What you feel within a move: The spread of tactile attention during goal-directed movements

Georgiana Juravle, Heiner Deubel, Charles Spence
Poster
Time: 2009-07-01  09:00 AM – 10:30 AM
Last modified: 2009-06-04

Abstract


A considerable body of research (Deubel & Schneider, 1996; Eimer et al., 2005) on motor preparation has shown that shortly before the initiation of a movement, attention is directed at the goal location of the movement. These studies argue in favour of attentional facilitation. On the other hand, research on motor control (Bays et al., 2005; Voss et al., 2006) has provided evidence for tactile attenuation/inhibition shortly before contact with the object is made.

In the present study, we investigated the temporal window of tactile attention changes starting with motor preparation, through motor execution up to the moment of contact with the goal object, as well as the post-contact period. Considering the research that has been published on motor preparation and motor control, we expected that tactile discrimination performance would be facilitated in the motor preparation period and to gradually decline during the motor execution period preceding the contact with the object. Tactile discrimination performance was expected to be facilitated once the object had been grasped.

In order to examine the temporal distribution of tactile attention, we used a dual-task paradigm involving a speeded movement task together with a non-speeded tactile discrimination task. A tactor was attached to the palmar region of the right hand of our right-handed participants, between the thumb and the index finger. Following an auditory signal, they grasped a computer mouse and pressed the left mouse button using their index finger. A second beep instructed participants to reach and grasp for a second mouse placed 25 cm in front of the first one, as well as to press the left mouse button. They were instructed to keep hold of the second mouse until they heard a third beep. Once this last beep was presented, the participants returned to the starting position and gave a response regarding the intensity of a single tactile pulse presented during the trial (participants’ discrimination performance -weak vs. strong pulse- was adjusted during a practice session to give 80% correct performance with the hand at rest). The tactile pulse was delivered at various time intervals before, during, and after the movement execution.

These results highlight the differential deployment of tactile attention during the course of the prepared movement. We discuss these findings in the light of the different theories of attentional facilitation and attenuation in goal directed movements.

References
Bays PM, Wolpert DM, Flanagan JR (2001) Perception of the consequences of self-action is temporally tuned and event-driven. Curr Biol 15:1125-1128
Deubel H, Schneider WX (1996) Saccade target selection and object recognition: evidence for a common attentional mechanism. Vision Res 36:1827-1837
Eimer M, Foster B, van Velzen J, Prabhu G (2005) Covert manual response preparation triggers attentional shifts: ERP evidence for the premotor theory of attention. Neurophychologia 43:957-966
Voss M, Ingram JN, Haggard P, Wolpert DM (2006) Sensorimotor attenuation by central motor command signals in the absence of movement. Nat Neurosci 9:26-27

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