Invitation to Psychology

144 Chapter 4 Neurons, Hormones, and the Brain

and females have shown different patterns of brain

activity while they were doing something or while

an ability was being tested, yet the sexes have

not actually differed in the behavior or ability in

question (Fine, 2010). If the behavioral differ-

ence you are interested in doesn’t exist, whatever

does it mean if you find a brain difference? One

MRI study of men and women with equivalent IQ

scores found that women’s brains had more white-

matter areas related to intelligence, whereas men’s

had more gray-matter areas related to intelligence

(Haier et al., 2005). That’s surely an interesting

finding for researchers, yet it shouldn’t obscure

the larger fact that the sexes do not differ in over-

all intelligence.

3

Sex differences in the brain do not account

for the fact that behavior depends on the situ-

ation. Consider empathy, a skill central to the

female stereotype. On self-report questionnaires,

women are more likely than men to describe

themselves as being high in empathy. But what

people say about themselves is often unrelated

to how they actually behave in various situa-

tions. When we hear that women are hardwired

to be empathic, therefore, we need to ask, which

women? Under what circumstances? Empathy

toward whom? Women are not more empathic

than men are toward people they don’t like,

whether family members they’re fighting with

or their country’s enemies. Over and over, if you

watch what people do rather than what they say

they would do, and vary the situations in which

they do it, gender differences fade (Fine, 2010;

Jordan-Young, 2010).

activity in the right amygdala, but in women, bet-

ter memory is associated with the left amygdala

(Cahill et al., 2004).

Is your own male or female brain spinning

yet? The bottom line is that some average sex dif-

Psychology in the News

do exist. But we are

still left with our sec-

ond question: What

do the differences mean

for the behavior or per-

sonality traits of men

and women in ordi-

nary life? When you hear or read popular accounts

of “sex and the brain,” keep these cautions in mind:

1

Many supposed gender differences in intuition,

abilities, and traits are stereotypes; they mis-

lead, because the overlap between the sexes is often

greater than the difference between them. Even

when gender differences are statistically signifi-

cant, they are often quite small in practical terms.

Some supposed differences, on closer inspection,

even disappear. Are women more talkative than

men, as many pop-psych books about the sexes as-

sert? To test this assumption, psychologists wired

up a sample of men and women with voice record-

ers that tracked their conversations while they

went about their daily lives. The sexes did not

differ in the number of words spoken; women and

men alike used about 16,000 words per day on av-

erage, with large individual differences among the

participants (Mehl et al., 2007).

2

a brain difference does not necessarily produce

a difference in behavior. In many studies, males

About Sex Differences

in the Brain

Cartoons like this one make most people laugh because men and women do differ, on average,

in things like “love of shopping” and “power-tool adoration.” But what does the research show

about sex differences in the brain? And what do they mean for how people behave in real life?

Thinking

CriTiCally

Jennifer K. Berman