FLICKR, _DJ_The human cerebral cortex experiences a burst of growth late in fetal development thanks to the expansion and migration of progenitor cells that ultimately form excitatory neurons. For a fully functional brain, in addition to excitatory neurons, inhibitory ones (called interneurons) are also necessary. Yet scientists have not been able to account for the increase in inhibitory neurons that occurs after birth. Now, in a paper published today (October 6) in Science, researchers from the University of California, San Francisco (UCSF), have shown that there is a reserve of young neurons that continue to migrate and integrate into the frontal lobes of infants.
“It was thought previously that addition of new neurons to the human cortex [mostly] happens only during fetal development. This new study shows that young neurons continue to migrate on a large scale into the cerebral cortex of infants,” Benedikt Berninger, who studies brain development at the Johannes Gutenberg University of Mainz, Germany, and was not involved in the work, wrote in an email to The Scientist. “This implies that experience during the first few months could affect this migration and thereby contribute to brain plasticity.”
Aside from the migration of neurons into the olfactory bulb in infants, “this is the first time anyone has been able to catch neurons in the act of moving into the cortex,” said New York University neuroscientist Gord Fishell ...
