Mice raised under EE are resistant to stress-induced spine loss and texture discrimination defects. (a) Schematic of EE. (b) EE prevented RS-induced decrease in PV+ IN activity. (c) Both stressed and unstressed EE mice had elevated activation of NG+ neurons compared to unstressed, non-EE control mice. (d) Stress increased SOM+ neuron activation in both control and EE mice; EE had no effect on SOM+ neuron activation. (e,f) EE increased both spine formation (e) and elimination (f) compared to unstressed, non-EE control mice. Stress did not further alter spine dynamics in EE mice. (g) Both stressed and unstressed EE mice exhibited normal texture discrimination.