Abstract

Plasticity is strong during early post-natal age, when the cortical visual circuits are developing. However, adult vision is also flexible, and continuously adapts with experience, molding cortical circuitry to optimally analyze incoming information. In this talk I will present evidence that plastic changes in primary visual cortex are not limited to the developmental period, as commonly thought, but can extend throughout adult life. I will first discuss psychophysical consequences of brief visual deprivation in both typical adult subjects, and also in amblyopia, which is very difficult to treat in adulthood. I will show how plasticity can be boosted by moderate levels of physical exercise, leading to new therapeutic strategies for amblyopia. I will also discuss possible physiological mechanisms underlying adult plasticity. In particular, 7T spectroscopy and BOLD evidence suggests that this short-term plasticity is accompanied by a decrease of GAB Aergic inhibition and by a decrease of BOLD selectivity for eye of origin and spatial frequency of primary visual cortex. Understanding the residual plastic potential of the adult visual cortex, and how to enhance it, is potentially important as the progress in retinal prosthesis technology opens new possibilities for vision restoration in blind people with retinal pathologies, such as retinitis pigmentosa patients with Argus II Retinal Prosthesis.