To investigate synaptic alteration in the somatosensory cortex related to peripheral sensory blocking, the present study examined synapse number and structure within a single barrel following plucking of the C3 whisker of rat pups. The results indicate that whisker plucking produces no changes in synapse number and size, but does induce an early appearance of perforated synapses at P30 and P60, within the plucked whisker corresponding barrel. Thus, earlier occurrence of perforated synapses may indicate a representation of sensory experience.