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The case is described of a patient with alexia and agraphia for kanji, and severe anomia after a subcortical haemorrhage in the left posterior inferior temporal area. Magnetic resonance imaging at four months after onset showed a lesion in the inferior temporal and fusiform gyri, extending from the temporo-occipital junction toward the anterior third of the temporal lobe. Comparison with other reported cases of alexia with agraphia and anomia made it clear that when accompanied by severe anomia, the lesions extended either forward to the anterior part of the middle temporal gyrus or medially to the parahippocampal gyrus. It is suggested that the disconnection of association fibres between the parahippocampal, fusiform, middle, and inferior temporal gyri, especially between the parahippocampal gyrus and the other temporal gyri, or the cortical damage to the posterior part of these gyri is essential for the production of anomia.

The reading of four subjects suffering from a phonological reading impairment as a result of a cerebral lesion was tested. A double dissociation observed in their results is strong evidence for the existence of two functionally independent kinds of phonological processing in reading--a graphemic and a phonetic one.

Three dissociations were observed in a case of alexia: a disturbance of reading, without comparable disturbance of oral expression, oral comprehension, writing, or spelling aloud; a disturbance of the phonological reading process, without disturbance of the non-phonological reading process; a disturbance located at the level of the phonological stage, without disturbance of the perceptual and expressive stages. This pattern of results has been called phonological alexia.

A deep dyslexic patient was tested on a series of experiments designed to assess her comprehension of abstract words. On tests where a precise semantic representation of words was required, performance was much poorer with visual than with auditory presentation. However, on some but not all categorisation tests performance with both modalities was good. It is argued that deep dyslexia can result from a modality-specific deficit in attaining the meaning of words together with a disorder of the phonological reading route.

Aphasic patients were given tests assessing pantomime recognition, reading comprehension, aural comprehension, and naming ability to determine whether defective pantomime recognition could be the result of a disturbance of symbolic thinking also affecting linguistic functioning. Defects in pantomime recognition always occurred in conjunction with reading defects of at least comparable severity, but reading defects sometimes occurred without comparable defects in pantomime recognition. The relationship of pantomime recognition with both aural comprehension and naming ability was significantly weaker than that between pantomime recognition and reading comprehension. The implications of the findings with regard to other nonverbal aphasic symptoms and the role of sensory modality factors are discussed.

A 59-year-old, right-handed, college-educated male examined after stroke presented spelling alexia with relative sparing of writing. He was not aphasic. A striking feature of the alexia was preserved recognition of letters printed in view by the clinician. He was able to read words through letter-by-letter oral spelling when letters were presented in this dynamic fashion. We describe this as a dynamic form of spelling alexia. Head CT scan showed a large left hemisphere posterior lesion infringing on the corpus callosum, and a right hemisphere opercular lesion. We suggest that sparing of the right parietal-occipital cortex may contribute to the remarkable sparing of dynamic letter reading.