ABSTRACT
In the nervous system, the response to injury involves not only the neurons that are lesioned, but also the response of the entire system to which they belong. Lesions in one part of a neural system might produce degenerative changes, or compensatory plasticity, in neurons at other locations in the system; such changes may be beneficial or detrimental to the systems overall function. Full characterisation the response to injury requires information on many different levels of analysis; ultimately, the relationship between the type, location and extent of lesions, the cellular processes that underlie plastic or degenerative changes in damaged or disconnected neurons, and the extent and adaptive value of these changes in the connections between neurons need to be understood. While far from complete, considerable progress in characterising the responses of nervous systems to injury has been obtained from studying sensory pathways. The relatively tractable interconnections of the somatosensory system have, for many decades, provided a means of studying plastic reorganisation of neurons in response to injury. More recently, studies of somatosensory lesions have explored the relationship between the resultant functional changes in somatosensory representations and their perceptual consequences.
