Posts Tagged ‘UT southwestern’

New Brain Cells, Stress, And Learned Behavior

Thursday, April 1st, 2010
Stressed Out Mouse

Stressed Out Mouse

A new study by UT Southwestern scientists (Lagace, Donovan, DeCarolis, Farnbauch, Malhotra, Berton, Nestler, Krishnan and Eisch) sheds some light on the connection between stress and neurogenesis.

Eisch and her colleagues performed two experiments related to stress.

1. They exposed mice to a socially stressful experience — confrontation with a more aggressive mouse (the mouse equivalent of a carjacking), then measured the immediate and long term impact on the generation of new brain cells.

2. They irradiated mice to eliminate neurogenesis before exposing the irradiated mice to the same kind of stressful situation.

The scientists made two important findings:

In the first experiment, the stressful situation reduced neurogenesis temporarily (for a few days), and left the mice more likely to be fearful in similar situations.

In the second experiment the irradiated mice showed less fear when exposed to similar stressful situations.

These findings indicate that neurogenesis is key to forming stress memories. This can be a healthy response, educating us on avoidance. (Common sense.) But in cases of inappropriate or chronic stress response, neurogenesis may be overactive.

http://www.pnas.org/content/107/9/4436.abstract