Adolescent stress remodels synapses in the sensory thalamus and impairs tactile discrimination in mice

Adolescent stress can lead to persistent behavioral issues and brain dysfunction, often linked to sensory perception abnormalities. The biological basis for these sensory changes is not well understood. Here, we demonstrate that social isolation during adolescence, but not adulthood, remodels the structure and function of brain circuits that process touch in mice. Specifically, isolation increases the number of afferents to each neuron while weakening individual connections, and these changes depend on the activation of glucocorticoid receptors in thalamic neurons. Mice exposed to adolescent isolation also show reduced ability to distinguish fine tactile differences, suggesting a functional impact of the altered thalamic circuitry. Cohabitation with another mouse can partially reverse the synaptic effects of adolescent isolation. Our findings identify the sensory thalamus as a vulnerable site for adolescent stress and show how social experiences during this period can remodel sensory circuits, providing new directions for preventing or treating stress-related sensory problems.