In research published in the journal Cell Stem Cell, scientists at Columbia University Vagelos College of Physicians and Surgeons present the most definitive evidence to date that the human brain makes new neurons throughout life.
Previous studies of animal brains have led many neuroscientists to conclude that the capacity for neurogenesis, or the production of new neurons, declines with age and virtually ceases in the mature brain. “In mice, researchers have shown that neurogenesis drops pretty dramatically after middle age,” said the study’s lead author Maura Boldrini, MD, PhD, a research scientist in psychiatry and a member of the Columbia Stem Cell Initiative. A recent study of human brains was also unable to find new neurons in adult brains.
The brain’s hippocampus, which is responsible for memory and learning, has been a major focus of studies on neurogenesis and stem cell biology. Although neuroimaging studies of humans show that continued growth in this structure occurs in adulthood, many scientists have argued that this represents existing neurons growing larger, or an expansion of blood vessels or other internal support structures, rather than the addition of new neurons. To address the question, investigators dissected and examined a representative sample of human hippocampi from healthy people of different ages after they died. Continue reading