Gerstmann's Syndrome and Limb Apraxia: A Single Case Study.

Area of Science:

• Neuroscience
• Neurology
• Clinical Neuropsychology

Background:

• Gerstmann's syndrome (GS) is a debated neurological condition with unclear symptom evolution and neural underpinnings.
• Understanding GS requires detailed neuropsychological assessments and advanced lesion analysis.

Purpose of the Study:

• To investigate the clinical evolution and neuroanatomical correlates of Gerstmann's syndrome.
• To better understand the neural basis of GS symptoms and associated limb apraxia.

Main Methods:

• A single case study of a patient with GS and limb apraxia following a left hemisphere lesion.
• Repeated neuropsychological assessments over four months and video documentation.
• 3D reconstruction and disconnection mapping for grey and white matter lesion analysis.

Main Results:

• The patient consistently exhibited the tetrad of GS symptoms and persistent limb apraxia.
• Neuroanatomical analysis revealed cortical damage in the left inferior and superior parietal cortex, extending to the precuneus.
• Disconnections were identified in fronto-parietal networks and the corpus callosum.

Conclusions:

• This case supports a core neural network for GS involving the left superior parietal lobe, intraparietal cortices, and associated white matter tracts.
• The involvement of the superior longitudinal fasciculus explains the co-occurrence of limb apraxia in GS.