The Male Brain (21 page)

about objects and impersonal topics
: Pennebaker 2004.

 

talk much about personal topics
: Newman 2008.

brain at all before puberty
: Burnett 2009 found that, unlike basic emotions (such as disgust and fear), social emotions (such as guilt and embarrassment) require the representation of another's mental states; and during this transition, teens activated a different brain area for social versus basic emotions, while adults or children did not. See McClure 2004 for more on responses in the teen versus the adult brain.

for social approval or disapproval
: Klucharev 2009 found that conflict with peer-group opinion triggered a brain response in the RCZ. They conclude that social-group norms evoke conformity via activity of the RCZ and ventral striatum. Jocham 2009 found that when an action leads to an unfavorable outcome, behavior needs to be adjusted and that in the human brain the RCZ is particularly responsive to performance errors and social disapproval. For more on the brain and social approval, see Tzur 2009, Yaniv 2009, and Behrns 2009.

process of a massive recalibration
: For more on the brain effects of social exclusion and the distress of peer rejection during adolescence, see Masten 2009. For more on brain recalibration due to social emotions, such as embarrassment and guilt, see Burnett 2009.

by their clans or tribes
: Freeman 2009a found culture shapes the brain's response.

score and regained some respect
: Stanton 2009 found that high testosterone levels are associated with dominance behavior and pursuit of status in men, and that men's testosterone levels rise after winning dominance contests. This positive feedback to the brain primes future dominance behavior. For more on hormones and social status in males, see Sapolsky 1986 and 2005, Becker 2008b, Hermans 2006 and 2007 and 2008, Rubinow 2005, Van Honk 2005 and 2007, and Viau 2002.

in front of his peers
: For more on the brain, social value, social learning, and self-confidence, see Behrens 2008 and Eme 2007.

establish and maintain social hierarchy
: For more on the brain, social hierarchy, dominance, and subordination, see Freeman 2009. For more on teen boys' behavior and hormones, see Olweus 1988 and Archer 2006.
and not afraid to fight
: Sell 2009 found that males begin to show displays of hostile intent, such as angry facial expressions, in the teen years, and that males learn to quickly assess the strength and fighting spirit of other males just by looking at their faces.

become hard to live with
: Olweus 1980 and 1988 found that teen boys have increased irritability.

his team couldn't lose
: See Becker 2008a for more on the male brain and sex differences in excitement and dopamine systems. Salvador 1987, 2003, and 2005 found that during competition, a male's testosterone increases and, depending on the outcome and the importance of the event for the male, remains high for winners and drops for losers. Suay 1999 studied judo competitors. In those athletes larger increases in testosterone were highly correlated with looking angry while fighting, responding to a challenge, and being a violent competitor. For more on competition, brain, and testosterone, see Gatzke-Kopp 2009, Kahnt 2009, Sallet 2009, Kraemer 2004, and Berman 1993.

losing, even in sports spectators
: Bernhardt 1998 found that even the vicarious experience of being a fan whose team wins--leads testosterone levels.
winning--e.g.,

to increased

in favor of their own
: Weisfeld 1999. See Levinson 1979 for more on psychological stages of development in adolescent males.

seek autonomy from his parents
: Weisfeld 1999 and 2003. Fischer 2007 found that a high level of gender-role conflict in adult men was associated with parents' overprotection in teen years.

they strike out on their own with bravado
: Spear 2004.

 

new ideas in every generation
: Spear 2004 and Nelson 2005.

willing to do risky things
: Nelson 2005. Steinberg 2007 found that adolescents and college-age individuals take more risks than children or adults do, which is reflected in statistics on automobile crashes, binge drinking, contraceptive use, and crime.

consequences of unsafe, impulsive choices
: Steinberg 2007. Teicher 2000 found that the part of the brain that allows and encourages us to delay gratification and inhibit impulsive action--the PFC--won't be finished until later in the teen years and that it develops even later in boys' brains than in girls'.

in a video driving game
: Steinberg 2004 found that the presence of peers more than doubled the number of risks teenagers took in a video driving game. Dahl 2008 says that sleep deprivation is rampant among adolescents and that the consequences of insufficient sleep (sleepiness, lapses in attention, susceptibility to aggression, and synergy with alcohol) appear to contribute significantly to driving risks in teens.
know what they're doing
: Eaton 2008 found that in the United States, 72 percent of all deaths among persons age 10-24 result from four causes: motor-vehicle crashes, other unintentional injuries, homicide, and suicide. The 2007 national Youth Risk Behavior Survey (YRBS) indicated that many high-school students engaged in behaviors that increased their likelihood of death from these four causes.

biologically ready to handle independence
: Doremus-Fitzwater 2010 found that biological changes in the brain's motivational and increase teens' peer-directed taking, novelty seeking, and drug and alcohol use relative to adults. For more on how teens' sleep deprivation influences risky peer interactions, see Dahl 2008. reward-related regions

social interactions, risk

 

prefrontal cortex (PFC)--is like a brake
: Steinberg 2004 and 2007.

 

boys until their early twenties:
Giedd 1996 and 2009.

mother's body, but also by her smell
: Savic 2001 and Weisfeld 2003 found that the odor of genetically related family members is not romantically attractive. For more on MHC genes and odorous attraction, see Garver-Apgar 2006, Wedekind 1995, and Yamazaki 2007.

to have fleeting sexual fantasies
: Campbell 2005 studied schoolboys age 12-18. The study found spontaneous nocturnal emission, secondary sexual characteristics, and salivary testosterone correlated with age at first sexual fantasies, noncoital sexual behavior, and coitus. They found first erection at an average age of 10.75 years, first sexual fantasy at 12.66 years, first spontaneous nocturnal emission at 13.02 years, and adult levels of blood testosterone at 17.2 years. Carlier 1985 found that boys' testicle size correlated best with first ejaculation.

when boys begin frequent masturbation
: Korkmaz 2008 found that over 90 percent of 16-year-old boys masturbated and 98 percent reported that they liked it and thought it was natural. However, some felt guilt, fear of harming one's body, or shame. Some boys felt sexually inadequate when they compared themselves with their peers, feeling they were not as attractive to girls. For more on sexual behavior in teen boys, see Giles 2006, Auslander 2005, and Browning 2000.

to three times a day
: Tanagho 2000.

less than one time per day
: Korkmaz 2008. Gerressu 2008a found that 95 percent of men and 71 percent of women masturbated. And one consistency across all studies was the large gender difference in the prevalence and frequency of masturbation--both being much greater in males. For more on sexual frequency in males and females, see Kontula 2002, Hyde 2005, Dekker 2002, Pinkerton 2002, Langstrom 2006, Giles 2006, and Laumann 1999b.

at the first opportunity
: Tanagho 2000.

finally came to "do it"
: Adolescents are faced with many developmental tasks related to sexuality, such as forming romantic relationships and developing their sexual identities. Almost half will engage in vaginal sexual intercourse by the end of high school. For more on puberty and sexual development, see Eaton 2008 and Auslander 2005.

THREE: THE MATING BRAIN: LOVE AND LUST

The Mating Brain: Love and Lust
: For a review on similarities and differences in the mate preferences and choices of women and men, see Geary 2004 and Young 2008.

lit up like a slot machine
: For more on brain circuits for male courtship behaviors, see Pfaff 2002, Fernandez-Guasti 2000, Wu 2009, Maner 2007b, and Manoli 2006.

of his ancient mating brain
: Voraceck 2006 found that the ultimate goal of female physical attractiveness is to elicit male sexual arousal. They found that males focused more on waist-to-hip ratio in women they saw moving and more on bust size in women who were stationary. In humans, the nucleus of the preoptic area of the hypothalamus is two to two and a half times larger in the male brain compared with the female. And Welling 2008 found that changes in testosterone levels contribute to the strength of men's attraction to femininity in women.

in men across all cultures
: Singh 2002.

mate-detection circuit was visual
: Tsujimura 2009 found that in the non-intercourse video clip, gaze time for the face and body of the actress was significantly longer among men than among women.

mating brain read Nicole right
: Amador 2005 found that both sexes place high value on traits like dependable character, emotional stability/maturity, and pleasing disposition, as well as mutual attraction and love. Women in the study placed industrious character, and good financial prospects. Men cared more about the woman's fitness and good health, good cooking/ housekeeping skills, and good looks.
higher emphasis on ambitious/ similar educational background,

cute and looked harmless enough
: Maner 2008 and Shoup 2008. For more on mating judgments of men versus women, see Gangestad 1993 and 2000.

cues as Ryan and Nicole
: Eibl-Eibesfeldt 1972.

not out of his league
: Bateson 2005 and Alpern 2005 found that both men and women become less choosy over time, as the highest-ranking and most fit and attractive individuals pair off first. This means that for a male to be chosen by her as the best, all he has to do is outshine the other males he is being compared with on the specific characteristics she is focusing on.

"I'm here to watch you"
: O'Hair 1987 and Farrow 2003.

 

wrong with meeting those expectations
: O'Hair 1987 and Haselton 2005.

with the highest-pitched voices
: Apicella 2009. Sokhi 2005 found that female and male voices activate different regions of the male brain. Hughes 2008 and Pipitone 2008 found that a woman's voice attractiveness varies across the menstrual cycle.

go weak in the knees
: And Roney 2008 found that women are more attracted to men's masculine characteristics, like jutting jaw and large muscles, during the ovulatory phase of the menstrual cycle.

potentially a good genetic match
: Savic 2001b found that men are most attracted to the scent of women who are genetically Lundstrom hormonal birth control do not make the same pheromones or have the ovulatory-phase rise in testosterone derivatives like androstenedione that stimulate the sweat glands to produce those feminine "come-hither" pheromones.
different from them. And according to 2006, women who are on the "pill" or

give birth to sickly offspring
: Alvarez 2009.

best to each other
: Wedekind 1995. Yamazaki 2007 found that dissimilar gene-type MHC emits special body odors that underlie mate choice and familial recognition, which helps make sure that inbreeding with parents and siblings does not occur. For more on brain responses to pheromones, see Hummer 2010, Mujica-Parodi 2009, and Prehn-Kristensen 2009.

and not even known why
: Li 2007 says that people's odors can increase or decrease their likeability rating. Furthermore, according to Berglund 2006 and Sergeant 2007, gay males' and gay females' brains respond positively to same-sex pheromones. They dislike those odors of the opposite sex. For more on mating and pheromones, see Savic 2001a and 2009 and Zaviacic 2009.

about hygiene; it's about genes
: Weisfeld 2003 and Olsson 2006. Havlicek 2009b found that olfactory and visual channels may work in a complementary way in mate attraction to achieve an optimal level of genetic variability.

could talk to her about
: Keverne 2007 suggests that a male's ability to find a fertile mate requires some serious strategic maneuvering and that for human males, these reproductive strategies are complex and embedded in the social structure and hierarchies of society. So success in human males usually depends more on intelligent behavior than on hormones or odors.

tension between them was palpable
: Roney 2007 found that a man's testosterone goes up just from talking to a woman.

secretly sent to their brains
: Gallup 2008 and Hughes 2007 found that kissing is a mate-assessment device. Wyart 2007 found that testosterone and its metabolites are found in male saliva, semen, and sweat--and they smell, and perhaps taste, delicious to a woman when she is ovulating. While females find the masculine odor attractive, heterosexual males dislike it. For more on pheromones and mating, see Bensafi 2003 and Walter 2008.