title: Tactile perception during action observation.
abstract: It has been suggested that tactile perception becomes less acute during movement to optimize motor control and to prevent an overload of afferent information generated during action. This empirical phenomenon, known as "tactile gating effect," has been associated with mechanisms of sensory feedback prediction. However, less attention has been given to the tactile attenuation effect during the observation of an action. The aim of this study was to investigate whether and how the observation of a goal-directed action influences tactile perception as during overt action. In a first experiment, we recorded vocal reaction times (RTs) of participants to tactile stimulations during the observation of a reach-to-grasp action. The stimulations were delivered on different body parts that could be either congruent or incongruent with the observed effector (the right hand and the right leg, respectively). The tactile stimulation was contrasted with a no body-related stimulation (an auditory beep). We found increased RTs for tactile congruent stimuli compared to both tactile incongruent and auditory stimuli. This effect was reported only during the observation of the reaching phase, whereas RTs were not modulated during the grasping phase. A tactile two-alternative forced-choice (2AFC) discrimination task was then conducted in order to quantify the changes in tactile sensitivity during the observation of the same goal-directed actions. In agreement with the first experiment, the tactile perceived intensity was reduced only during the reaching phase. These results suggest that tactile processing during action observation relies on a process similar to that occurring during action execution.
authors.affiliation: Robotics, Brain and Cognitive Sciences Department, Fondazione Istituto Italiano di Tecnologia, via Morego 30, 16163, Genoa, Italy. roberta.vastano@iit.it.
authors.forename: Roberta
authors.initials: R
authors.lastname: Vastano
authors.affiliation: Robotics, Brain and Cognitive Sciences Department, Fondazione Istituto Italiano di Tecnologia, via Morego 30, 16163, Genoa, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Inuggi
authors.affiliation: Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Claudia D
authors.initials: CD
authors.lastname: Vargas
authors.affiliation: Robotics, Brain and Cognitive Sciences Department, Fondazione Istituto Italiano di Tecnologia, via Morego 30, 16163, Genoa, Italy.|Vita-Salute San Raffaele University, via Olgettina 58, 20132, Milan, Italy.|Unit of Experimental Psychology, Division of Neuroscience, IRCCS San Raffaele Scientific Institute, via Olgettina 60, 20132, Milan, Italy.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Baud-Bovy
authors.affiliation: Robotics, Brain and Cognitive Sciences Department, Fondazione Istituto Italiano di Tecnologia, via Morego 30, 16163, Genoa, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Jacono
authors.affiliation: Robotics, Brain and Cognitive Sciences Department, Fondazione Istituto Italiano di Tecnologia, via Morego 30, 16163, Genoa, Italy. thierry.pozzo@iit.it.|INSERM U1093 Cognition, Action et Plasticité Sensorimotrice, Université de Bourgogne, 21078, Dijon, France. thierry.pozzo@iit.it.
authors.forename: Thierry
authors.initials: T
authors.lastname: Pozzo
mesh_terms: D000328:Adult; D001288:Attention / Q000502:physiology*; D005260:Female; D006225:Hand / Q000502:physiology; D018737:Hand Strength; D006801:Humans; D008297:Male; D009068:Movement / Q000502:physiology; D011597:Psychomotor Performance / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D013028:Space Perception; D014110:Touch / Q000502:physiology; D055698:Touch Perception / Q000502:physiology*; D055815:Young Adult
keywords: Effector-dependency; Forward model; Sensory prediction; Tactile attenuation; Time-dependency