Language in the Nondominant Right Hemisphere

Abstract

• Language function was evaluated in the right nondominant hemisphere in three patients undergoing cortical resection for intractable seizures. Three linguistic tests were given during electrical stimulation of the cortex. They represented three different levels of language complexity from lowest to highest as follows: task 1, object naming; task 2, sentence completion; and task 3, responsive naming. The greatest number of linguistic errors occurred with sentence completion. No linguistic errors were made on the most complex task. Wada's test in the right nondominant hemisphere did not impair function, whereas in the left dominant hemisphere it did. To make these seemingly incompatible observations acceptable, we speculate that there is a right nondominant language system that is anatomically and functionally tied to the left dominant system. Under normal conditions it is passively involved and its integrity is not essential to the function of the left dominant language system.