Representations in human primary visual cortex drift over time

Primary sensory regions are believed to instantiate stable neural representations, yet a number of recent rodent studies suggest instead that representations drift over time. We analyzed a massive fMRI dataset using an image-computable encoding model and found systematic changes in model fits that exhibited cumulative drift over many months. Convergent analyses pinpoint changes in neural responsivity as the source of the drift, while population-level representational dissimilarities between visual stimuli were unchanged, suggesting that downstream cortical areas may read-out a stable representation, even as representations within V1 drift.