LaBrie et al (2009)* suggest that college women may be excessively drinking in order to impress the opposite sex, and it isn't working. Their survey of over 3,000 college students found that 71% of women overestimated the amount a man would want a female friend, date, or girlfriend to drink, and high estimates were linked with higher reported drinking. On average, women thought men preferred a woman who would drink 4.75 "standard" drinks on a typical drinking occasion; men reported preferring 3.18 drinks.

Not much research appears to be available on the gender-construction of drinking in the U.S. college population, as opposed to the U.K., where "ladettes" and portrayal of "feminine drinks" in teen magazines have been an active inquiry for several years (see DB 10/3/06 & 7/7/08; Jackson, 2006; Lyons et al, 2006).

*Not yet available in abstract databases: see EurekAlert (2009) for a summary or download the full article from the Psychology of Addictive Behaviors journal page



I can go ahead and say I was guilty of trying to "keep up" with my male friends' drinking in college. (Hell, I'm probably still guilty of it to a degree.) I was smaller than them, and my fat-to-muscle ratio wasn't comparable either, so I ended up hurting myself more often than I should have. I don't think I was consciously trying to be more attractive, but I definitely thought it would earn me respect if I could keep up. I think knowing my limits would have been more respectable, but I didn't think my limits would increase if I didn't push them, and I was desperately ashamed of my low tolerance (and still somewhat annoyed by it).

However, in my case at least, keeping up with the lads had layers of meaning that are probably missing in LaBrie's sample. For example, the study excluded the 3.7% of respondents who reported a non-heterosexual identification.



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Wednesday, March 11, 2009

May-December

Lehmiller and Agnew (2008) examine commitment and satisfaction of heterosexual women in age-gap and age-concordant relationships. Surprisingly, they found that although most people rate older-woman/younger-man relationships as the most likely to fail, younger women involved with older men were more likely to report feeling socially stigmatized. The stigma reported by people in age-discordant relationships may be very severe: earlier research by the same authors (2006) found that these couples report more social disapproval than interracial or same-sex couples.



I've gone a bit younger in a relationship, and it was touch-and-go. I've gone older in a relationship, and it was a terrible idea. My current relationships are with a man 13 months younger than me and a woman 2.5 years younger. They seem okay, but even the 2.5 year gap feels wide enough to make a difference sometimes.

I feel like this is an unpopular idea among some of the circles I run in, but I don't generally think large age gaps are a good idea. However, I disagree with Agnew and Lehmiller's definition of an age gap as being anywhere between 5 and 50 years. (and did they find a couple with an over 50 year gap?) I stick to the half-your-age-plus-seven rule... mostly.



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Tuesday, March 10, 2009

Differences in Self-Report

As we've discussed several times, when taking sexual histories from men and women, there seems to be a gender difference in reporting rates (e.g. 8/13/07, 10/28/08). An experiment by Alexander and Fisher (2003) attempted to sort out where this difference was coming from by using the "lie detecting" reputation of the polygraph machine. 96 male and 105 female undergraduates filled out sexual history surveys under one of three conditions: hooked up to a "lie detector", "anonymous", and "exposure threat", where they handed completed surveys to a peer researcher. Women's responses showed more difference between conditions than men's: women reported fewer sexual partners when they thought their responses would be read, more when they thought they'd be caught in a lie. In fact, women in the lie detector condition reported more sexual partners than the men in that condition. However, it must be noted that sex X condition effects did not reach a significant interaction (see more about subgroup analysis on 8/24/07).



The lie detector (or what the researchers called "bogus pipeline") condition is an interesting way to see how social pressure influences responses on "scientific" surveys, but I'm a little depressed that the participants rated the lie detector as accurately as they did. The students rated the machine's accuracy as 3.7 on a scale of 1 to 5 for measuring "true attitudes and feelings". There was no sex difference on this rating, or on the rating of how much the students thought the machine would pressure them to be honest. Previous studies we've looked at have indicated that women are more susceptible to social pressure, so it's not too surprising that the effect would look greater under these conditions.

I don't know if I would have used random assignment to split students among the three conditions, since the groups came out more uneven than I'm really comfortable with: bogus pipeline n = 51 (43%F), anonymous n = 61 (54%F), exposure threat n = 89 (52%F).



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Monday, March 9, 2009

Appearance Recall Accuracy

Horgan et al (2009) explore the difference between men and women on "appearance accuracy." In previous studies, women have been found to do better on tests of recall about another person's appearance (including skin and eye color, and details about clothing and accessories). In the present study, as well as in Horgan et al (2004), Horgan suggests that women's tendency to focus on people vs. things gives them an advantage over men on these tests of memory: however, there was no difference in men's and women's recall of the objects surrounding the target person. Hall and Schmid Mast (2008) tested appearance accuracy using "male-stereotypic content" and "tasks framed to favor men’s motivation", but still failed to find a scenario in which men outscored women on appearance accuracy.




Off-topic: I put a Difference Blog reader poll up on Friday. I'd really appreciate it if you took a moment to fill it out.

And now back to appearance accuracy: you know, I find it interesting that "clothing and accessories" are not considered "objects" for the purposes of dividing men's and women's fields of attention. I'm not saying that men pay as much attention to clothing as women do: not by half. But I do wonder why the "people vs. objects" dichotomy is directed at this particular task. Where is the line between an object and an accessory? Is a cell phone an accessory? What about an iPod, or a 3-ring binder? An unrelated minor complaint: one question about the office that was asked in the 2009 article was whether it was painted blue or light gray, but no information about the color-vision of the participants was reported. I have fine color vision, and I have trouble between light blue and light gray.



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Friday, March 6, 2009

A boy named Sue

Yesterday on Twitter, CaptainDomestic shared his theory of gendered name migration: "Boy names can become girl names, but not vice versa1; I'd guess 5% of men in 1900 had names that are majority female now.2". I made a couple of quick calculations3 4, but promised I'd come up with the real number today.

That number is: 1.06%. Based on the Social Security Administration's lists of most popular baby names in the 1900's and 2000's*, 1.06% of men between 1900-1910 had a name that is in in the top 1,000 most popular names for females between 2000-2007 (and not ranked higher for males). In the 1900s, 1.2% of boys had names more popular for girls in 1900s; 1.0% of girls in 1900 had names more popular for boys at the time. In the 2000s, this reversed: 1.2% of girls had "boy's names", and 1.0% of boys had "girl's names".

One of the biggest changes seems to be that women's names have had a greater move toward diversity. In the 1900's, 90.2% of men and 90.8% of women had one of the 1,000 most common names. In the years 2000-2007, this fell to 81.4% of men and 69.1% of women. Jessie, Sidney, and Guadalupe are the only names to appear on all four lists (male and female, 1900s and 2000s): Jessie went from a girl's name to a boy's name, Sidney went from boy's to girl's, and Guadalupe has always been more popular for girls.

*see limitations of the SSA data here.



So, my partner Grayskale complained (while I was playing with VLOOKUP until my eyes bled) that my operational definition of "girl's name" was weak. Well, I can't really argue with that. What makes something a "girl's name" or a "boy's name". I used the rank on the top 1,000 lists: if it was higher on the girl's list, it was a girl's name. If it appeared on the girl's list, but not the boy's list, it was a girl's name. But that doesn't address things like the question "what percentage of people named Jessie are female?", which would be an equally (if not more) valid measure. It would also be nearly impossible to calculate from the SSA site: more than twice as many women than men appear in the data from 1900.


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Thursday, March 5, 2009

Marital Stress

Nancy Henry and Tim Smith, at the University of Utah, suggest that a bad marriage may be unhealthier for the wife than for the husband (Univ. of UT P.R., 2009). While both men and women are more likely to suffer from depressive symptoms when their marriages are in trouble, men do not seem to develop "metabolic syndromes" in response, but women do. "Metabolic syndrome" is a cluster of symptoms: "hypertension, obesity around the waistline, high blood sugar, high triglycerides and low levels of HDL, which is 'good cholesterol'." These factors are tied to increased risk of heart disease, the number one killer of adult women (and men, see 2/9/09). The authors suggest that the female hormonal response to stress may be more harmful than men's stress response. Perhaps relevant to this discussion are findings by Kurdek (2005) and Schmitt and Kliegel (2006) which found no gender differences in marital satisfaction, although Schmitt and Kliegel did find higher reports of "marital stress" among women than men.



Honestly, I was expecting to find that women reported less satisfaction than men. I really was. I thought some of the "happiness gap" (9/28/07) and tendency to complain (12/1/06) would come into play. In my admittedly limited experience, I have found that female partners are more willing to bring up concerns about a relationship, and more likely to worry about them. I had expected this to be reflected in research, but it's nice to be wrong. I'm reminded of one of my favorite Jeff Murdock-isms from the defunct British sitcom, Coupling (2000-2004): "Maybe women are completely different when we're not with them. Maybe they're not cross all the time. "(IMDB)



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Wednesday, March 4, 2009

Stereotype Stigma in Mental Illness

Wirth and Bodenhausen (2009) report that the social stigma on mental illness raises the most sympathy when symptoms present counter to gender stereotypes. The experiment presented case studies of an alcoholic and a depressive to 186 "nationally representative" reviewers (recruited through random-digit dialing by Knowledge Networks). When a female case was presented with depressive symptoms, reviewers expressed more "anger and disgust" and less sympathy than when she was presented with alcoholic symptoms. The reverse was true for the male case. Reviewers were more likely to consider the case's cause biological when the symptoms were not gender stereotyped. See Wray Herbert's "Only Human" blog for more on this study.



I am not a unique snowflake. Okay, I knew that, but this study really drove it home for me. I know that I tend to express more sympathy and fellow-feeling for people when they behave counter to stereotyped role. What I didn't realize was how common this reaction is. I would have thought the unexpected would be more threatening; that people would have shown more sympathy to a case that reminded them of an example in their own lives. Come to think of it, it may be parallels in their own lives that made the stereotypical cases less sympathetic: personal hurt to the lashing out of a male alcoholic or female depressive could easily have swayed the results. Which do you think is more likely: that people dislike conformity to stereotype, or that parallels to personal experience decreased sympathy?



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Tuesday, March 3, 2009

Religious Differences

Grim and Masci (2008) says that 1.6% of Americans say they are atheists, and that men are twice as likely as women to make this claim. This is according to a survey taken by the Pew Forum on Religion and Public Life during 2007. However, new analysis of Pew's data, released last week (Pew, 2/26/09) demonstrates a gap between men and women on a multitude of religious measures, such as prayer, service attendance, and others.

Another Pew paper, the U.S. Religious Landscape Survey (2008, pdf), reports that men are also more likely to claim no specific religious affiliation than women (19.6% to 12.8%). The combined response of 16.1% unaffiliated is identical to the statistical abstract provided by the U.S. Census (2009). **

However, a closer look at the "Other" column in the "Religious Landscape" paper shows that the female advantage only applies to Christian traditions (which make up 78.4% of the survey's respondents). In every one of the "Other Religions" listed (Jewish, Muslim, Buddhist, Hindu, Other world religions, Other faiths), the percentage of men is higher, with a total of 5.2% of men and 4.2% of women identifying with one of these categories.



I used to be fairly active in the neopaganism movement, since that was the religion I was raised in. One of the movement that I really believed in (and still believe in) was the call to use the umbrella term "Pagan" on the census and other surveys, so as to appear as a distinct category. "Stand up and be counted," and so on. I last thought about this in probably 1995 or so. I just noticed that "New Age" religions make up 0.4% of the U.S. population, according to the 2009 Census abstract. In 1990, no results for "Pagans" were reported in the census; in 2001, 140,000 people answered "Pagan".

**edit 2:42pm: I just noticed that the US Census data includes Atheist in Unaffiliated, which Pew didn't. So the 16.1% is not an identical number.

See also:
Mental Health and Religious Attendance 1/22/08
Very superstitious 3/2/07
Differences in Religiosity Pt 1 1/29/07 and Pt 2 1/30/07


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Monday, March 2, 2009

Financial Independence

A Reuters Synovate survey asked 4,500 women (and an equal number of men) about their financial responsibility. According to the Reuters story (2009), over half of all respondents believed women were more financially responsible than men. The Synovate website (2009) gives more detail: 61% of women and 40% of men thought women were more responsible (meaning the actual division is basically equal).

Pahl (2009) suggests that couples in the United Kingdom "and elsewhere" are becoming less financially intertwined, which in some cases may indicate independence, but for others, may breed inequality. The Reuters Synovate survey found that 41% of women defined financial independence as not being dependent on a partner for money, while 30% defined it as living debt-free. 58% of the female respondents thought they were financially independent. Jay MacDonald (2005), writing for BankRate, suggests that the main difference between men's and women's spending habits is timeline: women have a "now-money orientation" while men have a "future-money orientation".




I'm probably overly cautious about keeping my finances separate from my partner's. Despite having cohabited with partners pretty consistently since 1996, I have never had a joint checking account. I've only purchased one large household item jointly (and ended up getting "bought out" of my share a few months later), and my partner and I keep fairly detailed spreadsheets regarding who has covered which household expenses (pretty much everything except food). Even so, my biggest worry is making sure I'm pulling my own weight. I do think transition changed my outlook on money, but not because of social role or hormones. My outlook changed because transition is expensive: I had to plan for big expenditures.

see also: Bankruptcy, 1/12/09; Sexism in Lending, 11/10/08.



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