Author:

Abstract

Aim: To review recent advances in our knowledge about the primary visual cortex and animal models of amblyopia and discuss their relevance for current treatment strategies and speculate about alternative future methods.

Methods: A literature-based review was carried out to highlight recent progress and future challenges in research in binocular vision and amblyopia.

Results: Amblyopia is the most common develop­mental disorder of vision, resulting from abnormal visual experience during a critical period early in life. It Is associated with physiological and anatomical changes (plasticity) in the primary visual cortex, which are deemed largely irreversible in adulthood. The classical animal model of amblyopia is mono­cular deprivation (MD) by eyelid suture, but induced or naturally occurring strabismus has also been studied extensively. In recent years, research has concentrated on understanding the neural mechan­isms of binocular integration and of cortical plasticity during the critical period, as well as on exploring new avenues for extending plasticity into adulthood. Three lines of animal research arc presented. First, the optimisation of eye-patching regimens to achieve the best possible visual acuity in both eyes; second, the neurophysiology of strabismic suppression; and third, new strategics for treating amblyopia in adolescents and adults, by means of cither visual training paradigms or drug therapies aimed at restoring cortical plasticity after Ihc end of the critical period.

Keywords: Amblyopia, Animal models, Critical period, Form deprivation, Functional brain imaging, Primary visual cortex, Strabismus, Visual acuity