Second Language Acquisition and Second ... - Stephen Krashen

6. The Neurological Correlates of
Language Acquisition: Current
Research
Research and speculation on the neurological correlates of language acquisition have been
growing at a rapid and accelerating rate, and it is increasingly difficult for the nonspecialist to
adequately cover and evaluate current discoveries. This paper will attempt to review some of
the current research in this area, that dealing with what is perhaps the most obvious
neurological phenomenon relating to language, cerebral dominance, or lateralization, and
attempt to update the reader on recent progress and suggest some interpretations of this
research.
Cerebral Dominance
It is by now a well-established finding that for most people (practically all right-handers and
most left-handers), the two sides of the cortex perform different functions. As Table 1
indicates, the left hemisphere
Table 1. Functions of the two hemispheres
________________________________________________________
Left hemisphere Right hemisphere
________________________________________________________
Language Spatial relations
Time-related functions "Gestalt" perception
Part-to-whole judgments
"Propositional" thought Music
"Appositional" thought
________________________________________________________
is responsible for most linguistic performance in adults. Recent studies strongly suggest that
the left brain is also involved in certain non- linguistic functions, specifically those related to
the perception of time: for example, the left hemisphere is superior to the right in judging
temporal order, or deciding which of two stimuli was presented first (see, for example,
Carmon and Nachshon, 1971; Papcun, Krashen, Terbeek, Remington, and Harshman, 1974).
The "other side of the
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