Sensory deprivation prevents integration of neocortical grafts with the host brain

The histological and electrophysiological properties of embryonic neocortical grafts transplanted into the barrel field of adult rats were compared between the side receiving normal vibrissae input vs. chronic deprivation of input produced by clipping of the recipients vibrissae. Each animal received ablation of the neocortex and transplantation of neocortical tissue bilaterally. Vibrissae were clipped unilaterally immediately after surgery and were trimmed for up to 4 months. Significant differences were found between volume of the grafts as well as the number of grafts showing contact with the wall of the lesion cavity, indicating that the tissue growth was directly influenced by sensory deprivation. Decrements in functional integration with the host brain measured electrophysiologically were also observed.