Sensation of a "Noisy" Whisker Vibration in Rats

To provide a biological framework to be later applied in robotics, we have devised a delayed comparison task in which subjects discriminate between pairs of vibration delivered either to their whiskers, in rats, or fingertips, in human, with a delay inserted between the two stimuli. The task is to compare two successive stimuli, with different position standard deviations defined by σ1 and σ2. By varying the stimulus duration we have observed that rats’ performance improves for longer stimuli, suggesting that for stimuli with a probabilistic structure, evidence can be accumulated over time. On the other hand a change in stimulus duration biased human subjects. This experiment constrains models for the integration of tactile information in robotics.