Behavioral Properties of the Trigeminal Somatosensory System in Rats Performing Whisker-Dependent Tactile Discriminations

摘要: To address several fundamental questions regarding how multiwhisker tactile stimuli are integrated and processed by the trigeminal somatosensory system, a novel behavioral task was developed that required rats to discriminate width of either wide or narrow aperture using only their large mystacial vibrissae. Rats quickly acquired this could accurately between apertures very similar width. Accurate discriminations number intact facial whiskers. Systematic removal individual whiskers caused decrease in performance directly proportional removed, indicating information from multiple is as gauge In different groups rats, sets were removed patterns preferentially left whisker rows arcs intact. These removals decreases performance, within vibrissal array functionally equivalent during task. Lesions barrel cortex abolished ability discriminate, demonstrating region critically involved behavior. Interestingly, sectioning nerve, which movements, did not affect perform accurate discriminations, active movements necessary for Collectively, these results indicate system forms internal representations external (in case, width) integrating input many can function fine-grained distance detector without movements.