Journal of Neuroscience, Vol 2, 562-571, Copyright © 1982 by Society for Neuroscience
Development of the electrophysiological properties of Y-cells in the kitten's medial interlaminar nucleus
JR Wilson, DE Tessin and SM Sherman
Single unit, extracellular recordings were made in the medial interlaminar
nucleus (MIN) of adult cats and of kittens at 2, 4, 6, 8, 12, and 16 weeks
of age. MIN is part of the dorsal lateral geniculate nucleus, and nearly
all of its recorded neurons are Y-cells in adult cats. We find that Y-cells
in the MIN of younger kittens have long latencies to optic chiasm
stimulation, large receptive fields without surrounds, low spatial and
temporal resolutions, and nearly absent spontaneous activity. Responses to
hand-held light stimuli are typically poor and inconsistent. Also, most of
these immature Y-cells exhibit only linear response properties when tested
with a counterphased modulated grating pattern. All of the above
characteristics gradually develop to adult values over several months of
the postnatal period. The percentage of cells with nonlinear response
properties becomes adult-like near 8 weeks of age, while both spatial and
temporal resolutions are still developing at 16 weeks of age. Latencies and
receptive field center sizes achieve adult values at about 12 weeks of age.
The immature properties of these neurons are similar to those recorded from
abnormal cells in the area of the medial interlaminar nucleus innervated by
the deprived eye of monocularly deprived adult cats. This indicates that
the adult deprived Y-cells probably fail to develop and thus retain their
immature properties.