ABSTRACT
This chapter examines how the timing and patterning of impulse activity might lead to segregation of geniculocortical afferents. It considers an alternative hypothesis for the formation of segregated inputs, one that invokes the existence of eye-specific molecular labels within the cortex, is at odds with most experimental observations. Studies of the development of connections between retinal ganglion cells and their target neurons in the lateral geniculate nucleus (LGN) suggest that structured activity may even play a role long before vision is possible. The results of the experiments permit an important generalization concerning the universality of activity-dependent synaptic interactions. During normal development, such interactions may be driven not only by the normal pattern of use but even earlier before vision begins by patterned spontaneously generated activity. This suggestion raises the possiblility that spontaneously generated activity elsewhere in the central nervous system (CNS) during development may play a similar role in establishing orderly sets of connections.
