[Loss of mental images]

Area of Science:

• Neuroscience
• Cognitive Psychology
• Neurology

Background:

• Intraventricular meningiomas can affect cognitive functions.
• Loss of mental imagery (aphantasia) is a rare neurological symptom.
• Understanding the neural basis of mental imagery is crucial for cognitive neuroscience.

Observation:

• A 35-year-old male patient developed loss of mental imagery post-surgery for a left trigonum collaterale intraventricular meningioma.
• The patient's symptomatology and its progression were documented.
• The case highlights potential pathophysiological mechanisms including memory disturbance, functional disconnection, and visual agnosia.

Findings:

• The patient's condition closely resembles visual agnosia, potentially due to a partial dissolution of visual memories.
• A literature review of 35 cases indicates incomplete investigation of this disturbance.
• All reviewed cases with unilateral posterior lesions of the dominant hemisphere exhibited visual agnosia or a related form.

Implications:

• This case contributes to understanding the neural correlates of mental imagery.
• Findings suggest visual agnosia may be a key mechanism in acquired aphantasia.
• Further research is needed to fully elucidate the pathophysiology of lost mental imagery and its connection to visual processing deficits.