A paradigm for determination of direct drug-induced modulatory alterations in Purkinje cell activity during treadmill locomotion

This paper describes a paradigm employing chronic single unit recording techniques and videotape analysis of treadmill locomotion in order to determine drug-induced modulation of sensorimotor neuronal activity. Animals implanted with a chronic headstage microdrive unit and an indwelling jugular cannula are trained to walk on a treadmill (10 s on, 10 s off). Characteristically, cerebellar Purkinje cells recorded 1-1.5 mm from midline, exhibit increased rates of discharge in phase with movement of specific limbs during a particular stage of the step-swing cycle, as assessed by video analysis of locomotor patterns. Drug-induced alterations in this movement-correlated discharge relative to changes in the spontaneous firing rate can then be determined to assess drug-induced neuromodulatory effects beyond general non-specific excitatory or inhibitory actions.