Sunil P. Gandhi
The juvenile brain has the remarkable capacity to rewire itself when challenged by new experiences. The adult brain, although not immutable, retains considerably less potential to rewire. The goal of my research is to develop methods to reactivate plasticity in targeted regions of the brain. Restoring youthful levels of plasticity has the potential to repair the brain following traumatic injury, stroke, and neurodegenerative disease. Moreover, reactivating plasticity might enhance behavioral therapies for psychiatric disorders such as autism and schizophrenia.
Research in my laboratory aims to understand the mechanisms that activate plasticity in the developing visual cortex. During a critical period in childhood, brief alterations of visual experience elicit a rewiring of the visual cortex. In adulthood, the same changes of experience produce little effect. It has been established that critical period plasticity in the visual cortex depends upon the development of inhibitory synaptic neurotransmission. How inhibition makes cortical circuits plastic remains unclear. Recently, we discovered that the transplantation of embryonic inhibitory neurons activates a second period of plasticity in the visual cortex. Our results indicate that inhibitory neurons are developmentally programmed to activate cortical plasticity.
Our current projects seek a physiological explanation for the remarkable effect of transplanted inhibitory neurons on the host brain. Using two-photon fluorescence methods to record the visual inputs to transplanted inhibitory neurons, genetically targeted optical stimulation of these cells and cell-type specific ablation, we will determine how inhibitory neurons shape information processing in the recipient brain and, in turn, control the impact of new experiences on brain circuitry.