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Updated: Jul 6, 2026
07:12
A Gaze-Contingent Display Framework for Perceptual Learning Research with Simulated Central Vision Loss
Published on: April 11, 2025
Selective deficit of mental visual imagery with intact primary visual cortex and visual perception
Valentina Moro1, Giovanni Berlucchi, Jason Lerch
1Department of Psychology and Culture Anthropology, University of Verona, Italy. valentina.moro@univr.it
Summary
Visual mental imagery deficits can occur independently of visual perception, even with an intact primary visual cortex. Findings suggest the left temporal lobe is crucial for visual imagery.
Area of Science:
- Neuroscience
- Cognitive Psychology
Background:
- Debate exists on shared neuronal networks between visual perception and imagery.
- Investigating the role of the primary visual cortex and brain lateralization in visual imagery is ongoing.
Observation:
- Two patients with closed head injury underwent comprehensive testing of mental imagery across multiple sensory and motor domains.
- Lesion mapping revealed significant left temporal lobe involvement in both patients and bilateral parietal lesions in one.
- Primary visual cortex (calcarine cortex) remained intact in both patients.
Findings:
- One patient exhibited isolated visual mental imagery deficits, while the other showed combined visual and tactile imagery deficits.
- Crucially, perceptual, language, and memory functions were unaffected.
- Results indicate visual imagery deficits can be dissociated from visual perception and do not require primary visual cortex integrity.
Implications:
- The left temporal lobe appears to play a significant role in visual mental imagery.
- This research contributes to understanding the neural underpinnings of mental imagery and its potential dissociation from perception.
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