Preservation of vision by the pulvinar following early-life primary visual cortex lesions

Conscious vision is believed to depend upon an intact primary visual cortex (V1), although injury in early life is often accompanied by the preservation of visual capacity, unlike in adulthood. The middle temporal area (MT) receives input from the retinorecipient koniocellular layers of the lateral geniculate nucleus (LGN) and the more recently described medial subdivision of the inferior pulvinar (PIm) of the thalamus, pathways that potentially contribute to preservation of vision after early damage to V1.

We examined the potential of these pathways to the long-term preservation of vision after permanent lesions of primate V1 in early and adult life by using a combination of neural tracing and diffusion MRI. We show that early-life V1 lesions lead to less pruning of the retina-pulvinar-MT pathway than is observed in control or adult lesion animals.

These findings suggest that sustained visual input through the pulvinar to MT following a lesion of V1 in early life has the capacity to afford improved visual outcomes.