1 / 18

Language

Language. Ref: Banich pp. 361-364. Broca's Aphasia: Typical Features. Slowed, effortful speech, with many pauses Poor articulation Speech may be telegraphic Comprehension largely preserved. Wernicke's Aphasia: Typical Features. Fluent, well articulated speech, function words

newman
Télécharger la présentation

Language

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Language Ref: Banich pp. 361-364

  2. Broca's Aphasia: Typical Features • Slowed, effortful speech, with many pauses • Poor articulation • Speech may be telegraphic • Comprehension largely preserved

  3. Wernicke's Aphasia: Typical Features • Fluent, well articulated speech, function words • May sound “empty” of content • Word substitution errors: • phonemic paraphasias e.g. castle -> "cacksel" • semantic paraphasias e.g. camel -> "horse" • neologisms e.g. queen -> "robbli” • Comprehension impaired

  4. Classical Model of Language • Broca's area = production ("articulatory images" of words) • Wernicke's area = comprehension ("auditory images") • Info is transmitted between the two:

  5. Two Problems with Classical Model • Predicted Patterns Never "Absolute“ • Symptoms can dissociate • e.g. Wernicke's aphasia: neologisms vs. semantic paraphasias

  6. Current View of Language • Linguistics and Cognitive Psychology: language seen as a complex hierarchical system. • Can describe language at a number of levels: • Phonological: what are the basic phonemes (sound units) used to build words? • Syntactic: what are the rules for combining words into sentences? • Semantic: what are the meanings of words, and how does meaning change when words are combined in sentences?

  7. Current View of Language • By this view, speech production and comprehension not unitary processes, but involve multiple components. For example: • Production = syntactic planning, word selection, retrieval of phonemes, articulatory programming • Comprehension = auditory processing, access to word meanings, syntactic processing.

  8. Current View of Language • For many individuals, syndromes don’t work • Therefore, some researchers now prefer the terms Fluent and NonfluentAphasia: Nonfluent aphasia: • Anterior damage (usually) • Covers Broca’s aphasia, as well as P’s with just one or two features Fluent aphasia: • Posterior damage (usually) • Covers Wernicke’s aphasia, as well as P’s with just one or two features

  9. Some Language Components All of these can become selectively impaired: • Anterior (around Broca’s area): • Articulation of speech • Understanding syntactic relationships • Posterior (around Wernicke’s area): • Retrieval of phonemes for production • Selection of words for production • Access to semantic info about words

  10. Some Language Components All of these can become selectively impaired: • Anterior (around Broca’s area): • Articulation of speech • Understanding syntactic relationships • Posterior (around Wernicke’s area): • Retrieval of phonemes for production • Selection of words for production • Access to semantic info about words

  11. i. Articulation of speech • Function of this Component: • Generation of motor programs or articulating words • Location: • Overlaps with Broca’s area • Effects of Damage: • Speech is halting, effortful • Words may sound distorted • P knows the sounds in words, but can't articulate

  12. ii. Retrieval of phonemes • Function of this Component: • Retrieval of stored info. about the sounds that make up words • Location: • Posterior: close to (partially overlapping?) Wernicke’s area • Effects of Damage: • P can articulate well • BUT don't know which sounds to articulate • Phonemic paraphasias in all speech situations…..

  13. ii. Retrieval of phonemes (cont.) Examples of phonemic paraphasias: um.. tornet, no that's not right.. t-.. turry-.. no.. turkey.. no... oh gosh.. tur-.. turk-... turking.. that's wrong what's the end part?.. um.. I can't remember... other examples: castle -> cacksel apron -> aben refrigerator -> redjerfredjer

  14. iii. Access to semantic info • Function of this Component: • Accessing word meanings • Involved in both production and comprehension • Location: • Posterior -> temporal lobe, some overlap with Wernicke’s area • Effects of Damage: • P can’t define words • Can’t match a word to its meaning • Semantic paraphasias in speech...

  15. iii. Access to semantic info (cont.) a. Poor word definition: bed: "Bed, bed, I don't know what that is" swan: "Swan, that sounds familiar, I'm sure I once knew it“ b. Failure at word-picture matching: Which is a picture of a newspaper?

  16. iii. Access to semantic info (cont.) c. Semantic paraphasias in speech and naming: That’s some kind of animal, isn’t it. A seal, is it? other examples: camel -> horse son -> daughter walking -> running

  17. Anterior vs. posterior language areas • This is broken here! e.g. phoneme retrieval - posterior region, but affects output more examples in later lectures… • How do we explain this? • The general rule: • Anterior = output • Posterior = input

  18. Anterior vs. posterior areas (cont.) Anterior regions are involved in: Generation of new combinations e.g. sentences (novel combinations of words) articulation (must be done afresh each time) • Posterior language regions (LH) are involved in: • Storage/retrieval of familiar, well-learned relationships • e.g. phoneme sequences of common words • meanings of common words More about anterior/posterior differences in upcoming lectures…

More Related