Evolution of brain as clinical symptoms: dystypia instead of agraphia

Abstract

Changes in everyday life in recent years have affected brain localization, for example changes in writing from handwriting to typing on a keyboard. Regarding writing, a new term 'dsytypia' first coined by Otsuki et al. (2002) refers a symptoms of typing impairment which cannot be attributed to aphasia, agraphia, apraxia. The following reports of dystypia have indicated at least two causative lesions; one is frontal lobe involving the foot of the middle frontal gyrus and frontal opereculum, and the other is the parietal lobe. We speculate that dystypia with frontal lobe (frontal dystypia) is caused by the impairment of intermediate process from linguistic information to motor reaction such as typing, and dystypia with parietal lesion (parietal type) by the visuo-spatial impairment. Moreover, a term 'dystextia' which refers to an impairment of texting on a cell phone has appeared. Although dystexia is not well established as a pure neurological symptoms because the reports of dystextia include not only the patients with pure dystexia but also texting impairment due to severe aphasia or apraxia or weakness. However, it would be very important to focus on this symptom in future.