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Updated: Aug 7, 2026
06:12
Virtual Prism Adaptation Therapy: Protocol for Validation in Healthy Adults
Published on: February 12, 2020
Prism adaptation changes perceptual awareness for chimeric visual objects but not for chimeric faces in spatial
Margarita Sarri1, Lalit Kalra, Richard Greenwood
1Institute of Cognitive Neuroscience and Department of Psychology, University College London, London, UK. m.sarri@ucl.ac.uk
Neurocase
|June 28, 2006
Summary
Prism therapy improved visual awareness for non-face objects in patients with spatial neglect. However, it did not enhance awareness for chimeric faces, suggesting faces may uniquely resist prism benefits.
Area of Science:
- Neuroscience
- Cognitive Psychology
- Rehabilitation Medicine
Background:
- Spatial neglect, often following right-hemisphere stroke, impairs attention to the contralesional side.
- Prism adaptation is a therapeutic approach aiming to improve spatial neglect symptoms.
- The precise mechanisms by which prism therapy affects visual awareness in neglect are debated.
Observation:
- Previous research yielded conflicting results on whether prism therapy improves perceptual awareness in neglect patients.
- This study investigated prism therapy's effect on visual awareness for chimeric stimuli (faces and non-face objects) in three neglect patients.
- Chimeric stimuli present information on both ipsilesional and contralesional sides, allowing for assessment of awareness.
Findings:
- Prism therapy significantly enhanced visual awareness for the identity of the left side of chimeric non-face objects.
- Conversely, prism therapy showed no significant effect on judging the expressions of chimeric faces.
- This suggests that processing facial expressions might be uniquely unaffected by prism therapy in neglect.
Implications:
- Prism therapy may be effective in improving visual awareness for certain types of stimuli in spatial neglect.
- The distinct lack of benefit for chimeric faces suggests specialized neural processing for facial information.
- Further research is needed to elucidate the neural underpinnings of these differential effects and optimize rehabilitation strategies.
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