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Virtual Prism Adaptation Therapy: Protocol for Validation in Healthy Adults
Published on: February 12, 2020
Prism adaptation improves visual search in hemispatial neglect
Styrmir Saevarsson1, Arni Kristjánsson, Helmut Hildebrandt
1Department of Psychology, Neuropsychology, University of Freiburg, Freiburg, Germany. saevarsson@daad-alumni.de
Neuropsychologia
|December 23, 2008
Summary
Prism adaptation improved visual search in hemispatial neglect patients, but only when tasks lacked time limits or feedback. These benefits disappeared when feedback was provided.
Area of Science:
- Neuroscience
- Cognitive Psychology
Background:
- Visuomotor prism adaptation can alter spatial attention.
- Hemispatial neglect is a condition affecting spatial attention.
Purpose of the Study:
- To investigate the impact of prism adaptation on visual search and neglect tests in chronic hemispatial neglect patients.
- To determine if feedback and time constraints influence prism adaptation's therapeutic effects.
Main Methods:
- Two experiments were conducted using 10-degree prism adaptation.
- Experiment 1: Time-restricted visual search with feedback.
- Experiment 2: Unlimited time visual search without feedback.
Main Results:
- Prism adaptation showed no accuracy improvement in time-restricted visual search or standard neglect tests.
- Accuracy improved in visual search and neglect tests under unlimited time and no feedback conditions.
- Therapeutic effects lasted 90-120 minutes; response times improved across tasks after adaptation.
Conclusions:
- Prism adaptation enhances visual search and neglect test performance when tasks are not speeded or time-restricted and lack feedback.
- Feedback can negate the beneficial effects of prism adaptation in neglect patients.
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