Mechanisms of plasticity in the visual cortex. The Friedenwald Lecture.

X lasticity in the visual cortex underlies amblyopia, which may result from strabismus, anisometropia, astigmatism, form deprivation from cataract, or other optical defects in the eyes. This is sensory-dependent or experience-dependent plasticity, in which optical or motor changes lead to an abnormal pattern of signals that reach the visual cortex. The abnormal pattern of signals in turn leads to changes in the connections within the cortex. There is a critical period during which the connections in the cortex are particularly susceptible to these changes. 1