Affiliations: Department of Neurology, Mitsui Memorial Hospital,
Tokyo, Japan
Note: [] Corresponding author: Yasuhisa Sakurai, MD, PhD., Department of
Neurology, Mitsui Memorial Hospital, 1 Kanda-Izumi-cho, Chiyoda-ku, Tokyo
101-8643, Japan. Tel.: +81 3 3862 9111; Fax: +81 3 5687 9765; E-mail:
ysakurai-tky@umin.ac.jp
Abstract: Objective: To clarify whether agraphia or alexia occurs in lesions
of the left posterior middle temporal gyrus. Methods: We assessed the
reading and writing abilities of two patients with this lesion using kanji
(Japanese morphograms) and kana (Japanese syllabograms). Results: Patient
1 first presented with pure alexia more impaired for kana after an infarction
in the left middle and inferior occipital gyri and right basal occipital
cortex, and after a second infarction in the left posterior middle temporal
gyrus adjoining the first lesion he showed alexia with agraphia for kanji and
worsened alexia for kana; kanji alexia recovered over the following six to 10
months. Patient 2 presented with alexia with agraphia for kanji following a
hemorrhage in the left posterior middle and inferior temporal gyri, which
resolved to agraphia for kanji at two months after onset. Kana nonword reading
was also slightly impaired, but became normal by six months post-onset. In both
patients, kanji agraphia was mostly due to impaired character recall. Conclusion: The present patients demonstrate that damage to the left posterior
middle temporal gyrus alone can cause agraphia for kanji. If the adjacent mid
fusiform/inferior temporal gyri (Area 37) are spared, the kanji alexia is
transient.
Keywords: Pure agraphia, kanji, kana, alexia with agraphia, posterior middle temporal gyrus, fusiform gyrus, visual word form area
