STRESS RELATED MODULATION OF THE VISUAL RESPONSES IN MOUSE V1

Stress alters sensory processing, yet the mechanisms by which it affects the primary visual cortex remains unclear. Prior work implicates corticotropin-releasing factor (CRF) in stress-dependent changes in visual temporal processing. Interestingly, monosynaptic rabies tracing experiments have revealed direct hypothalamic inputs to V1. These findings suggest that stress may influence V1 through multiple pathways: 1) a systemic HPA-axis pathway via effector hormone corticosterone, 2) via a CRF pathway, or 3) via the effects of direct hypothalamic projections to V1. Using longitudinal two-photon calcium imaging in layer 2/3 of awake mouse V1, we compared neuronal responses during acute restraint stress or via corticosterone administration, while presenting drifting gratings varying in orientation, contrast, and temporal frequency. We found that acute restraint stress selectively shifted neuronal preference toward lower temporal frequencies, an effect absent following corticosterone elevation. Both conditions showed stable orientation tuning and response magnitude with variability across mice that may reflect underlying heterogeneity or latent subpopulations. Taken together these preliminary findings suggest that distinct stress-associated pathways may differentially affect feature selectivity, temporal tuning and gain modulation.