The brain's hippocampus stops producing new cells (neurons) by age 13, according to a new study. It had been thought that the hippocampus -- which plays a major role in learning and memory -- generates new neurons throughout adulthood, CNN reported. Arturo Alvarez-Buylla, professor of neurological surgery at the University of California, and colleagues analyzed 59 hippocampus tissue samples ranging from fetuses to adults. Their study was published in the journal Nature. The study is important, according to Jason Snyder, assistant professor, Department of Psychology, University of British Columbia, Canada. He was not involved in the study but wrote an accompanying editorial in the journal. "It provides strong evidence that the human brain's ability to produce newborn neurons in the hippocampus (a brain region involved in memory formation) is limited as we get older," Snyder wrote in an email to CNN. The study also points to new areas of investigation. "If we can understand how neural precursor cells work, we may be able to use them to replace neurons that have died," Snyder told CNN. Source