Hung Cc

A study on handedness and cerebral speech dominance in right-handed Chinese

Abstract The handedness of Chinese schoolchildren and adults was examined with nine test items; the former group was also surveyed using a questionnaire. The prevalence rate of left-handers was about 3.5% for both schoolchildren and adults. This result strongly suggests that handedness is established in childhood. A study of cerebral speech dominance in 94 right-handed Chinese by means of a Wada test showed that the dominant hemisphere was on the left side in 92 patients and on the right in the remaining two. Thirty of the 94 patients with surgical lesions in the sylvian region were operated upon, and the reliability of the Wada test was demonstrated in each case. It is concluded that in the great majority, but not all, of right-handers the left cerebral hemisphere is dominant for speech. A study of 55 right-handed aphasic patients with surgically verified lesions showed the following: 1. The lesions were invariably found around the sylvian fissure, on the left in 53 and on the right in two. 2. Nominal aphasia was most frequent (32/55), with lesions any where around the Sylvian fissure. 3. Motor aphasia was relatively frequent (20/55), with lesions solely in the anterior sylvian region. 4. Sensory aphasia was rare (3/55), with lesions in the posterior sylvian region. In this study the patients undergoing the Wada test were all, right-handed. No satisfactory explanation for this absence of left-handers has yet been found.

Language processing in bilinguals: Edited by Jyotsna Vaid, New Jersey: Lawrence Erlbaum Associates, Publishers, 1986, xvii + 301 ff.

practitioners will attempt this. At the end of the book, score ratios are given for each of the major aphasia syndromes to show how the test scores can be used for classification if necessary. In conclusion, a tremendous amount of work has gone into making the Bilingual Aphasia Test linguistically and culturally equivalent across 60 pairs of languages (most pairs have English or French). The test is linguistically sophisticated but very lengthy. Even the shortened version as suggested will be impractical for most speech pathologists and the test in its entirety is essentially a research tool. I suspect researchers of bilingualism will find this test filling a needed gap. For the assessment of unilingual aphasics, translations of shorter tests (some are also translated to a substantial number of languages) or only parts of the BAT will be more suitable.

Comments on some papers presented at the first international conference of neurolinguistics

Thank you, Professor Gainotti, for your very interesting and instructive lecture. Although this speech does not give a solution to the whole problem, it does clarify some aspects of the two important types of dementia. It shows, for example, that the patients with Alzheimer’s disease scored si~ificantly worse on measures of immediate recall, delayed recall and delayed recognition. I think most of us will readily accept the interpretation that these results were probably due to a diminished capacity or efficiency of the long-term memory system. This study is neither the beginning nor the end of our research of Alzheimer’s disease and multiinfarct dementia, but rather a powerful impetus to further our investigations.