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Grasping preparation enhances orientation change detection.

Gutteling TP, Kenemans JL, Neggers SF - PLoS ONE (2011)

Bottom Line: By analyzing discrimination response probabilities, we found increased perceptual sensitivity to orientation changes when subjects were instructed to grasp the bar, rather than point to it.Here, no differences in visual sensitivity between grasping and pointing were found.The present results constitute first direct evidence for increased perceptual sensitivity to a visual feature that is relevant for a certain skeletomotor act during the movement preparation phase.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychiatry, Rudolf Magnus Institute of Neuroscience, University Medical Center Utrecht, Utrecht, The Netherlands. T.Gutteling@umcutrecht.nl

ABSTRACT
Preparing a goal directed movement often requires detailed analysis of our environment. When picking up an object, its orientation, size and relative distance are relevant parameters when preparing a successful grasp. It would therefore be beneficial if the motor system is able to influence early perception such that information processing needs for action control are met at the earliest possible stage. However, only a few studies reported (indirect) evidence for action-induced visual perception improvements. We therefore aimed to provide direct evidence for a feature-specific perceptual modulation during the planning phase of a grasping action. Human subjects were instructed to either grasp or point to a bar while simultaneously performing an orientation discrimination task. The bar could slightly change its orientation during grasping preparation. By analyzing discrimination response probabilities, we found increased perceptual sensitivity to orientation changes when subjects were instructed to grasp the bar, rather than point to it. As a control experiment, the same experiment was repeated using bar luminance changes, a feature that is not relevant for either grasping or pointing. Here, no differences in visual sensitivity between grasping and pointing were found. The present results constitute first direct evidence for increased perceptual sensitivity to a visual feature that is relevant for a certain skeletomotor act during the movement preparation phase. We speculate that such action-induced perception improvements are controlled by neuronal feedback mechanisms from cortical motor planning areas to early visual cortex, similar to what was recently established for spatial perception improvements shortly before eye movements.

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Main findings.(A) In the orientation change discrimination experiment (1), performance is increased when a grasping action is prepared. This effect occurs for all magnitudes of change tested. (B) No such consistent change in performance was found when luminance was used instead of orientation as a feature to-be discriminated.
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pone-0017675-g003: Main findings.(A) In the orientation change discrimination experiment (1), performance is increased when a grasping action is prepared. This effect occurs for all magnitudes of change tested. (B) No such consistent change in performance was found when luminance was used instead of orientation as a feature to-be discriminated.

Mentions: We found that sensitivity to orientation changes increased when grasping, rather than pointing, see Figure 3 and Table 1. An analysis of (co)variance (ANCOVA) was conducted with factors ACTION (grasping/pointing), CHANGE_MAGNITUDE (small/medium/large change) and covariate ‘order’ (grasping or pointing first). This yielded a significant main effect of ACTION (F(1,14) = 6.56, p = 0.023, partial η2 = 0.32), indicating that the visual sensitivity significantly differed, depending on the instruction to grasp or point. The mean overall sensitivity for grasping (1.32 SD 0.60; Hit rate 59.9% SD 16.1; false alarm rate 16.4% SD 14.4, bias log β 0.08 SD 0.53) was higher than the sensitivity for pointing (1.07 SD 0.63; Hit rate 57.9% SD 20.1; false alarm rate 22.6% SD 15.4, bias log β 0.15 SD 0.62).


Grasping preparation enhances orientation change detection.

Gutteling TP, Kenemans JL, Neggers SF - PLoS ONE (2011)

Main findings.(A) In the orientation change discrimination experiment (1), performance is increased when a grasping action is prepared. This effect occurs for all magnitudes of change tested. (B) No such consistent change in performance was found when luminance was used instead of orientation as a feature to-be discriminated.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3050920&req=5

pone-0017675-g003: Main findings.(A) In the orientation change discrimination experiment (1), performance is increased when a grasping action is prepared. This effect occurs for all magnitudes of change tested. (B) No such consistent change in performance was found when luminance was used instead of orientation as a feature to-be discriminated.
Mentions: We found that sensitivity to orientation changes increased when grasping, rather than pointing, see Figure 3 and Table 1. An analysis of (co)variance (ANCOVA) was conducted with factors ACTION (grasping/pointing), CHANGE_MAGNITUDE (small/medium/large change) and covariate ‘order’ (grasping or pointing first). This yielded a significant main effect of ACTION (F(1,14) = 6.56, p = 0.023, partial η2 = 0.32), indicating that the visual sensitivity significantly differed, depending on the instruction to grasp or point. The mean overall sensitivity for grasping (1.32 SD 0.60; Hit rate 59.9% SD 16.1; false alarm rate 16.4% SD 14.4, bias log β 0.08 SD 0.53) was higher than the sensitivity for pointing (1.07 SD 0.63; Hit rate 57.9% SD 20.1; false alarm rate 22.6% SD 15.4, bias log β 0.15 SD 0.62).

Bottom Line: By analyzing discrimination response probabilities, we found increased perceptual sensitivity to orientation changes when subjects were instructed to grasp the bar, rather than point to it.Here, no differences in visual sensitivity between grasping and pointing were found.The present results constitute first direct evidence for increased perceptual sensitivity to a visual feature that is relevant for a certain skeletomotor act during the movement preparation phase.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychiatry, Rudolf Magnus Institute of Neuroscience, University Medical Center Utrecht, Utrecht, The Netherlands. T.Gutteling@umcutrecht.nl

ABSTRACT
Preparing a goal directed movement often requires detailed analysis of our environment. When picking up an object, its orientation, size and relative distance are relevant parameters when preparing a successful grasp. It would therefore be beneficial if the motor system is able to influence early perception such that information processing needs for action control are met at the earliest possible stage. However, only a few studies reported (indirect) evidence for action-induced visual perception improvements. We therefore aimed to provide direct evidence for a feature-specific perceptual modulation during the planning phase of a grasping action. Human subjects were instructed to either grasp or point to a bar while simultaneously performing an orientation discrimination task. The bar could slightly change its orientation during grasping preparation. By analyzing discrimination response probabilities, we found increased perceptual sensitivity to orientation changes when subjects were instructed to grasp the bar, rather than point to it. As a control experiment, the same experiment was repeated using bar luminance changes, a feature that is not relevant for either grasping or pointing. Here, no differences in visual sensitivity between grasping and pointing were found. The present results constitute first direct evidence for increased perceptual sensitivity to a visual feature that is relevant for a certain skeletomotor act during the movement preparation phase. We speculate that such action-induced perception improvements are controlled by neuronal feedback mechanisms from cortical motor planning areas to early visual cortex, similar to what was recently established for spatial perception improvements shortly before eye movements.

Show MeSH