General Stress Produces Specific Changes in Brain Connections

To determine how the brain changes to sustain pathological arousal after stress, Chinese investigators used a mouse model of anxiety and a novel technology that permits elucidation of specific projections between various limbic structures.

Chronic restraint, an established stressor in animal studies, produced generalized dendritic hypertrophy in the basolateral amygdala, with more maturation of dendrites that project only to the ventral hippocampus (and not to the dorsomedial prefrontal cortex); hypertrophy was associated with increased activity in glutaminergic synapses that strengthened connections between the basolateral amygdala and the ventral hippocampus. The increase in the strength of these connections was correlated with the severit…