Differential effects of aging on fore- and hindpaw maps of rat somatosensory cortex.

Getting older is associated with a decline of cognitive and sensorimotor abilities, but it remains elusive whether age-related changes are due to accumulating degenerational processes, rendering them largely irreversible, or whether they reflect plastic, adaptational and presumably compensatory changes. Using aged rats as a model we studied how aging affects neural processing in somatosensory cortex. By multi-unit recordings in the fore- and hindpaw cortical maps we compared the effects of aging on receptive field size and response latencies.

Short-term functional plasticity of cortical and thalamic sensory representations and its implication for information processing.

We studied phenomena, constraints, rules, and implications of cortical plastic reorganization produced by input coactivation patterns in primary somatosensory cortex of adult rats. Intracortical microstimulation (ICMS) and an associative pairing of tactile stimulation (PPTS) induced plastic changes within minutes to hours that were fully reversible. Reorganization of receptive fields and topographic maps was studied with electrophysiologic recordings, mapping techniques, and optical imaging of intrinsic signals.