RECOVERY FROM NONFLUENT APHASIA AFTER MELODIC INTONATION THERAPY - A PET STUDY

We examined mechanisms of recovery from aphasia in seven nonfluent aph asic patients, who were successfully treated with melodic intonation t herapy (MIT) after a lengthy absence of spontaneous recovery. We measu red changes in relative cerebral blood flow (CBF) with positron emissi on tomography (PET) during hearing and repetition of simple words, and during repetition of MIT-loaded words. Without MIT, language tasks ab normally activated right hemisphere regions, homotopic to those activa ted in the normal subject, and deactivated left hemisphere language zo nes. In contrast, repeating words with MIT reactivated Broca's area an d the left prefrontal cortex, while deactivating the counterpart of We rnicke's area in the right hemisphere. The recovery process induced by MIT in these patients probably coincides with this reactivation of le ft prefrontal structures. In contrast, the right hemisphere regions ab normally activated during simple language tasks seem to be associated with the initial persistence of the aphasia. This study supports the i dea that abnormal activation patterns in the lesioned brain are not ne cessarily related to the recovery process.