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Attention modulates motor system activation during action observation: evidence for inhibitory rebound.

Schuch S, Bayliss AP, Klein C, Tipper SP - Exp Brain Res (2010)

Bottom Line: We investigated whether this effect is stronger when the observed action is relevant to the observer's task.Results show mu rhythm attenuation when watching the videos relative to baseline.This enhancement was again stronger when making judgments about the grasp than the colour, suggesting that the stronger activation is followed by a stronger inhibitory rebound.

View Article: PubMed Central - PubMed

Affiliation: School of Psychology, Bangor University, Bangor, UK. schuch@psych.rwth-aachen.de

ABSTRACT
Perceiving another individual's actions activates the human motor system. We investigated whether this effect is stronger when the observed action is relevant to the observer's task. The mu rhythm (oscillatory activity in the 8- to 13-Hz band over sensorimotor cortex) was measured while participants watched videos of grasping movements. In one of two conditions, the participants had to later report how many times they had seen a certain kind of grasp. In the other condition, they viewed the identical videos but had to later report how many times they had seen a certain colour change. The colour change and the grasp always occurred simultaneously. Results show mu rhythm attenuation when watching the videos relative to baseline. This attenuation was stronger when participants later reported the grasp rather than the colour, suggesting that the motor system is more strongly activated when the observed grasping actions were relevant to the observer's task. Moreover, when the graspable object disappeared after the offset of the video, there was subsequent mu rhythm enhancement, reflecting a post-stimulus inhibitory rebound. This enhancement was again stronger when making judgments about the grasp than the colour, suggesting that the stronger activation is followed by a stronger inhibitory rebound.

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Related in: MedlinePlus

Paradigm. Participants watched short videos of grasping movements. In the stimulus-offset condition, the cup disappeared after the grasp. In the stimulus-maintenance condition, the cup remained visible after the grasp. In each trial, the cup was grasped at the handle or at the top (precision or power grip). The X on the cup changed colour at the moment of grasp (blue or green). Both grasp and colour varied randomly from trial to trial. One kind of grasp and one colour were more frequent than the other (80% versus 20%, respectively). Participants only responded at the end of a block of 50 videos. In the report-grasp condition, they had to estimate the percentage of trials with the infrequent grasp. In the report-colour condition, the percentage of trials with the infrequent colour had to be estimated (colour figure online)
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Fig1: Paradigm. Participants watched short videos of grasping movements. In the stimulus-offset condition, the cup disappeared after the grasp. In the stimulus-maintenance condition, the cup remained visible after the grasp. In each trial, the cup was grasped at the handle or at the top (precision or power grip). The X on the cup changed colour at the moment of grasp (blue or green). Both grasp and colour varied randomly from trial to trial. One kind of grasp and one colour were more frequent than the other (80% versus 20%, respectively). Participants only responded at the end of a block of 50 videos. In the report-grasp condition, they had to estimate the percentage of trials with the infrequent grasp. In the report-colour condition, the percentage of trials with the infrequent colour had to be estimated (colour figure online)

Mentions: The current study investigates whether automatic action tendencies evoked by visual stimuli depend on whether the perceived action is relevant to the observer’s current task goal. Participants watched videos of grasping movements with an embedded colour change at the moment of the grasp. Whether they had to make a subsequent judgment about the grasp or about the colour was manipulated. A cup was either being grasped at the handle or at the top (i.e. with a precision grip or a power grip). Simultaneously, a grey X presented on top of the cup changed into either blue or green (see Fig. 1). The participants’ task was to either make a later judgment about the grasping movement or about the colour change in separate blocks of trials. Specifically, they had to estimate, at the end of the block, in what percentage of trials the cup had been grasped at the handle, or the X had changed into green. It is important to note that identical videos were shown in both conditions. Thus, the conditions differed only with respect to the task that had to be performed: whether the grasp or the colour change was relevant for later report. The participants did not perform any actions while watching the videos and only responded at the end of the block, after having watched 50 videos.Fig. 1


Attention modulates motor system activation during action observation: evidence for inhibitory rebound.

Schuch S, Bayliss AP, Klein C, Tipper SP - Exp Brain Res (2010)

Paradigm. Participants watched short videos of grasping movements. In the stimulus-offset condition, the cup disappeared after the grasp. In the stimulus-maintenance condition, the cup remained visible after the grasp. In each trial, the cup was grasped at the handle or at the top (precision or power grip). The X on the cup changed colour at the moment of grasp (blue or green). Both grasp and colour varied randomly from trial to trial. One kind of grasp and one colour were more frequent than the other (80% versus 20%, respectively). Participants only responded at the end of a block of 50 videos. In the report-grasp condition, they had to estimate the percentage of trials with the infrequent grasp. In the report-colour condition, the percentage of trials with the infrequent colour had to be estimated (colour figure online)
© Copyright Policy
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC2914260&req=5

Fig1: Paradigm. Participants watched short videos of grasping movements. In the stimulus-offset condition, the cup disappeared after the grasp. In the stimulus-maintenance condition, the cup remained visible after the grasp. In each trial, the cup was grasped at the handle or at the top (precision or power grip). The X on the cup changed colour at the moment of grasp (blue or green). Both grasp and colour varied randomly from trial to trial. One kind of grasp and one colour were more frequent than the other (80% versus 20%, respectively). Participants only responded at the end of a block of 50 videos. In the report-grasp condition, they had to estimate the percentage of trials with the infrequent grasp. In the report-colour condition, the percentage of trials with the infrequent colour had to be estimated (colour figure online)
Mentions: The current study investigates whether automatic action tendencies evoked by visual stimuli depend on whether the perceived action is relevant to the observer’s current task goal. Participants watched videos of grasping movements with an embedded colour change at the moment of the grasp. Whether they had to make a subsequent judgment about the grasp or about the colour was manipulated. A cup was either being grasped at the handle or at the top (i.e. with a precision grip or a power grip). Simultaneously, a grey X presented on top of the cup changed into either blue or green (see Fig. 1). The participants’ task was to either make a later judgment about the grasping movement or about the colour change in separate blocks of trials. Specifically, they had to estimate, at the end of the block, in what percentage of trials the cup had been grasped at the handle, or the X had changed into green. It is important to note that identical videos were shown in both conditions. Thus, the conditions differed only with respect to the task that had to be performed: whether the grasp or the colour change was relevant for later report. The participants did not perform any actions while watching the videos and only responded at the end of the block, after having watched 50 videos.Fig. 1

Bottom Line: We investigated whether this effect is stronger when the observed action is relevant to the observer's task.Results show mu rhythm attenuation when watching the videos relative to baseline.This enhancement was again stronger when making judgments about the grasp than the colour, suggesting that the stronger activation is followed by a stronger inhibitory rebound.

View Article: PubMed Central - PubMed

Affiliation: School of Psychology, Bangor University, Bangor, UK. schuch@psych.rwth-aachen.de

ABSTRACT
Perceiving another individual's actions activates the human motor system. We investigated whether this effect is stronger when the observed action is relevant to the observer's task. The mu rhythm (oscillatory activity in the 8- to 13-Hz band over sensorimotor cortex) was measured while participants watched videos of grasping movements. In one of two conditions, the participants had to later report how many times they had seen a certain kind of grasp. In the other condition, they viewed the identical videos but had to later report how many times they had seen a certain colour change. The colour change and the grasp always occurred simultaneously. Results show mu rhythm attenuation when watching the videos relative to baseline. This attenuation was stronger when participants later reported the grasp rather than the colour, suggesting that the motor system is more strongly activated when the observed grasping actions were relevant to the observer's task. Moreover, when the graspable object disappeared after the offset of the video, there was subsequent mu rhythm enhancement, reflecting a post-stimulus inhibitory rebound. This enhancement was again stronger when making judgments about the grasp than the colour, suggesting that the stronger activation is followed by a stronger inhibitory rebound.

Show MeSH
Related in: MedlinePlus