New neurons help us to remember fear

June 15, 2011

Newly born nerve cells (green) colocalizing with a neuronal marker that indicates immature nerve cells (red); astrocytes shown in blue. (Credit: UC Berkeley.)

Newly generated neurons in the hippocampus that get activated by the amygdala may provide a “blank slate” on which a new fearful memory can be strongly imprinted, according to UC Berkeley researchers.

The finding has implications for post traumatic stress disorder (PTSD) and other problems caused by faulty regulation of emotional memory.

The team now plans to see whether other negative stimuli, such as stress and anxiety, similarly cooperate with amygdala activity to alter neurogenesis in the hippocampus.

Ref.: Basolateral amygdala regulation of adult hippocampal neurogenesis and fear-related activation of newborn neurons (June 14, 2011 AOP Molecular Psychiatry)

This cross section of a rat brain shows how emotional information from the amygdala promotes the generation of new nerve cells from adult neural stem cells in the hippocampus (left). These neurons can be activated by fear during a critical 2-4 week period after birth, helping to imprint a memory of the fearful situation. Without input from the amygdala (right), the hippocampus produces fewer new neurons. (Credit: UC Berkeley)