A just published paper says that during puberty blood flow levels decrease in boys while they increase in the case of girls. The finding may explain many sex specific psychiatric disorders, such as depression, anxiety and schizophrenia.
It was well-known that adult women have higher blood flow than men. But when does this gap begin to form? Researchers, led by Dr. Theodore Satterthwaite of the Perelman School of Medicine at the University of Pennsylvania appear to have an answer to that question.
Based on their study which might open new approaches to dealing with sex-linked psychological disorders, the researchers point out that blood levels decrease the same way in both sexes before puberty. But during puberty, the levels move in opposite directions: they increase in girls and drop in boys. Although previous studies had proved that CBF or cerebral blood flow declines during childhood, there was little to show the effects of puberty on brain physiology.
Dr Satterthwaite’s team used arterial spin labelled MRI to image the brains of over 900 young people between the ages of 8 and 22 years old to arrive at their findings which indicate sex-specific predispositions to certain psychiatric disorders.
The study shows that there are age-related differences in both the amount and location of blood flow in males and females. The CBF levels continue to decline in males through adolescence and increase in women, because of which females end up with significantly higher CBF than males post adolescence, particularly in areas of the brain involved in social behaviors and emotion regulation. These differences are probably the reason why females consistently out-perform men on social cognition tasks.
Commenting on their results, Dr. Satterthwaite says: “The findings will aid our understanding of normal neurodevelopment and eventually make it possible for us to create ‘growth charts’ for brain development in kids. Our findings merely prove what every parent knows: boys and girls grow differently. This applies to the brain as well.”
With such growth charts doctors may be able to identify abnormal brain development much before it leads to major mental illness.