School of Neuroscience Innovators Seminar Series 

Shawn Sorrells, Ph.D., Department of Neuroscience, University of Pittsburgh

  • Wednesday, February 5, 2020 
  • 11:00 am – 12:00pm
  • Fralin Auditorium

Childhood and adolescence are key times for emotional development in humans, and brain regions critical to emotional learning like the amygdala and hippocampus grow significantly in size during these ages. The controversy surrounding the presence of adult neurogenesis in the human hippocampus has been rekindled following my finding that a proliferative niche of neural stem cells does not coalesce in the human dentate gyrus, in contrast to other species including non- human primates. This was quickly countered by other studies showing persistent expression of markers of immature neurons in even the aged human hippocampus. Interestingly, most of the labeled neurons in these studies have mature morphology, suggesting they may have been born much earlier but undergo an incredibly protracted maturation process. This might sound unlikely, except this exact process appears to be happening in the human amygdala. In many of the same human brains that did not contain dividing neural stem cells or young neurons in the hippocampus, the amygdala contained a large population of neurons with immature morphology, gene expression patterns, and ultrastructural features. Remarkably, these neurons matured into excitatory neurons across human life with their development accelerating in adolescence. These cells may also reveal basic timing mechanisms that dictate the speed of neuronal development, which takes years for these unique amygdala neurons, months during normal gestation in primates, and only days to weeks in rodents. 

For more information, contact Keaton Unroe.