The Effect of Testerone on Human Brain Activity

Testosterone is the main ingredient in 'masculinizing' the brain and, ultimately, the body. In puberty, testosterone further develops physical and sexual characteristics. But it also has much effect on the brain and its activity, and is the cause of most of the physical and neurological differences between men and women.

Birth, Puberty, and Beyond

• Testosterone directs the brain to tell the rest of the body to differentiate into proper sexual organs begin growth of facial and pubic hair, along with other changes in puberty. Testosterone is also important in the development and functioning of the ovaries in women, as well as bone strength and libido.

Size

• In males, testosterone is responsible for larger brain size. Women, however, have a much larger corpus callosum and have more nerve connections between brain cells. Men may have a larger brain, but there is a decreased connection between hemispheres.

Functions

• Studies suggest testosterone helps with cognitive functions such as attention, memory, and spatial ability. Low testosterone levels may be a factor in declining cognitive abilities, and even perhaps in the onset of Alzheimer's or other dementia.

Behavior

• Testosterone is not directly shown to affect moods, and there is a weak correlation between testosterone and aggression. Aggressive behavior and mood disorders have, in fact, been found more often in individuals with low or extremely high levels of testosterone. Testosterone is a hormone of confidence and assertion, but not directly aggression.

Brain Cells and Steroids

• High levels of testosterone, mainly from steroids, can kill off brain cells. Large amounts of testosterone can lead to hyper-excitability, suicidal thoughts, and highly aggressive behavior. If normal levels are interrupted, everything can be thrown off kilter, from moods to behavior to memory. High concentrations of testosterone kill the cells' membrane stability and make them more vulnerable. Over-stimulation of cell death, a natural occurrence, can lead to neurological illnesses like Alzheimer's and Huntington disease.