Types of Aphasia

1. Ling 411 – 05 Types of Aphasia

2. Simple Functions / Complex Functions: Speaking and Understanding • How is simplicity/complexity determined? • What about "understanding speech“? • A simple process, localized in Wernicke's area? • Actually it is a pretty complex process • Similarly, “speaking” • Pretty complex, not just Broca's area • Uses not just Broca’s area but also Wernicke’s area • Without a properly functioning Wernicke’s area, • speech is erratic

3. Simple Functions / Complex Functions Complex function Simple function

4. Simple Functions / Complex Functions • Speaking vs. Phonological Production • Phonological production is one part of speaking – located in Broca’s area • Speaking is a complex process • Phonological production plus planning what is about to be produced – involves Wernicke’s area • Understanding speech vs. phonological recognition • Phonological recognition is one part of speech understanding – located in Wernicke’s area • Speech understanding is a complex process • Includes grammatical and semantic activity • Motor activity (Broca’s area) also contributes

5. Basic functions and complex functions – speaking • Phonological recognition is a basic function • Located in Wernicke’s area • along with, perhaps, the area intermediate between primary auditory area and W’s area • Speaking is a complex function • It is a cooperative effort of several areas, including Broca’s area and Wernicke’s area • Phonological recognition is a necessary component of speaking

6. Major Types of Aphasia according to A. Damasio • Wernicke’s aphasia • Broca’s aphasia • Transcortical sensory aphasia • Transcortical motor aphasia • Conduction aphasia • Global aphasia • Anomic aphasia • Alexia with agraphia • Alexia without agraphia • Pure word deafness

7. Wernicke’s Aphasia • Impaired comprehension • Result of failures in phonological discrimination • Fluent verbal output • Augmented verbal output • Extra syllables at ends of words • Extra words at ends of phrases • Extra phrases at ends of sentences • Augmentations usually nonsensical • Syntax otherwise not too bad • Verbal paraphasia, including neologisms

8. Areas of damage in Wernicke’s aphasia • Always involved: • Posterior superior temporal gyrus • The classical core of Wernicke’s area • Usually also involved: • More of superior temporal gyrus • Middle temporal gyrus • Temporal plane* • Often also involved: • Angular gyrus • Supramarginal gyrus • Temporal-occipital junction area *can be considered part of superior temporal gyrus

9. Definitions of Wernicke’s area • Narrow definition • Posterior superior temporal gyrus • Including adjacent temporal plane and superior temporal sulcus • Broad definition (used by some) • Includes also angular gyrus and/or supramarginal gyrus • Better term for this broader area: • ‘Posterior language area’

10. Review Principal cortical gyri (schematic)

11. Subtypes of Wernicke aphasia • Not discretely different • Rather, spans along a scale • Type I • Damage is more anterior • Phonological recognition most affected • “Word deafness” • Type II • Damage is more posterior, incl. angular gyrus • More word-blindness than word-deafness • I.e., alexia • Intermediate types also occur • “Obviously, all subtypes of Wernicke aphasia are variations on a continuum…” • (Benson&Ardila:144)

12. Wernicke’s Aphasia examples http://www.youtube.com/watch?v=B-LD5jzXpLE&feature=related http://www.youtube.com/watch?v=aVhYN7NTIKU

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