Male brains tend to have a slightly higher proportion of white matter, whereas those of females have a higher proportion of grey matter in most parts of the cerebral cortex. Consequently, the cortex is slightly thicker in women's brains than in men's and, according to several studies, is slightly more convoluted as well. (http://www.theguardian.com/science/neurophilosophy/2013/oct/06/male-brain-versus-female-brain)

Males have 6.5 times more gray matter related to cognition and intelligence (gray matter processes information locally in the brain). Females have 10 times more white matter related to cognition and intelligence (white matter connects information between different brain processing centers). (Gurian, Michael, PhD., and Barbra Annis. Leadership and the Sexes. NY: Jossey-Bass, 2007. p 32-33)

Gray matter, located in a quarter-inch layer at the surface of the brain, is basically responsible for intelligence. Blood flows faster through gray matter than through any other brain tissue. By measuring the rate of blood flow, researchers determined that left-handers (male or female) and females have more gray matter than right-handed males. (Stump, Jane Barr, PhD. What’s the Difference? How Men and Women Compare. NY: William Morrow and Company, Inc., 1985. p 86-87)

Males have about 4 billion more brain cells, but women have more gray matter and in terms of general intelligence, tested 3% higher than men. (Pease, Barbara and Allan. Why Men Don’t Listen and Women Can’t Read Maps. NY: Broadway Books, 1998. p 46-47)

Gray matter, located in a quarter-inch layer at the surface of the brain, is basically responsible for intelligence. Blood flows faster through gray matter than through any other brain tissue. By measuring the rate of blood flow, researchers determined that left-handers (male or female) and females have more gray matter than right-handed males. (Stump, Jane Barr, PhD. What’s the Difference? How Men and Women Compare. NY: William Morrow and Company, Inc., 1985. p 86-87)

Males have about 4 billion more brain cells but women have more gray matter. (Pease, Barbara and Allan. Why Men Don’t Listen and Women Can’t Read Maps. NY: Broadway Books, 1998. p 46-47)