Language Ref: Banich pp

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

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

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

Two Problems with Classical Model 1.Predicted Patterns Never "Absolute“ 2.Symptoms can dissociate e.g. Wernicke's aphasia: neologisms vs. semantic paraphasiase.g. Wernicke's aphasia: neologisms vs. semantic paraphasias

Current View of Language Linguistics and Cognitive Psychology: language seen as a complex hierarchical system.Linguistics and Cognitive Psychology: language seen as a complex hierarchical system. Can describe language at a number of levels:Can describe language at a number of levels: 1.Phonological: what are the basic phonemes (sound units) used to build words? 2.Syntactic: what are the rules for combining words into sentences? 3.Semantic: what are the meanings of words, and how does meaning change when words are combined in sentences?

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

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

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

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

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

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

Examples of phonemic paraphasias: other examples:castle -> cacksel apron -> aben refrigerator -> redjerfredjer ii. Retrieval of phonemes (cont.) 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...

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

iii. Access to semantic info (cont.) a. Poor word definition: bed: "Bed, bed, I don't know what that is" bed: "Bed, bed, I don't know what that is" swan: "Swan, that sounds familiar, I'm sure I once knew it“ 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?

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

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

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…