the study of the neurological mechanisms underlying the storage and processing of language. Although it has been fairly satisfactorily determined that the language centre is in the left hemisphere of the brain in right-handed people, controversy remains concerning whether individual aspects of language are correlated with different specialized areas of the brain. One kind of research carried on in this field is the study of aphasia, a condition of the brain in which language ability is impaired or destroyed. Temporary aphasia has been induced by electrically stimulating the cortex of conscious patients in order to determine the location of the various functions of language. Although very general centres of language have been proposed, it seems that there are no highly specialized centres. Several cases have been reported of patients who, after having their left hemisphere of the brain removed, adapted in the right hemisphere the language function that the left hemisphere had had. In general, however, though progress is being made in this field, very little is known for certain about the neurological aspects of language.