Non-invasive mapping of brain functions and brain recovery: applying lessons from cognitive neuroscience to neurorehabilitation.
Modern cognitive neuroscience provides a powerful framework in which biological models of recovery and neurorehabilitation can be constructed and tested. The widespread availability, relatively low cost and informativeness of functional magnetic resonance imaging (fMRI) has made it the most popular of the techniques available to help with this task. Here, on the basis of functional imaging studies of stroke, diffuse microvascular disease and multiple sclerosis, we argue that processes of motor control and learning in the healthy brain share common mechanisms with those for adaptive functional reorganisation during spontaneous recovery after brain injury or with neurorehabilitation. Relatively stringent criteria can be met to confirm that adaptive functional reorganisation limits disability even in the adult brain: functional brain changes are related to disease burden, can be found in patients with demonstrable pathology but no clinical deficits and can be defined (in motor cortex) even in the absence of volitional recruitment. Initial studies of neurorehabilitation responses using fMRI and transcranial magnetic stimulation demonstrate that adaptive reorganisation can be manipulated directly with both pharmacological and behavioural interventions. The combination of strategies based on a strong biological rational with monitoring their effects using highly informative functional brain imaging methods heralds a new era of scientifically-founded neurorehabilitation.