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Updated: May 9, 2026
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Non-invasive Imaging and Analysis of Cerebral Ischemia in Living Rats Using Positron Emission Tomography with 18F-FDG
Published on: December 28, 2014
Agraphia caused by an infarction in Exner's area
Catharina Keller1, Ingo G Meister1
1Universitätsklinik Köln, Klinik und Poliklinik für Neurologie, Kerpener Strasse 62, Köln 50924, Germany.
Summary
Sigmund Exner
Area of Science:
- Neuroscience
- Neurolinguistics
Background:
- Sigmund Exner proposed the medial frontal gyrus's base as the writing center in 1881.
- Writing impairments have been linked to lesions in this specific brain region.
Observation:
- Two patients with strokes affecting the base of the medial frontal gyrus were studied.
- These patients exhibited significant writing disturbances and aphasia.
Findings:
- The observed writing impairments included omitted words and poorly formed words.
- The patients' symptoms align with the hypothesis of a critical role for the Exner area in the writing network.
- This region is suggested to be vital for phoneme-grapheme conversions.
Implications:
- These cases reinforce the importance of the Exner area in the brain's writing network.
- The findings suggest the Exner area's crucial function in the phoneme-grapheme conversion process.
- Further research into this region could enhance understanding of writing disorders and treatments.
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