Adolescent social defeat decreases spatial working memory performance in adulthood

Area of Science:

• Neuroscience
• Psychology
• Behavioral Science

Background:

• Adolescent social stress is linked to adult mental illness with cognitive deficits.
• Social stress may disrupt the developing mesocortical dopamine system, crucial for cognitive functions.
• Adolescent social defeat in rats leads to adult dopaminergic hypofunction in the medial prefrontal cortex.

Purpose of the Study:

• To investigate the direct link between adolescent social stress and long-term spatial working memory deficits.
• To assess the impact of adolescent social defeat on cognitive performance in adult rats.

Main Methods:

• Adult rats subjected to adolescent social defeat were trained on spatial working memory tasks (delayed win-shift and T-Maze).
• Cognitive performance was evaluated under various delay periods.
• Reward motivation was assessed using consumption and conditioned place preference tests.

Main Results:

• Adolescent social defeat resulted in delay-dependent spatial working memory deficits in adult rats.
• Memory impairments were observed at 90s and 5min delay periods on the T-maze and win-shift tasks, respectively.
• Deficits were independent of changes in motivation for the food reward.

Conclusions:

• Severe adolescent social stress can cause lasting deficits in cognitive function, specifically spatial working memory.
• Prefrontal dopamine is critical for spatial working memory, suggesting a target for therapeutic intervention.
• Reversing adolescent stress-induced dopaminergic deficiencies may offer a treatment for associated cognitive impairments.