Speech Production • Includes a selection problem: Select from possible words Concept Motor output
Brain Regions for Speech Production • Wernicke’s Area • Broca’s Area • Insula
Wernicke’s and Broca’s are densely interconnected • Connected by white-matter tract called the Arcuate Fasciculus Catani et al. 2005
Aphasia • Much of what we know about language comprehension and production comes from lesion studies • Lesions anywhere in the network (including white matter) can result in complex language deficits
Aphasia • Broca’s Aphasia • Patient “Tan” • Classically thought of as a production deficit • But the sometimes make exclamations and swear !? • Note that Patient Tan’s lesion extended into the insula
Aphasia • Wernicke’s Aphasia • Classically thought of as a comprehension deficit • But lesions to Wernicke’s area result in production deficits: • Non-sensical “word salad”
Aphasias are infamously complex • Why might the clinical picture of aphasia be complicated?