Bidirectional modifications of visual acuity induced by monocular deprivation in juvenile and adult rats.
Recent electrophysiological studies of rodent visual cortex suggest that, in addition to deprived-eye depression, monocular deprivation (MD) also shifts ocular dominance by potentiation of open-eye responses. We used computer-based, two-choice discrimination tasks to assess the behavioral significance of these findings in rats. As expected, prolonged MD, from postnatal day 21 until adulthood (>150 d) markedly decreased visual acuity through the deprived eye. However, we also found that the acuity through the nondeprived eye was significantly enhanced compared with normally reared controls. Interestingly, when the deprived eye was opened in adults, there was a gradual but incomplete recovery of acuity in the deprived eye preceded by a loss of the enhanced acuity in the nondeprived eye. These changes were reversed by again reclosing the eye. These findings suggest that the bidirectional changes in visually evoked responses after MD are behaviorally meaningful and that significant plasticity is exhibited well into adulthood.
Iny
Karen
K
Howard Hughes Medical Institute, The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Heynen
Arnold J
AJ
Sklar
Erik
E
Bear
Mark F
MF
D000367:Age Factors; D000818:Animals; D001522:Behavior, Animal; D023882:Dominance, Ocular; D005123:Eye / Q000254:growth & development; D008297:Male; D009473:Neuronal Plasticity; D051381:Rats; D020318:Rats, Long-Evans; D012683:Sensory Deprivation; D015348:Vision, Binocular; D015349:Vision, Monocular; D014792:Visual Acuity