Experience-dependent synaptic changes in the visual cortex in health and disease

This study examines how visual experience impacts neural connectivity and synchrony in typical mice versus those with Fragile X syndrome (FX), a common form of inherited autism characterized by sensory sensitivity, learning challenges, and intellectual disability. Visual stimuli typically evoke synchronized theta oscillations in two brain regions V1 and LM, that help integrate sensory information. In mice with FX, however, these oscillations are weakened, reflecting impaired connectivity and plasticity between V1 and LM. Using advanced imaging and recordings, the study finds that while visual experience strengthens functional connections and dendritic spine structure in typical mice, FX mice show abnormal spine density and length but do not respond adaptively to experience. These findings offer new insights into how visual experience shapes brain connectivity in both typical and FX conditions.