Study Shows Brain Cell Growth Diminishes Even Before Old Age

A recent study by Princeton University found that even in adulthood, the mind's growth slows down. Princeton University's findings were based on their study of the brains of adult monkeys.

Neuroscientists from Princeton University studied marmoset monkeys and found that when marmoset monkeys reach adulthood, the growth rate of neural cells in the hippocampus, the region of the brain associated with learning and memory, have declined. The decrease of new cell growth is what scientist calls as neurogenesis and while this phenomenon has been observed in the brains of rodents, this is the first time that neurogenesis has been noted in primates.

The Princeton researchers studied Marmoset monkeys which are commonly found in Central and South America. Marmosets reach sexual maturity around 18 months and show signs of old age at the age of 8 years. Signs of old age in marmosets include dementia and arthritis. The Princeton researchers examined 17 marmosets belonging to both genders with ages ranging from 18 months and 7 years of age and examined their neural cell growth. The Princeton team found that young adult marmosets have vigorous new cell growth in the Hippocampus but older marmosets have fewer new brains cells.

According to Elizabeth Gould, a team member of the research team, the findings indicate that neurogenesis continues long past puberty and does not stop entirely and that it could be stimulated with experience. Though the findings that the brain shows a decrease in neurogenesis even before the onset of old age seems like bad news, Gould said that these were encouraging since it implies that researchers may find a way to stimulate the human brain to generate neural cells more rapidly.

Gould further stated that there were theories that suggest the brains in primates, like monkeys and humans, don't undergo changes in the brain structure once they reach adulthood. Their findings however shoes that primate brains undergoes structural reorganization over time. To stimulate brain cell growth, researchers believe that the methods used to stimulate neural growth in rats, i.e. socializing and exercising, may also work in primates. Gould believes that their discovery is useful since it adds to the list of changes that have been noted in the brains of primates and rodents which could mean that what scientists discover about rodent brains, the most commonly used creatures in neuroscience experiments, can also be applied to primates.

Gould however cautioned that it would still be premature to draw hard conclusions about the human brain based on their findings. The study only suggests that methods to maintain the mind's flexibility do exist.

SOURCE:

Princeton University, "Brain cell growth diminishes long before old age strikes, animal study shows". Princeton.edu.