Bigger Doesn't Mean Better: Women's Brains Are Smaller But More Efficient Than Male Brains
Women have smaller but more efficient brains than men, according to a new study.
Based on the latest findings, published in the March-April 2013 edition of the scientific journal Intelligence, bigger doesn't always mean better. The study found that even though a woman's brain is slightly smaller than a man's, her brain uses less energy and fewer brain cells to achieve the same or even better results
Researchers explain that while men have more neurons, women have more connections between their neurons, enabling them to think quicker despite having less grey matter.
Neuroscientists from the University of California and Autonomous University of Madrid wanted to see why women, who typically possess brains that are 8 percent smaller than those of men, were just as intelligent as their male counterparts. Researchers focused on the section of the brain called the hippocampus, a major component of the human brain that plays an essential role in memory consolidation and emotions.
Previous studies found that men with larger hippocampuses had more neurons and were more intelligent. However, studies on women found that a larger hippocampus, which was still typically smaller than men's, did not predict greater intelligence. Surprisingly, researchers found that a smaller hippocampus in women suggested greater intelligence.
Researches analyzed the brains of 59 women and 45 men between the ages of 18 and 27. Participants completed 21 tasks measuring abstract, verbal, and spatial intelligence, along with working memory, executive control, attention, and processing speed.
Like previous findings, researcher found that women were better at inductive reasoning and tracking a changing situation, while men were better at spatial reasoning.
"After permutation tests corrected for multiple comparisons across vertices), significant relationships were found for spatial intelligence, spatial working memory, and spatial executive control," researchers wrote.
"Interactions with sex revealed significant relationships with the general factor of intelligence, along with abstract and spatial intelligence," they added.
However, researchers said that the findings suggest that female brains were more efficient than male brains.
The study results indicated that the correlation between hippocampus size and intelligence was mainly positive for men and negative for women, which according to researchers "support the efficiency hypothesis in women".
"At this structural level, females might show greater efficiency requiring less neural material for achieving behavioral results on a par with males," researchers concluded.
Researchers noted that verbal intelligence, attention, and processing speed were not significantly related to hippocampal structural differences.