Grasping of Real-World Objects Is Not Biased by Ensemble Perception

Frontiers in Psychology

article

Annabel Wing-Yan Fan¹  Lin Lawrence Guo¹  Adam Frost¹  Robert L. Whitwell²  Matthias Niemeier¹  Jonathan S. Cant¹ 

[1] Department of Psychology, University of Toronto Scarborough;The Department of Psychology, The University of British Columbia

关键词: ensemble perception;    grasping;    perception;    electromyography;    support vector machine classification;    two visual stream hypothesis;    action perception dissociation;   

DOI  :  10.3389/fpsyg.2021.597691

学科分类：社会科学、人文和艺术（综合）

来源: Frontiers

【 摘 要 】

The visual system is known to extract summary representations of visually similar objects which bias the perception of individual objects toward the ensemble average. Although vision plays a large role in guiding action, less is known about whether ensemble representation is informative for action. Motor behavior is tuned to the veridical dimensions of objects and generally considered resistant to perceptual biases. However, when the relevant grasp dimension is not available or is unconstrained, ensemble perception may be informative to behavior by providing gist information about surrounding objects. In the present study, we examined if summary representations of a surrounding ensemble display influenced grip aperture and orientation when participants reached-to-grasp a central circular target which had an explicit size but importantly no explicit orientation that the visuomotor system could selectively attend to. Maximum grip aperture and grip orientation were not biased by ensemble statistics during grasping, although participants were able to perceive and provide manual estimations of the average size and orientation of the ensemble display. Support vector machine classification of ensemble statistics achieved above-chance classification accuracy when trained on kinematic and electromyography data of the perceptual but not grasping conditions, supporting our univariate findings. These results suggest that even along unconstrained grasping dimensions, visually-guided behaviors toward real-world objects are not biased by ensemble processing.

【 授权许可】

CC BY