The cortical organization of speech processing.
Despite decades of research, the functional neuroanatomy of speech processing has been difficult to characterize. A major impediment to progress may have been the failure to consider task effects when mapping speech-related processing systems. We outline a dual-stream model of speech processing that remedies this situation. In this model, a ventral stream processes speech signals for comprehension, and a dorsal stream maps acoustic speech signals to frontal lobe articulatory networks. The model assumes that the ventral stream is largely bilaterally organized--although there are important computational differences between the left- and right-hemisphere systems--and that the dorsal stream is strongly left-hemisphere dominant.
Hickok
Gregory
G
Department of Cognitive Sciences and the Center for Cognitive Neuroscience, University of California, Irvine, California 92697-5100, USA.
Poeppel
David
D
D001931:Brain Mapping; D002540:Cerebral Cortex / Q000502:physiology*; D006801:Humans; D008960:Models, Psychological; D013060:Speech / Q000502:physiology*; D014705:Verbal Behavior / Q000502:physiology*