THE NONINVASIVE IDENTIFICATION LANGUAGE FUNCTION - NEUROIMAGING AND RAPID TRANSCRANIAL MAGNETIC STIMULATION

Neuroimaging techniques that rely on detecting alterations in blood fl ow may be used to map the cortical localization of cognitive function during task performance. O-15 water positron emission tomography studi es have mapped neural networks that subserve language function. These techniques have been adapted to lateralize and localize language funct ion in patients with intractable epilepsy prior to epilepsy surgery. F unctional magnetic resonance (fMR) imaging, relying upon fast MR imagi ng techniques performed during cognitive tasks, allows localization of language areas in individual adults and children and, because there i s no radiation exposure, allows for additional or repeat studies in pa tients. These noninvasive means of language localization may supplant the invasive means of language lateralization (intracarotid amytal pro cedure) and localization (corticography), and will allow for the conti nued study of language organization in health and disease.