Left ipsilesional neglect for visual imagery: a mental image generation impairment?

Area of Science:

• Neuroscience
• Cognitive Psychology
• Neurology

Background:

• Unilateral brain damage can cause spatial neglect, typically affecting contralesional space.
• Neglect is often categorized into perceptual and representational forms, with distinct underlying mechanisms hypothesized.
• The role of hemispheric specialization in visual imagery and neglect remains an area of active research.

Observation:

• A patient (CN) with unilateral left posterior brain damage presented with a rare form of left ipsilesional neglect.
• This neglect was specifically confined to mental representations, sparing perceptual processing.
• CN's condition challenges traditional models of spatial neglect.

Findings:

• The patient's unique clinical presentation supports the hypothesis of dissociable mechanisms for perceptual and representational neglect.
• Left hemisphere lesions may disrupt visual imagery processes, leading to representational neglect.
• The findings suggest that left brain damage can impair the mental generation of visual representations, potentially affecting either side of the imagined scene.

Implications:

• This case provides critical evidence for distinct neural substrates underlying perception and mental imagery.
• Understanding representational neglect deepens insights into hemispheric contributions to visual representation.
• The findings may inform therapeutic strategies for patients with brain injuries affecting cognitive functions.