ޣݣ Stimulus-response relation for slowly adapting myelinated fiber innervating glabrous skin of monkey hand. Stimuli were step inde- ntations of skin of 600 msec duration, delibered in random order of in- tensity at rate of 12/min. Stimulator tip 2 mm in diameter, machimed to one-third spherical surface. Number of impulses eboked by each stimulus is plotted as function of measured intensity of that stimulus.