Affiliations: Department of Neurology, Showa University School of
Medicine, Shinagawa-ku, Tokyo, Japan
Note: [] Corresponding author: Hiroo Ichikawa, Department of Neurology,
Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo
142-8666, Japan. Tel.: +81 3 3784 8781; Fax: +81 3 3784 1936; E-mail:
[email protected]
Abstract: The clinical significance and characteristics of writing errors in
bulbar-onset amyotrophic lateral sclerosis (ALS) are not clear. We
retrospectively investigated writing samples in 19 patients with bulbar-onset
ALS without preceding extra-motor symptoms. Co-development of dementia and/or
aphasia was also explored and single photon emission computed tomography
(SPECT) images of the brain were reviewed. As a result, a high prevalence of
writing errors (15 of the 19 patients) was found. Of note were isolated writing
errors with neither dementia nor aphasia verified in 2 patients whose
dysarthria was mild enough to evaluate spoken language. The remaining 13
patients also showed agraphia, but either dysarthria was too severe to evaluate
aphasia or frontotemporal dementia (FTD)-like features co-existed. Of these
patients, one who initially lacked dementia subsequently developed FTD-like
features. The frequent writing errors were omission or substitution of kana
letters and syntactic errors. SPECT images showed bilateral or left-side
dominant hypoperfusion in the frontotemporal lobes as a consistent feature.
These results show that patients with bulbar-onset ALS frequently exhibit
agraphic writing errors and that these are not merely consequences of dementia
or aphasia. However, these writing errors may indicate the involvement of
frontotemporal language-related areas beyond the primary motor cortex.
