Visuographemic alexia: a new form of a peripheral acquired dyslexia.

We report a single-case study of peripherally acquired dyslexia that meets the clinical criteria of "alexia without agraphia." The patient, AA, has a large infarct involving the left posterior cerebral artery. The most striking feature is a severe impairment in recognizing single visually presented letters that precludes explicit or implicit access to reading, even in a letter-by-letter fashion. AA can, however, differentiate letters from similar nonsense characters and digits, and he is also able to identify alphanumeric signs when the visual channel is bypassed (through somesthesic or kinesthesic presentation). Spelling tasks are also well performed. Since there is a breakdown in mapping a visually presented letter to its abstract graphemic representation, we propose the term "visuographemic alexia" for this kind of reading disorder. The pattern of deficits is interpreted following theoretical models previously developed in cognitive neuropsychology. An alexia for arabic numerals with preserved comprehension lends additional support for the crucial processing of different notational systems (e.g., phonographic vs logographic). More general perceptive disorders do not seem to account for these patterns; they are material-specific. Finally, we attempt to specify functional correlations with the implied neural networks.

[Systemic lupus erythematosus starting with deterioration of the higher functions of the central nervous system]. / Lupus eritematoso diseminado comenzando por desestructuración de las funciones superiores del sistema nervioso central.

The authors report the case of a 42 years-old electrician man, with an 8 months progressive manual difficulties in his specific job, with a complete disability for the last 2 months. These symptoms were associated with anemia, deterioration of the general condition, and slight fever. Three days after the first neuropsychological examination he, suddenly, developed a left hemiparesis. Laboratory investigations confirmed the occurrence of a systemic lupus erythematosus. The neuropsychological examination showed: normal intellectual level with slight memory deficit; severe constructional and ideomotor apraxia; gaze ataxia; optical ataxia; hemisomatoagnosia, anosognosia, and autotopagnosia; agraphia. The authors discuss this particular syndromatic association, remarking the alterations of oculomotor control, the optical ataxia and the role which both may have in the disorganization of gesture activity, concerning also the gnosics disturbances. Furthermore, agraphia is stressed as well as its relation with apraxic disturbances. On the basis of the semiological analysis, the authors come to the conclusion of a bilateral temporo-parieto-occipital involvement.