simultagnosia
Pronunciation: sim-ul-tag-NO-zee-ah
Inability to perceive multiple objects simultaneously, seeing only one object at a time despite normal vision.
Full Definition
Simultagnosia is a visual processing disorder characterized by the inability to perceive more than one object at a time, despite having intact basic visual function. Patients can see individual objects clearly but cannot integrate multiple visual elements into a coherent whole scene. This condition is a key component of Balint's syndrome and typically results from bilateral parietal-occipital lesions. There are two types: dorsal simultagnosia, where patients see only one object in their entire visual field, and ventral simultagnosia, where patients can see multiple objects but cannot group them meaningfully. The condition significantly impairs reading, navigation, and complex visual tasks.
Usage
Usage note: Often part of Balint's syndrome; test with complex visual scenes to distinguish from other visual deficits.
In Context
- "Simultagnosia prevented the patient from reading sentences, able to see only individual letters." — Visual processing assessment
- "The cookie theft picture revealed severe simultagnosia, with attention to isolated details only." — Neuropsychological testing report