Tactile perception: Do distinct subpopulations explain differences in mislocalization rates of stimuli across fingertips?

In a previous study we were able to demonstrate that the Cutaneous Rabbit Effect (CRE) could be induced across fingertips using a form of the reduced rabbit paradigm and electrotactile stimuli. The CRE, as used here, is an illusory phenomenon where two stimuli are rapidly at a site and then a stimulus is presented to a nearby site. The perception of the second of the stimuli is not at its presented location but at a site between the first and last stimuli. In this experiment, though the overall population did perceive the mislocalized stimuli as the CRE would predict, some subjects were very infrequently observed to mislocalize stimuli due to the CRE or other effects. Here we further examine this phenomena, attempting to identify whether a subpopulation exists that rarely mislocalizes stimuli on their fingertips. To test for this subpopulation, we reexamined the collected data from the previously published experiment and other unpublished data relating to that study. By examining these data for rates of mislocalization utilizing our previous metric we identified that there is a perceptual subpopulation that very infrequently misidentifies the location of a fingertip stimulus.

► In the population, mislocalization of stimulus location on forearms is frequent.
► In the population, mislocalization of stimulus location on fingertips is frequent.
► Using electrotactile stimuli, fingertip mislocalization is rare in a subpopulation.
► These subjects never mislocalize stimuli onto a fingertip that they attend to.