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Objective To determine the features of alexia or agraphia with a left angular or supramarginal gyrus lesion. Methods We assessed the reading and writing abilities of three patients using kanji (Japanese morphograms) and kana (Japanese syllabograms). Results Patient 1 showed kana alexia and kanji agraphia following a hemorrhage in the left angular gyrus and the adjacent lateral occipital gyri. Patient 2 presented with minimal pure agraphia for both kanji and kana after an infarction in the left angular gyrus involving part of the supramarginal gyrus. Patient 3 also showed moderate pure agraphia for both kanji and kana after an infarction in the left supramarginal and postcentral gyri. All three patients made transposition errors (changing of sequential order of kana characters) in reading. Patient 1 showed letter-by-letter reading and a word-length effect and made substitution errors (changing hiragana [one form of kana] characters in a word to katakana [another form of kana] characters and vice versa) in writing. Conclusion Alexia occurs as “angular” alexia only when the lesion involves the adjacent lateral occipital gyri. Transposition errors suggest disrupted sequential phonological processing from the angular and lateral occipital gyri to the supramarginal gyrus. Substitution errors suggest impaired allographic conversion between hiragana and katakana attributable to a dysfunction in the angular/lateral occipital gyri.

A patient with progressive anomia and alexia with agraphia for kanji (Japanese morphograms) is described. The patient showed a deficit in single-word comprehension and on-reading (a type of reading that conveys phonetic value) dominance in kanji reading, i.e. on-preceding (pronouncing first with on-reading, irrespective of its preferred reading) and kun-deletion (inability to recall and recognize kun-reading [another type of reading that conveys meaning]) when reading a single-character kanji. These features were due to loss of lexico-semantic information and thus the patient was regarded as having progressive Gogi (word-meaning) aphasia by Imura, a Japanese manifestation of semantic dementia. Macroscopically, neuropathological examination disclosed atrophy of the left frontotemporal lobe with accentuation in the anterior portion of the temporal lobe. Histologically, there was neuronal loss in the cerebral cortex, hippocampus, parahippocampal gyrus, amygdala, caudate nucleus, and putamen. Ubiquitin-immunoreactive neuronal inclusions were present in the hippocampal dentate granular cells. This case demonstrates that progressive Gogi aphasia is semiologically identical to semantic dementia, and our patient clinicopathologically resembled those of Rossor et al. [Rossor, M.N., Revesz, T., Lantos, P.L., Warrington, E.K. Semantic dementia with ubiquitin-positive tau-negative inclusion bodies. Brain 2000; 123: 267-76.] and Hodges et al. [Hodges, J.R., Davies, R.R., Xuereb, J.H., Casey, B., Broe, M., Bak, T.H., et al. Clinicopathological correlates in frontotemporal dementia. Ann Neurol 2004; 56: 399-406.].

We evaluated the alexia and agraphia of three patients with different lesions using Japanese kanji (morphograms) and kana (phonograms) and made a lesion-to-symptom analysis. Patient 1 (pure alexia for both kanji and kana and minor agraphia for kanji after a fusiform lesion) made more paragraphic errors for kanji, whereas patient 2 (alexia with agraphia for kanji after a posterior inferior temporal lesion) showed severe reading and writing disturbances and more agraphic errors for kanji. Brodmann Area 37 was affected in both patients, but in patient 2 the lesion was located lateral to that in patient 1. Patient 3 showed agraphia without alexia after restricted lesion to the angular gyrus. We believe that pure alexia (patient 1) results from a disconnection between the medial fusiform gyrus and posterior inferior temporal area (the lateral fusiform and inferior temporal gyri), whereas alexia with agraphia for kanji (patient 2), corresponding to lexical agraphia in Western countries, results from damage to the posterior inferior temporal area, in which whole-word images of words are thought to be stored. Furthermore, restricted lesion in the angular gyrus (patient 3) does not produce alexia; the alexic symptom of “angular” alexia with agraphia may be the result of damage to the adjacent lateral occipital gyri.

We describe a patient with progressive aphemia with agrammatism that was later overlaid with buccofacial apraxia and pseudobulbar palsy. Pathological findings were consistent with those of classic Pick's disease with argyrophilic inclusions and neuronal achromasia, except for restricted cortical atrophy in the frontal operculum posterior to the pars opercularis (Brodmann Area 44). In addition, major neuronal loss was confined to the premotor cortex and the anterior half of the precentral gyrus (Area 6), which apparently explained the aphemia. The present case demonstrated that classic Pick's disease can show quite limited cortical atrophy in a patient who clinically presents with progressive aphemia. Also, our patient differed from the progressive non-fluent aphasia patients reported as having Pick's disease, who were all Pick variants, revealing that classic Pick's disease can be included in the spectrum of progressive aphasia syndrome.

To evaluate the role of the sub-cortical white matter and cortical areas of the supramarginal gyrus in short-term memory impairment (shortened digit or letter span) and repetition difficulty, four patients with conduction aphasia and impaired short-term memory and two patients with only short-term memory impairment were given digit span, letter span, speech audiometry and dichotic listening tests. The results showed that in most of the patients letter span was inferior to digit span and that bilateral ear suppression in the dichotic listening test was observed in two patients with a lesion in the inferior part of the supramarginal gyrus, suggesting that what was affected was phonological information and that the supramarginal gyrus was the storage site. The overlapped lesion of conduction aphasia patients with short-term memory impairment was the periventricular white matter at the upper to middle part of the trigone, while patients with only short-term memory impairment had a lesion in the inferior supramarginal gyrus in common. Thus, damage to the periventricular white matter at the trigone may yield the phonemic paraphasia characteristic of conduction aphasia, while damage to the inferior part of the supramarginal gyrus may result in the impairment of short-term memory. We believe that as a part of the mechanisms of short-term memory and repetition, phonological information is processed in the primary auditory cortex and goes through the periventricular white matter to the inferior part of the supramarginal gyrus and is temporarily stored there.

We describe a clinico-pathological variant of a degenerative disorder involving Broca's, Wernicke's, and supplementary motor areas, which presented as primary progressive aphasia, dysarthria, bucco-facial apraxia, and hearing loss as initial symptoms, followed by organic personality changes. Postmortem examination revealed severe focal atrophy of the cerebral convolutions in the frontal operculum, superior frontal gyrus, and superior and transverse temporal gyri in addition to diffuse atrophy of the frontal and temporal lobes in both hemispheres. Microscopical examination revealed argyrophilic neuronal inclusions (ANIs) in the neuronal perikarya and presynaptic terminal throughout the central nervous system, as well as neuronal loss and swollen chromatolytic neurons in the affected cortices. Neocortical ANIs showed a positive immunoreaction with an anti-tau antibody but only a weak reaction with an anti-ubiquitin antibody immunohistochemically. Ultrastructurally, neocortical ANIs consisted of 15-nm thick smooth-surfaced tubules and tubules with constrictions at 120–150-nm intervals; thus they were different from the typical paired helical filaments of the 80-nm interval constrictions observed in the subiculum. ANIs were also found in the basal ganglia, brain stem nuclei, and cervical cord. Accordingly, ANIs appear distinct from neurofibrillary tangles (NFTs) of progressive supranuclear palsy, NFTs of Alzheimer-type dementia, and Pick bodies. The authors consider that this case fits the histopathological criteria of corticonigral degeneration with neuronal achromasia except for the unusual extension to the temporal lobes.

Objective To clarify the behavioral differences between patients with pure alexia from different lesions. Methods Two patients with pure alexia caused by damage to the fusiform or posterior occipital gyri were given reading and writing tests including kanji (Japanese morphograms) and kana (Japanese phonetic writing). Results Patient 1 (pure alexia from a fusiform gyrus lesion) had difficulty reading both kanji and kana, with kanji reading more impaired, and imageability and visual complexity effects (imageable or less complex words/characters were read better than nonimageable or more complex words/characters), whereas patient 2 (pure alexia from a posterior occipital gyri lesion) showed selective impairment of kana reading. Conclusion Pure alexia for kanji (and kana; fusiform type) is characterized by impairments of both whole-word reading, as represented in kanji reading, and letter identification, and is different from pure alexia for kana (posterior occipital type) in which letter identification is primarily impaired. Thus, fusiform type pure alexia should be designated pure alexia for words, whereas posterior occipital type pure alexia should be designated pure alexia for letters.

Regional cerebral blood flow was measured with H 2 15 O-positron emission tomography during the performance of visually presented calculation tasks to clarify cortical areas involved in arithmetic operations. The findings on a calculation task were compared with those on a covert reading task and with those of a fixation control task. Region of interest-based analysis showed that the left prefrontal area was activated in visual calculation relative to covert reading and the posterior superior temporal gyrus including part of Wernicke's area was activated in calculation relative to fixation control. The role of the prefrontal area in computation (arithmetic operations) and that of the posterior superior temporal gyrus in both comprehension of the stimuli and computation were suggested.