|
|
||||||||
From the Dipartimento di Psicologia (Drs. Farnè and Làdavas, M.L. Demattè), Università degli Studi di Bologna, and Centro Studi e Ricerche in Neuroscienze Cognitive (Drs. Farnè and Làdavas), Cesena, Italy; and Espace et Action UMR-S 534 (Dr. Farnè), INSERM and Université Claude Bernard, Bron, France.
Address correspondence and reprint requests to Dr. A. Farnè, UMR-S 534 Espace et Action INSERM and Université Claude Bernard 16, av. D. Lépine, 69500 Bron, France; e-mail: farne{at}lyon.inserm.fr
Background: The space closely surrounding the body, near peripersonal space, is represented through multisensory coding, as witnessed by the spatial distribution of visualtactile extinction in brain-damaged patients. Typically, tactile stimuli delivered on the contralesional hand are more severely extinguished by visual stimuli presented near to than far from the ipsilesional hand.
Objective: To investigate whether the near peripersonal space is a unitary multisensory representation of the peribody space or is organized in a modular fashion, separately representing different body parts.
Methods: Cross-modal extinction was used to assess right brain-damaged patients with left tactile extinction by presenting a combination of ipsilesional visual and contralesional tactile stimuli, both between homologous body parts (i.e., the two hands and sides of the face) and between nonhomologous body parts (i.e., right hand + left face and right face + left hand).
Results: Visualtactile extinction observed in the near peripersonal space of homologous body parts was more severe than that obtained between nonhomologous body parts. In contrast, cross-modal extinction observed in the far peripersonal space was overall weak and comparable when stimulating homologous or nonhomologous body sectors. In addition, a clear nearfar modulation of visualtactile extinction was obtained only when stimulating homologous, but not nonhomologous, body parts. These findings were observed irrespective of the severity of unisensory tactile extinction
Conclusions: Near peripersonal space is not unitary but is functionally organized in modules and consists of at least two different spatial representations, one around the hand and another around the face, which might be selectively affected in patients with extinction.
Additional material related to this article can be found on the Neurology Web site. Go to www.neurology.org and scroll down the Table of Contents for the December 13 issue to find the title link for this article.
Supported by the Ministry of Education, University, Research, and Oriented Fundamental Research.
Disclosure: The authors report no conflicts of interest.
Received March 7, 2005. Accepted in final form August 17, 2005.
This article has been cited by other articles:
![]() |
T. R. Makin, N. P. Holmes, C. Brozzoli, Y. Rossetti, and A. Farne Coding of Visual Space during Motor Preparation: Approaching Objects Rapidly Modulate Corticospinal Excitability in Hand-Centered Coordinates J. Neurosci., September 23, 2009; 29(38): 11841 - 11851. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. R. Makin, N. P. Holmes, and E. Zohary Is That Near My Hand? Multisensory Representation of Peripersonal Space in Human Intraparietal Sulcus J. Neurosci., January 24, 2007; 27(4): 731 - 740. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |