Functional recovery following brain damage: conceptual frameworks and biological mechanisms

Mammals are well known to manifest recovery over time of many functional impairments induced by brain lesions. A brief reveiw is provided of the different conceptual frameworks within which functional recovery has been examined in the literature, and of different neurobiological mechanisms that have been proposed to account for the phenomenon. We observe that these two levels of analysis have frequently been only loosely related. Finally, a newly identified biological mechanism—compensatory collateral sprouting—is described which appears to be closely related to functional recovery in animals with hippocampal lesions, and this is proposed as a powerful new model within which to investigate further the relationship between the phenomenon of functional recovery and its underlying mechanisms.