Monocular deprivation
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Monocular deprivation is an experimental technique used by neuroscientists to study
Background
This physiological change was paralleled by dramatic anatomical changes. The layers representing the deprived eye in the lateral geniculate nucleus of the thalamus are atrophied. In V1, ocular dominance columns representing the open eye are dramatically enlarged, at the expense of cortical surface area representing the sutured eye (Fig. 1 - Effect of monocular deprivation on ocular dominance columns. Light areas represent V1 neurons receiving input from an eye which has been injected with radioactive amino acid. Dark areas represent neurons receiving input from the other, noninjected, eye. Image A represents normal ocular dominance columns; Image B represents ocular dominance columns after monocular deprivation). These results were confirmed in the monkey.
In felines, the critical period (the period during which deprivation could cause permanent deficits) can last up to one year with the peak occurring around 4 weeks. In monkeys, the critical period peak is around 6 months.[3] Depriving an eye, for even a few days, during this period is sufficient to cause major changes in ocular-dominance-column anatomy and physiology. However, the results of monocular deprivation in adult cats are not the same. The ocular dominance columns do not show results of being disturbed even after the adult cat has had one of its eyes shut for over a year.[3]