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Related Experiment Video

Updated: Jun 7, 2026

Virtual Reality Tools for Assessing Unilateral Spatial Neglect: A Novel Opportunity for Data Collection

Virtual Reality Tools for Assessing Unilateral Spatial Neglect: A Novel Opportunity for Data Collection

Published on: March 10, 2021

Hemianopia and neglect influence on straight-ahead perception.

A Saj¹, J Honoré, C Richard

¹Department of Neurology, Faculty of Medicine, Geneva University Hospital, University of Geneva, Geneva, Switzerland.

European Neurology

|November 3, 2010

Summary

Spatial neglect and hemianopia cause errors in subjective straight ahead perception. Neglect shifts perception rightward, while hemianopia adds rotational changes, indicating distinct neural processing.

Related Experiment Videos

Last Updated: Jun 7, 2026

Virtual Reality Tools for Assessing Unilateral Spatial Neglect: A Novel Opportunity for Data Collection

Virtual Reality Tools for Assessing Unilateral Spatial Neglect: A Novel Opportunity for Data Collection

Published on: March 10, 2021

Area of Science:

Neuroscience
Perception Psychology
Clinical Neurology

Background:

Spatial neglect and hemianopia are common after right hemisphere stroke.
The subjective straight ahead (SSA) perception is crucial for navigation and action.
Previous research offered conflicting interpretations of SSA deviations in neglect.

Purpose of the Study:

To differentiate the effects of spatial neglect and hemianopia on SSA perception.
To analyze both translational and rotational components of SSA deviation.
To investigate the neural basis of SSA coding in the right posterior hemisphere.

Main Methods:

Patients with right hemisphere stroke (with varying combinations of neglect and hemianopia) and controls performed a subjective straight-ahead judgment task in darkness.
Participants adjusted a bar for translation and rotation to align with their perceived straight ahead.
A novel method analyzed translational and rotational errors in parallel.

Main Results:

Spatial neglect caused a rightward translation error in SSA, which was amplified by hemianopia.
Hemianopia, independent of neglect, influenced SSA rotation, with most hemianopic patients showing anticlockwise rotation.
Translation and rotation errors were dissociated, suggesting distinct neural substrates.

Conclusions:

Both spatial neglect and hemianopia contribute to ipsilesional translation errors in SSA.
Hemianopia in neglect patients introduces a counterclockwise rotational error.
The dissociation of rotation and translation errors suggests differential coding by the right posterior hemisphere.