Activity-dependent maintenance and growth of dendrites in adult cortex

AUTOR(ES)

Tailby, Chris

FONTE

National Academy of Sciences

RESUMO

Whereas it is widely accepted that the adult cortex is capable of a remarkable degree of functional plasticity, demonstrations of accompanying structural changes have been limited. We examined the basal dendritic field morphology of dye-filled neurons in layers III and IV of the mature barrel cortex after vibrissal-deafferentation in adult rats. Eight weeks later, the tendency for these neurons to orient their dendritic arbors toward the center of their home barrel was found to be disrupted by the resultant reduced activity of thalamocortical innervation. Measures of spine density and total dendritic length were normal, indicating that the loss of dendritic bias was accompanied by growth of dendrites directed away from the barrel center. This finding suggests that in the mature cortex, the apparently static structural attributes of the normal adult cortex depend on maintenance of patterns of afferent activity; with the corollary that changes in these patterns can induce structural plasticity.

Documentos Relacionados

• Activity-Dependent Activation of TrkB Neurotrophin Receptors in the Adult CNS
• Activity-dependent current distributions in model neurons.
• Context sensitivity of activity-dependent increases in cerebral blood flow
• Activity-dependent accumulation of calcium in Purkinje cell dendritic spines.
• Activity-dependent NMDA receptor degradation mediated by retrotranslocation and ubiquitination