Number processing after stroke: anatomoclinical correlations in oral and written codes.

Calculation and number-processing abilities were studied in 49 patients with chronic single vascular brain lesions by means of a standardized multitask assessment battery (EC301), as well as through other tasks, testing functions thought to be implicated in calculation such as language, visuo-perceptive abilities, verbal and spatial working memory, planning, and attention. The results show that (1) lesions involving parietal areas-particularly left parietal lesions-are prone to alter calculation processing. A more detailed analysis showed that patients with lesions involving left parietal areas were impaired in both digital (i.e., comprehension and production of numbers written in Arabic code) and oral (i.e., comprehension and production of numbers heard or expressed orally) processing while lesions involving right parietal areas lead to an impairment in digital processing only. However, linguistically related alphanumerical processing (i.e., comprehension and production of numbers written orthographically) was not influenced by parietal lesions. (2) Semantic representations (knowledge of the magnitude related to a given number) as well as rote arithmetical knowledge are also impaired following damage to parietal and particularly left parietal lesions, suggesting that these areas are also implicated in magnitude comparisons and in the retrieval of arithmetical facts. (3) Performance in calculation is highly correlated with language. (4) Moreover, we found a highly significant correlation between performances in oral calculation and verbal working memory, and between written-digit calculation and visuospatial working memory. Performances in regard to visuo-perceptive abilities, planning, and attention were less consistently correlated with calculation. These results stress the close correlation, but relative independence between calculation and language, as well as a dissociated sensitivity of oral and digital processing to brain lesions.

Cognitive consequences of early phase of literacy.

The effect of the degree of illiteracy (complete or incomplete) on phonological skills, verbal and visual memory and visuospatial skills is examined in 97 normal Brazilian adults who considered themselves illiterate, and 41 Brazilian school children aged 7 to 8 years, either nonreaders or beginning readers. Similar literacy effects were observed in children and in adults. Tasks involving phonological awareness and visual recognition memory of nonsense figures distinguish the best nonreaders and beginning readers. Children performed better than adults at oral repetition of short items and figure recall, and adults better than children at semantic verbal fluency, digit span, and word list recall. A principal component analysis of the correlations between tasks showed that phonological awareness/reading, phonological memory/oral repetition, and semantic verbal memory/fluency tasks, generated different components. The respective role of culturally based preschool activities and literacy on the cognitive functions that are explored in this study is discussed.

Subjective experience after stroke.

To assess subjective experience after stroke, 214 patients completed the 63-item European Brain Injury Questionnaire. The same questionnaire was also completed by a close relative of each patient and by 214 control participants matched for gender and age. A principal component analysis showed 3 factors: depressive mood, cognitive difficulties, and difficulties in social interactions. In self-assessment, whereas the first 2 factors were scored higher by patients than by controls, the level of difficulty in social interactions did not differ between these 2 groups. In hetero-assessment, relatives scored patients' difficulties higher than patients did, especially for items suggesting the impact of stroke on themselves. Psychological difficulties of stroke patients and the consequences on their relatives need to be taken into account in rehabilitation programs.