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The effect of the Ebbinghaus illusion on grasping behaviour of children.
Exp Brain Res. 2001 Mar; 137(2):237-45.EB

Abstract

Within the context of the Ebbinghaus illusion, adults regularly misjudge the physical size of a centre disc, yet scale their hand aperture according to its actual size. Separate visual pathways for perception and action are assumed to account for this finding. The dorsal visual stream is said to elaborate on egocentric (visuomotor), while the ventral stream is involved in allocentric transformations (object recognition). This study examines the ontogenetic development of this dissociation between perception and action in 35 children between the ages of 5 and 12 years. We report four major results. First, when children judged object size without grasping the disc, their judgements were deceived by the illusion to the same extent as adults. However, when asked to estimate size and then to grasp the disc, young children's (5-7 years) perceptual judgements became unreliable, while adults were still reliably deceived by the illusion in 80% of their trials. Second, the younger the children, the more their aperture was affected by the illusional surround. Discs of the same size were grasped with a smaller aperture when surrounded by a small annulus, although they were perceived as being larger. Third, young children used the largest safety margin during grasping. Fourth, the reliance on visual feedback decreased with increasing age, which was documented by shorter movement times and earlier maximum hand opening during grasping in the older children (feedforward control). Our results indicate that grasping behaviour in children is subject to an interaction between ventral and dorsal processes. Both pathways seem not to be functionally segregated in early and middle childhood. The data are inconclusive about whether young children predominantly use a specific visual stream for either a perceptual or motor task. However, our data demonstrate that children were relying on both visual processing streams during perceptual as well as visuomotor tasks. We found that children used egocentric cues to make perceptual judgements, while their grasping gestures were not exclusively shaped by viewer-centred but also by object-centred information.

Authors+Show Affiliations

Department of Psychology, University of Düsseldorf, Germany.No affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article

Language

eng

PubMed ID

11315553

Citation

Hanisch, C, et al. "The Effect of the Ebbinghaus Illusion On Grasping Behaviour of Children." Experimental Brain Research, vol. 137, no. 2, 2001, pp. 237-45.
Hanisch C, Konczak J, Dohle C. The effect of the Ebbinghaus illusion on grasping behaviour of children. Exp Brain Res. 2001;137(2):237-45.
Hanisch, C., Konczak, J., & Dohle, C. (2001). The effect of the Ebbinghaus illusion on grasping behaviour of children. Experimental Brain Research, 137(2), 237-45.
Hanisch C, Konczak J, Dohle C. The Effect of the Ebbinghaus Illusion On Grasping Behaviour of Children. Exp Brain Res. 2001;137(2):237-45. PubMed PMID: 11315553.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - The effect of the Ebbinghaus illusion on grasping behaviour of children. AU - Hanisch,C, AU - Konczak,J, AU - Dohle,C, PY - 2001/4/24/pubmed PY - 2001/8/31/medline PY - 2001/4/24/entrez SP - 237 EP - 45 JF - Experimental brain research JO - Exp Brain Res VL - 137 IS - 2 N2 - Within the context of the Ebbinghaus illusion, adults regularly misjudge the physical size of a centre disc, yet scale their hand aperture according to its actual size. Separate visual pathways for perception and action are assumed to account for this finding. The dorsal visual stream is said to elaborate on egocentric (visuomotor), while the ventral stream is involved in allocentric transformations (object recognition). This study examines the ontogenetic development of this dissociation between perception and action in 35 children between the ages of 5 and 12 years. We report four major results. First, when children judged object size without grasping the disc, their judgements were deceived by the illusion to the same extent as adults. However, when asked to estimate size and then to grasp the disc, young children's (5-7 years) perceptual judgements became unreliable, while adults were still reliably deceived by the illusion in 80% of their trials. Second, the younger the children, the more their aperture was affected by the illusional surround. Discs of the same size were grasped with a smaller aperture when surrounded by a small annulus, although they were perceived as being larger. Third, young children used the largest safety margin during grasping. Fourth, the reliance on visual feedback decreased with increasing age, which was documented by shorter movement times and earlier maximum hand opening during grasping in the older children (feedforward control). Our results indicate that grasping behaviour in children is subject to an interaction between ventral and dorsal processes. Both pathways seem not to be functionally segregated in early and middle childhood. The data are inconclusive about whether young children predominantly use a specific visual stream for either a perceptual or motor task. However, our data demonstrate that children were relying on both visual processing streams during perceptual as well as visuomotor tasks. We found that children used egocentric cues to make perceptual judgements, while their grasping gestures were not exclusively shaped by viewer-centred but also by object-centred information. SN - 0014-4819 UR - https://www.unboundmedicine.com/medline/citation/11315553/The_effect_of_the_Ebbinghaus_illusion_on_grasping_behaviour_of_children_ L2 - https://dx.doi.org/10.1007/s002210000655 DB - PRIME DP - Unbound Medicine ER -