Second Language Acquisition and Second ... - Stephen Krashen

The Role of the Right Hemisphere in Second Language Acquisition
We turn now to a slightly different but related topic, one that has also stimulated a great deal of
interest recently: the role of the right hemisphere in second language acquisition. The position
we outlined for first language acquisition is consistent with the idea that the right hemisphere
may play some role in early stages, and interestingly enough, it has been suggested that the right
brain is somehow involved in normal second language acquisition in much the same way. Again,
we briefly list some recent research results in this area, and attempt to supply an explanation.
1. Brain damage. In a recent survey of aphasia in "polyglot" subjects, Galloway (forthcoming)
found a slightly higher incidence of aphasia due to right-sided lesions than in a presumable
monolingual population (Table 2), consistent with the idea that the right hemisphere might be
playing some role in second language acquisition or performance.
Table 2. Frequency of aphasia in polyglots and monolinguals
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Right-handers Left-handers
polyglots monolinguals* polyglots monolinguals*
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Right lesions 4 (14%) 2% 5 (71%) 32%
Left lesions 25 (86%) 98% 2 (29%) 68%
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* Estimated from aphasia literature (Galloway, forthcoming).
2. Dichotic listening and tachistoscopic exposure. Some dichotic listening studies and some
tachistoscopic exposure studies (a visual analogue of dichotic listening: response superiority for
items flashed to the right visual field is interpreted as reflecting left hemisphere processing)
show little or no difference between first and second languages, typically showing left
hemisphere processing for both (Hamers and Lambert, 1977; Barton, Goodglass, and Shai, 1965;
Kershner and Jeng, 1972; Carroll, 1978). Other studies, however, do show the second language
to be less left hemisphere lateralized or show right hemisphere processing. Obler, Albert, and
Gordon (1975), in a study of Hebrew-English bilinguals, found a right-ear advantage for both
Hebrew and English words, but observed a greater right-ear
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