differenceblog, posts by tag: hands - LiveJournal

What does your handshake say about you? Chaplin et al (2000) had 2 males and 2 females rate the handshakes and first impressions of 112 participants (57% women). These predictions were compared to actual results on several personality inventories. A firmer handshake was related to openness (imagination, creativity) in women, but a less firm handshake was related to openness in men. Chaplin also found that more "open" women made a better first impression, while more open men made a slightly worse one.

Men's handshakes were "firmer" than women's, based on Chaplin's "Firm Handshake Composite", an aggregate score based on "strength, vigor, duration, eye contact, and completeness of grip." Gender was unrelated to a positive first impression based on the "First Impression Composite" (aggregated rater predictions of "extraversion, conscientiousness, agreeableness, emotional stability, openness, emotional expression, outgoingness, and positive affect").

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I shake hands. I have freaked out small children by trying to shake their hands. Apparently one doesn't do this with small children. I don't remember when hand-shaking became part of the standard introduction protocol for me, but I remember noticing that it had happened. It happened at some point during college, so I was still a woman at the time. Judith Kleinfeld's (2008) article about Chaplin's research pointed out a gender difference in ettiquette that I'd missed. A man shouldn't initiate a handshake with a woman unless she puts out her hand first, because it's uninvited physical contact. I hadn't thought of that. I wonder if I've been pressing myself on female colleagues inappropriately.

I haven't asked this in a while, but if you're enjoying DifferenceBlog, I'd really appreciate a link in your LJ.

Twin studies are a scientist and media favorite. Because twins share the womb, their pre-natal environment is identical. Their upbringing, in most cases, can also be assumed to be similar -- even more so than for non-twin siblings. However, most twin studies focus on identical twins, in order to control for genetic differences as well. But in the study of gender differences, opposite-sex twins (necessarily fraternal) may be even more enlightening.

Procopio and Marriott (2007) found that males with a female twin did not have a different risk of developing anorexia nervosa than their twin sisters. Resnick et al (1993) (in a re-analysis of data collected in the 1970's) demonstrated increased sensation-seeking behavior in women with a male twin. Van Anders et al (2005) may have an explanation: their study of finger-length ratios suggests that hormones (probably androgens) transfer between twins prenatally. In contrast, Elkadi et al (1999) found no increased incidence of left-handedness (which they claim would indicate androgen transfer) in women with male twins.

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I always wanted to be a twin, growing up. I don't have a good reason. It just seemed neat. I wasn't particularly sold on a twin of either gender, although I did think an identical twin would be kind of cool. Then again, I also thought having an identical twin would give me psychic powers.

The thing I find especially encouraging about Procopio and Marriott is that they are looking at a way in which men are more like women, rather than the ways women are more like men. It gets really exhausting reading study after study where men are the baseline condition. The male baseline is evident in all the other studies cited today.

How much of our brain's gender is visible in our hands? Sanders and Waters (2001) found that performance on sexually dimorphic tasks was predicted not by sex, but by finger ridge count (dermatoglyphics). Most people have more ridges on their right fingertips than their left. "Male-favouring" tasks were better performed by people with more right ridges. "Female-favouring" tasks were better performed with more on their left fingers. Kimura and Carson (1993) found that the left-asymmetry was more prevalent in women and homosexual men than in the general population. Mustanski et al (2002) (with everyone's favorite "sex expert" J. Michael Bailey contributing) found that left-handedness was more prevalent in homosexual women than heterosexual women, but not in homosexual men versus heterosexual men. Mustanski found no association between dermatoglyphic asymmetry and sexual orientation. Williams et al (2000) is one of many sources to report a sexual dimorphism in finger length ratios that may reflect sexual orientation as well (see also: Rahman and Wilson, 2003, Brown et al (2002)).

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Are you looking at your hands yet? In my previous life, I read palms a little. I even volunteered as a palm reader in a charity carnival in junior high. At that point, I was taking my cues largely from the patterns I learned from my mother and from books on palmistry. After college, I still read palms -- but at that point I was trading the readings for free drinks. I also learned to do the readings more as a "warm read" -- taking cues from people's reactions more than from anything I saw on their hands.