Gender & Brains
While watching the same emotionally arousing event, different parts of women’s and men’s brains light up.
Larry Cahill has scanned the brains of men and women while they watched emotionally arousing events. The results show that typically for men only the right amygdala is activated, whereas in women, the left amygdala is activated. Previous research suggests that the right brain processes the general gist of events while the left side focuses on the details. This split could account for discrepancies between the way men and women recall emotional fights or events.
Imaging studies published in Nature indicate that in women, neurons on both sides of the brain are activated when they are listening, while in men, neurons on only one side of the brain are activated. When negotiating a virtual reality maze, men use both the left and right hippocampus for the task. To accomplish the same task, women use the right hippocampus and the right prefrontal cortex.
Rutgers University’s Helen Fisher conducts research on what men’s and women’s brains look like when they fall in love. For men, the most active regions of the brain are related to visual stimuli and penile erection. Whereas with women, several regions affiliated with emotions and memory recall become active.
According to Deborah Blum, author of the book, Sex on the Brain: The Biological Differences Between Men & Women, behavioral gender differences can be traced back to the different demands of being a sperm producer versus being an egg maker. Fisher’s theory is that in order to determine who will be a good mate, females must remember details of personality and behavior to determine what kind of provider their partners will be. The romantic love experienced by women is intended to start a mating process and ensure the female is not abandoned in the early years of raising children.
It has been suggested that testosterone, which runs high in men and tends to spike in times of challenge, propels a quick aggressive response. In women, on the other hand, oxytocin provides for lactation and it has been associated with bonding and nurturing behavior. These hormones act upon the brain in distinctive ways and suggest why men and women develop different parts of their brains, at different rates and at different times. This field of research is complicated because the brain is plastic and easily influenced by environment and circumstance.
Men and women also may respond to illness in dissimilar ways. Research shows that men and women require different dosages and kinds of drugs to treat schizophrenia, Alzheimer’s disease and depression.
“He Said, She Said,” by Polly Hanson and Maggie Villiger, Scientific American