Abstract
Electrophysiological and psychophysical data indicate that grasping observation automatically orients attention toward the incoming interactions between the actor’s hand and the object. The aim of the present study was to clarify if this effect facilitates the detection of a graspable object with the observed action as compared to an ungraspable one. We submitted participants to an object-identity probability cueing experiment in which the two possible targets were of the same dimensions but one of them presented sharp tips at one extreme while the other presented flat faces. At the beginning of each trial the most probable target was briefly shown. After a variable interval, at the same position, the same (75%) or a different target (25%) was presented. Participants had to press a key in response to target appearance. Superimposed to the video showing cue and target, an agent performing the reaching and grasping of the target was presented. The kinematics of the action was or was not suitable for grasping the cued target, according to the absence or presence of the sharp tips. Results showed that response was modulated by the probability of target identity but only when the observed kinematics was suitable to grasp the attended target. A further experiment clarified that response modulation was never present when the superimposed video always showed the agent at a rest position. These findings are discussed at the light of neurophysiological and psychophysical literature, considering the relationship between the motor system and the perception of objects and of others’ actions. We conclude that the prediction of the mechanical events that arise from the interactions between the hand and the attended object is at the basis of the capability to select a graspable object in space.
Highlights
Selective attention is the name given to the capability of selecting a particular stimulus according to its physical properties and way of presentation, or to previous contingencies and instructions
Bonferroni post hoc analyses indicated that when the kinematics was congruent with the Cue, reaction time (RT) were faster in same trials (261.83 ± 8.36 ms) than in different trials (266.72 ± 8.67 ms; p = 0.04)
Given the impossibility to design an experiment considering the counterbalance between the two types of kinematics, it is not possible to exclude that the absence of the facilitating effect for the sharp object was determined by the object itself and not by the observation of an incongruent kinematics
Summary
Selective attention is the name given to the capability of selecting a particular stimulus according to its physical properties and way of presentation, or to previous contingencies and instructions. Attention orienting toward graspable objects attention derives from mechanisms that are intrinsic to the circuits underlying perception and action This account is deeply rooted in neurophysiological findings on how space is coded and transformed into action in the nervous system. Space is coded in a series of parietofrontal circuits working in parallel (Rizzolatti et al, 1997; Matelli and Luppino, 2001; Craighero, 2014) The activation of those cortical circuits and subcortical centers, involved in the transformation of spatial information into action, determines both an increase in the motor readiness to respond to a specific space sector and a facilitation of processing stimuli coming from that space sector (Moore and Fallah, 2001). There is evidence that preparation to act on an object produces faster processing of stimuli congruent with that object (Craighero et al, 1999; Bekkering and Neggers, 2002; Fischer and Hoellen, 2004; Hannus et al, 2005; Fagioli et al, 2007; Symes et al, 2008)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
