Threshold level, sinusoidal stimuli are used to elicit phase-locked activity from cutaneous mechanoreceptors selectively, for the purpose of evaluating single-unit activity in multiunit peripheral nerve recordings. Each receptor is characterized by its response to a range of mechanical stimuli and by the size and location of its receptive field. This information is used to determine the number and type of units present in multiunit recordings made with chronically implanted electrodes and to follow the presence of the units in the recordings over time. This approach can be used with any type of composite neural recording in which units can be selectively activated and classified.