Language processing – role of inferior parietal lobule

Abstract

Summary: It has long been known and demonstrated that activation of Wernicke’s area causes simultaneous activation of Broca’s area and the premotor frontal cortex via the arcuate fasciculus. Such simultaneous activation occurs in other areas, as well. One of those areas is the lower parietal cortex, which consists of the supramarginal and angular gyri. The supramarginal gyrus acts to analyze phonological properties of words and to merge syllables into words. It is consequently considered to be part of the Wernicke area by many authors. The angular gyrus is surrounded by secondary somatosensory, visual and auditory cortical areas and is essential in multimodal, highly complex synthesis of information. This is evident in both lesion studies, showing disturbed semantic processing in angular gyrus damage, and functional imaging studies showing angular activation in complex sentence structure interpretation.