Using the brain scans of 46,034 people, a new study has sought to identify how brain activity differs between men and women, particularly in regards to how psychiatric conditions manifest themselves.
As reported in the Journal of Alzheimer's Disease, the results showed that healthy women had significantly more activity in many more areas of the brain than men. However, the healthy men were shown to have notably higher levels of activity in certain areas of the brain.
“This is a very important study to help understand gender-based brain differences," lead author and psychiatrist Daniel G Amen, founder of the Amen Clinic, explained in a statement. "The quantifiable differences we identified between men and women are important for understanding gender-based risk for brain disorders such as Alzheimer's disease."
The researchers looked at brain scans imaged using the SPECT (single photon emission computed tomography) technique to measure blood flow, which indicates brain activity.
According to the study, this technique showed that women had a more active prefrontal cortex, the part of the brain associated with impulse control and focus, as well as the limbic system, associated with mood and anxiety levels. They say this could explain why women tend to exhibit greater empathy, intuition, and self-control. On the other hand, the visual and coordination centers of the brain were shown to be more active in men.
Before you go jumping to conclusions, there are a few things to consider with this study. The overwhelming majority of the samples had some kind of psychiatric condition, such as brain trauma, bipolar disorders, mood disorders, schizophrenia/psychotic disorders, or attention deficit hyperactivity disorder (ADHD). Out of the thousands of scans, just over 115 were completely healthy. This means the sample as a whole was not totally representative of the normal population, even though the study claims "results demonstrated significant gender differences in a healthy and clinical population."
On another note, Amen's application of some SPECT imaging practices has previously come under skepticism by others in the field.
Nevertheless, the researchers said their findings could help explain why men and women are more vulnerable to certain psychiatric conditions. For example, the study authors say women are more at risk of Alzheimer’s disease, depression, anxiety disorders, and eating disorders. Men, however, have much higher instances of ADHD.
“Precisely defining the physiological and structural basis of gender differences in brain function will illuminate Alzheimer’s disease and understanding our partners,” added Dr George Perry, Editor-in-Chief of the Journal of Alzheimer’s Disease.