[Difficulties in face identification after lesion in the left hemisphere]

Area of Science:

• Neuroscience
• Cognitive Psychology
• Neurolinguistics

Background:

• The study investigates a rare case of acute neurological deficit affecting a patient's ability to name familiar faces.
• The patient presented with symptoms including alexia, hemianopia, achromatopsia, and anomia, following a left hemisphere infarct.

Observation:

• Despite intact visual recognition of objects and places, the patient experienced familiarity with famous faces but could not retrieve associated biographical information.
• Neuropsychological examination confirmed preserved face recognition units and the ability to distinguish familiar from unfamiliar faces.
• The patient could access semantic-biographic information when prompted by names, indicating intact semantic stores.

Findings:

• The deficit was interpreted as a disconnection between face recognition units and person identity nodes within a modular-sequential model of face recognition.
• This condition differs from classic prosopagnosia, where familiarity and categorization of faces are impaired.
• The findings suggest a specific left-hemisphere role in accessing semantic-biographic information for facial recognition, complementing the right hemisphere's structural analysis role.

Implications:

• This case supports the validity of the modular-sequential model of face recognition.
• It underscores the significant, yet often overlooked, contribution of the left hemisphere to facial recognition and personal identity retrieval.
• The findings may inform future research on cognitive deficits and brain lateralization in face processing.