This project considers the cellular mechanisms underlying development and experience-dependent plasticity in the visual system of mammals. An in vitro slice preparation is employed and dye-filled electrodes are used to record intracellularly and label immature (visually-naive) neurons and neurons affected by visual deprivation. The focus is the dorsal lateral geniculate nucleus (LGN) which is the thalamic relay between the retina and the visual cortex. The LGN is the most peripheral site along the visual pathway where severe morphological and physiological deficits develop in response to brief periods of visual deprivation during the critical period of development. Its functional organization is well-known and its neurophil simpler than that of more central structures such as the visual cortex, thus making it more amenable for analysis. There are two main goals of Dr. Guido's research. His first goal is to examine the cellular integrative properties of visually-deprived LGN neurons, and then to determine the degree to which any changes in these properties correlate with the reported morphological abnormalities. His second goal is to study the postnatal development of these properties to determine the extent to which their normal expression depends on visual experience during the critical period of development. The specific properties that Dr. Guido will be examining are membrane properties and synaptic events, especially those that rely on the activation of the glutamatergic-N-methyl-D-aspartate receptor. This project is important from the point of view of understanding the origin of visual deficits in humans.***//
