DISTRIBUTION TO CEREBELLAR ANTERIOR LOBE OF CLIMBING AND MOSSY FIBER INPUTS FROM PLANTAR PALMAR CUTANEOUS AFFERENTS

Systematic examination has been made of the potentials evoked in the ipsilateral anterior lobe by single Group II volleys in different branches of cutaneous nerves to the fore-paw and hind-paw of the cat. Field potentials evoked by the mossy and climbing fiber inputs have been recorded along microelectrode tracks arranged so that there has been a comprehensive study through the whole branching foliated structure. In a previous investigation it was shown that large cutaneous nerves of the forelimb and hindlimb have wide fields of action for both the mossy fiber and climbing fiber inputs. In this present investigation it was found that small cutaneous nerves have more localized distributions within these wide fields. This discriminative distribution is exhibited for Group II volleys in the subdivisions of the nerves providing innervation to the palmar and plantar foot pads. It thus appears from this somatotopic investigation that there are pathways to the cerebellum sufficiently specific to give information about the part of the foot that is being stimulated in natural movements. © 1969 Springer-Verlag.