Short term changes of cortical body maps following partial vibrissectomy in adult mice

Vibrissae-to-barrels pathway is often used as a model for investigating CNS plasticity. We examined early changes in the cortical representation of row C of vibrissae in adult mice, following vibrissectomy removing all whiskers except row C. The changes of cortical representation of the spared row of vibrissae were mapped with 2-deoxyglucose autoradiography. We found that one day after lesion of vibrissal follicles the areal extent of cortical representation of row C is smaller than normally, but 7 days post lesion it increases significantly, by 60 to 90%, in all cortical layers. Additionally, seven days post-lesion the intensity of labelling was increased in cortical layer V. The result suggest that plasticity that can be observed with 2-deoxyglucose mapping in the barrel cortex is not due to unmasking of existing connection, but to reorganization of connectivity at many levels.