I just finished reading an article in which Dr Justin Rhodes PhD, an assistant professor of psychology and neuroscience at the University of Illinois states that a person can continue to make new brain cells throughout their lifetime and that exercise may help stimulate the production of new brain cells.This process is called Neurogenisis
The kicker though, and what struck me as an unlikely coincidence, is that Neurogenisis takes place in the Olfactory bulb and the Hipocampus of the brain.
The Olfactory bulb, is among other things the center for processing the sense of smell!
Loss of sense of smell is often the first symptom of the onset of Parkinsons!
It still couldn't hurt to exercise...besides the other benefits, the studies claim that in lab rats both young and aged, the ones on the exercise regimen had twice as many brain cells as their sedentary relatives.