Developmental vision determines the reference frame for the multisensory control of action

*Biological Psychology and Neuropsychology, University of Hamburg, Von-Melle-Park 11, D-20146 Hamburg, Germany; and
^‡Department of Experimental Psychology, University of Oxford, South Parks Road, Oxford OX1 3UD, England

Edited by Riitta Hari, Helsinki University of Technology, Espoo, Finland, and approved January 10, 2007 (received for review August 17, 2006)

Abstract

Both animal and human studies suggest that action goals are defined in external coordinates regardless of their sensory modality. The present study used an auditory-manual task to test whether the default use of such an external reference frame is innately determined or instead acquired during development because of the increasing dominance of vision over manual control. In Experiment I, congenitally blind, late blind, and age-matched sighted adults had to press a left or right response key depending on the bandwidth of pink noise bursts presented from either the left or right loudspeaker. Although the spatial location of the sounds was entirely task-irrelevant, all groups responded more efficiently with uncrossed hands when the sound was presented from the same side as the responding hand (“Simon effect”). This effect reversed with crossed hands only in the congenitally blind: They responded faster with the hand that was located contralateral to the sound source. In Experiment II, the instruction to the participants was changed: They now had to respond with the hand located next to the sound source. In contrast to Experiment I (“Simon-task”), this task required an explicit matching of the sound's location with the position of the responding hand. In Experiment II, the congenitally blind participants showed a significantly larger crossing deficit than both the sighted and late blind adults. This pattern of results implies that developmental vision induces the default use of an external coordinate frame for multisensory action control; this facilitates not only visual but also auditory–manual control.

Footnotes

^†To whom correspondence should be addressed. E-mail: brigitte.roeder{at}uni-hamburg.de
Author contributions: B.R. and A.K. designed research; A.K. performed research; B.R., A.K., and T.S. analyzed data; and B.R., A.K., C.S., and T.S. wrote the paper.
The authors declare no conflict of interest.
This article is a PNAS direct submission.
This article contains supporting information online at www.pnas.org/cgi/content/full/0607158104/DC1.
↵ § We use the term “external reference frame” here to refer to eye-centered and environmentally centered reference frames, which have often not been separated in previous research. We are aware that “visual” and “external” reference frames are not necessarily identical. When we speak of “visual reference frames” we mean coordinate systems that require visual input in order to emerge. In the present study, “anatomical reference frame” refers to the somatotopic representation of touch.
Abbreviations:

RT,

reaction time;

IE,

inverse efficiency.