The Effect of Amputation on Spatial Visual Representation in Peripersonal Space

The recruitment status of this study is unknown because the information has not been verified recently.
Verified March 2007 by Hadassah Medical Organization.
Recruitment status was  Not yet recruiting
Sponsor:
Information provided by:
Hadassah Medical Organization
ClinicalTrials.gov Identifier:
NCT00458757
First received: April 10, 2007
Last updated: May 12, 2008
Last verified: March 2007

April 10, 2007
May 12, 2008
November 2007
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Complete list of historical versions of study NCT00458757 on ClinicalTrials.gov Archive Site
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The Effect of Amputation on Spatial Visual Representation in Peripersonal Space
The Effect of Upper Arm Amputation and the Use of Prosthetics on Spatial Visual Representation in Peripersonal Space - a Behavioural Study

In this study, we wish to find behavioral evidence for the question whether an amputation of the arm can lead to changes in visual perception or motor responses to objects in peripersonal space. We hypothesize that changes in the motor and somatosensory hand-related cortices following amputation might lead to changes in parietal hand-related areas. The consequence of these parietal changes should be reflected behaviorally in reduced perception/attention/responses to hand-related objects in the space ipsilateral to the amputation. We further hypothesize that the use of prosthetics may provide the necessary visual feedback to maintain an intact hand representation and therefore lead to lesser cortical reorganization in both visual and somatosensory cortical areas.

In a recent fMRI study (Makin TR. et al., J. Neurosci. 2007), we found extended cortical representation for a visual stimulus provided that it is presented close to the hand. It is therefore interesting to ask whether changes in the brain following limb amputation might induce changes in the amputees' perception of the body and consequently it's surrounding. In this study, we wish to find behavioral evidence for the question whether an amputation of the arm can lead to changes in visual perception or motor responses to objects in peripersonal space. We hypothesize that changes in the motor and somatosensory hand-related cortices following amputation might lead to changes in parietal hand-related areas. Consequently, we expect to find reduced perception/attention/responses to hand-related objects in the space ipsilateral to the amputation.

In this experiment we plan to employ a paradigm which is inspired by the affordance effect, originally introduced by Tucker and Elice (1998): we will present subjects with brief images of either manipulable or non manipulable objects in either the left or right visual field. The subjects will be required to determine whether the object contains a metal or not, by moving either their left or their right shoulder. We predict that while the control group of normal subjects would show a congruency effect (that is superior performance (faster and more accurate responses) when the responding shoulder is congruent with the position of the objects, the amputees will show spatial biases towards the non-amputated side. This effect should be more prominent for the manipulable objects.

Observational
Observational Model: Case Control
Time Perspective: Prospective
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Non-Probability Sample

In this experiment we plan to employ a paradigm which is inspired by the affordance effect, originally introduced by Tucker and Elice (1998): we will present subjects with brief images of either manipulable or non manipulable objects in either the left or right visual field. The subjects will be required to determine whether the object contains a metal or not, by moving either their left or their right shoulder. We predict that while the control group of normal subjects would show a congruency effect (that is superior performance (faster and more accurate responses) when the responding shoulder is congruent with the position of the objects, the amputees will show spatial biases towards the non-amputated side. This effect should be more prominent for the manipulable objects.

Upper Limb Amputees
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*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Not yet recruiting
40
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Inclusion Criteria:

  • Upper limb amputee, amputation above wrist.
Both
18 Years and older
Yes
Contact: Isabella Schuartz, MD 00 972 50 8573783 isabellas@hadassah.org.il
Israel
 
NCT00458757
090767-amputy-HMO-CTIL
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Hadassah Medical Organization
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Principal Investigator: Isabella Schuartz, MD Rehabilitation Dep. Hadassah Medical Hospital, Mount Scopus, Jerusalem
Hadassah Medical Organization
March 2007

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP