Neuroplasticity and its implications on rehabilitation

Abstract

For many years following the discovery that specific areas in the brain are related to specific functions in the body, rigid concepts were formed regarding the central nervous system (CNS) being "hard-wired" or fixed and unchanging. This concept of specificity excluded reorganisation potential in the CNS, and therefore no recovery was expected following a CNS lesion, except that due to the resolution of local factors, such as edema and tissue debris (Kelly, 1985; Bach-Y-Rita, 1989). Reasons for the failure of axonal regeneration in the CNS of higher animals are still much debated. Since the last decade, experimental evidence has shown that the CNS is capable of repair and regeneration to a much higher degree than was previously believed (e.g. Raisman, 1969; Carlen et ai, 1978; Aguayo & David, 1981). Results from these studies showed that following a lesion, the CNS undergoes both structural and functional changes via a reorganisation of its connections, known as plasticity. Bishop (1982d) defined plasticity as the 'morphological and functional changes occurring in the CNS in response to neural lesions'. However, this essay, will debate this definition, in that not all structural changes lead to significantly measurable functional changes.