It is known that the primary role in formation of the rat vibrissal sensory system in ontogenesis is played by peripheral afferentation, whose lesion at early age leads to an anomal development and, as a consequence, to morphological and physiological changes in the somatosensory cortex. The goal of this work was to study physiological changes of evoked potentials and individual neuron responses in the white rat frontal cortex as well as to study latencies and thresholds of the vibrissal motor evoked potential after a microstimulation of the vibrissal motor representation and a unilateral lesion of contralateral infraorbital nerve on the first postnatal day. It has been shown that this unilateral sensory deprivation leads to an increase of the latency of evoked potentials and of individual neuron responses both in the ipsi- and in the contralateral vibrissal motor representations after the vibrissal pad stimulation on the lesion side. Also observed was a threshold increase and a decrease of the proportion of the short-latent (not longer than 20 ms) motor responses after the contralateral intracortical microstimulation of the studied field. It is the sensory information deficit from the maxillary vibrissae in early ontogenesis which is suggested to cause the observed long-term changes in functional characteristics of the vibrissal motor cortex sensory inputs and motor outputs.