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Assessment of Static Graviceptive Perception in the Roll-Plane using the Subjective Visual Vertical Paradigm
Published on: April 28, 2020
Visual context modulates the subjective vertical in neglect: evidence for an increased rod-and-frame-effect
1Department of Psychology, General and Experimental Psychology/Neuro-cognitive Psychology, Ludwig Maximilian University, Leopoldstrasse 13, D-80802 Munich, Germany. Johanna.Funk@psy.lmu.de
Neuroscience
|November 16, 2010
Summary
Patients with spatial hemi-neglect show altered perception of verticality. External cues like frame orientation significantly impact their spatial bias, unlike healthy individuals, indicating impaired orientation constancy.
Area of Science:
- Neuroscience
- Cognitive Psychology
- Clinical Neurology
Background:
- Spatial hemi-neglect is characterized by deviations in subjective vertical perception.
- Internal factors like head orientation modulate verticality perception in neglect patients.
Purpose of the Study:
- To investigate how external contextual changes modulate spatial orientation deficits in neglect.
- To analyze the effect of frame orientation on the subjective visual vertical (SVV) in neglect patients.
Main Methods:
- A rod-and-frame task was employed to assess the subjective visual vertical (SVV).
- Participants included neglect patients, brain-damaged controls without neglect, and healthy individuals.
- The effect of frame orientation on SVV judgments was analyzed across groups.
Main Results:
- Neglect patients exhibited a systematic counterclockwise (CCW) tilt in SVV judgments.
- All groups showed a rod-and-frame effect (RFE), but it was significantly enhanced in neglect patients.
- Frame orientation substantially modulated neglect patients' spatial bias, increasing it with CCW tilts and decreasing or reversing it with CW tilts.
Conclusions:
- Neglect patients display a systematic bias in subjective vertical and impaired spatial orientation constancy.
- Enhanced RFE suggests a pathologically increased influence of contextual cues due to impaired gravitational information processing.
- These findings highlight severe perturbations in subjective space and increased reliance on internal/external cues in neglect.
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