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Language & the Brain. Ling 001-03 Fall 2010. Special topics: -Autism -Aphasia. Neuroanatomy (basic). Hemispheres (Left & Right). Lateralization : Different hemispheres are responsible for different functions.
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Language & the Brain Ling 001-03 Fall 2010 Special topics: -Autism -Aphasia
Hemispheres (Left & Right) • Lateralization: Different hemispheres are responsible for different functions. • Contralateralization: The L side of the body is controlled by the R side of the brain, and vice versa. • Corpus callosum: Bundle of nerves that allow the two hemispheres to communicate with one another. Split brain patients: People in whom the corpus collosum has been severed (keep in mind for object-naming task. Corpus callosum
Controls the R side of the body. Contains the language center (for R-handed, over 90%; for L-handed, about 70%). Syntax (grammar), lexicon, language comprehension. Handles analytical thought processes: arithmetic, temporal ordering. Controls the L side of the body. Manages understanding mental states (theory of mind). Processes nonliteral meaning (sarcasm, metaphors, etc.). Emotion, affect, social inhibition/disinhibition. Handles perception of nonlinguistic sounds (e.g. music). Left & Right Brains Left Right TEST: Object-naming experiment. Video
Linguistics in the Brain What happens when we produce a word? • Wernicke's area: activated when accessing the lexicon. • Arcuate fasciculus: phonetic information sent from Wernicke's area to Broca's area. • Broca's area: interprets information received from the arcuate fasciculus; transmits articulatory information to the motor cortex. • Motor cortex: directs movement of the muscles for articulation.
Linguistics in the Brain What happens when we hear a word? • Auditory cortex: processes information perceived by the ears. • Wernicke's area: interprets auditory stimulus, and matches information to a lexical entry.
Dichotic listening Right hemi Left hemi Corpus callosum Verbal stimulus Left ear Right ear
Developmental language impairments • Brief survey of Down Syndrome, Williams Syndrome • Discussion of Autism
Language impairments (developmental) from "Frog, Where are You?" by Mercer Mayer, 1969.
Down Syndrome • Down Syndrome subject, age 18, IQ 55: "The frog is in the jar. The jar is on the floor. The jar on the floor. That's it. The stool is broke. The clothes is laying there."
Down Syndrome: Characteristics • Language: • Delayed relative to chronological age, consistent relative to mental age, up to age 3-4. • Phonological development delayed into adulthood. • Lexical development lags behind mental age. • Grammatical development lags behind mental age and proceeds slowly through adulthood. • MLU stalls at 3.0. • Some pragmatic abilities (turn-taking) intact. • Difficulties in reference and politeness. • Cognition: • IQ typically less than 50. • Cognitive facilities (mental age) ahead of language development.
Williams Syndrome • Williams Syndrome subject, age 17, IQ 50: "Once upon a time when it was dark at night, the boy had a frog. The boy was looking at the frog, sitting on the chair, on the table, and the dog was looking through, looking up to the frog in a jar. That night he sleeped and slept for a long time, the dog did. But the frog was not gonna go to sleep. The frog went out from the jar. And when the frog went out, the boy and the dog were still sleeping. Next morning it was beautiful in the morning. It was bright, and the sun was nice and warm. Then suddenly when he opened his eyes, he looked at the jar and then suddenly the frog was not there. The jar was empty. There was no frog to be found."
Williams Syndrome: Characteristics • Language: • Good language abilities: syntax, lexicon, cohesion in narrative. • Language development is delayed, but once it accelerates, it catches up. • Language scores are equal to or above mental age, but lower than chronological age. • Some pragmatic difficulties (emotion, drama in narrative). • Cognition: • IQ typically less than 70 (similar to Down Syndrome). • Excessively social. • Poor fine motor and spatial skills (drawing, etc.).
Autism • Various autistic subjects, children: "An' the baby was crying. The frog was trying to get away." "An' the cat just look up an' the frog just look at the baby an' the baby was just frowned at the frog." "An' the cat is trying to get the frog an' the baby is crying."
Autism: Characteristics • Language: • Low-functioning: either no speech, or echolalia. • High-functioning: deviant prosodic features, normal semantics, slightly delayed syntax. • Limited use of mental state verbs. • Pragmatic problems (pronouns, cohesive discourse, indirect requests). • Cognition: • Significant differences between high- and low-functioning people with autism (spectrum). • Problems with joint attention. • Severely delayed theory of mind.
Common diagnostic criteria pertaining to language (Landa, 2007): • Either significantly delayed onset of spoken language (or total absence) • Impaired patterns of conversational initiation and response • Stereotypical and repetitive use of any language skills • Lack of imaginative or socially imitative play appropriate for the child's developmental level
Social & communicative impairments: JOINT ATTENTION • Difficulty orienting to or attending to a communicative partner • Difficulty flexibly shifting eye gaze between people and objects • Difficulty following the gaze or pointing of others • Difficulty getting the attention of others in order to initiate an interaction • Note: Children who are more responsive to attempts to engage them have a better prognosis for developing expressive language
Eye gaze / attention White crosses = typical child Black crosses = child with autism
Eye gaze / attention White trace = typical child / Black trace = child with autism Reference: Klin, A., Jones, W., Schultz, R., & Volkmar, F. (2003). The Enactive Mind, or From Actions to Cognition: Lessons from Autism. Philosophical Transactions of the Royal Society of London B, 358, 345-360.
Social & communicative impairments: THEORY OF MIND • Lack of theory of mind, or "mindblindness" (Baron-Cohen) • While typical children follow the eye gaze of speakers in order to map new words to objects, children with autism can only attend to their own visual field Video
Linguistic impairments • Phonetics/phonology • Good articulation • Trouble with suprasegmental features • Morphology/syntax • Development is delayed, but follows normal patterns • Relatively narrow range of constructions used • Reduced use of forms, like questions, that initiate interaction • Reduced use of matrix clauses, mental state verbs • Reversal of pronouns (using you instead of I)… why? • Pragmatics • Echolalia Video Video
Acquired language impairments • Discussion of Aphasia
What is aphasia? • The impairment of linguistic capability resulting from brain damage. • Usually occurs suddenly, as the result of a stroke or head injury, but it may also develop slowly, as in the case of a brain tumor or dementia. • Impairs the production and comprehension of language as well as reading and writing. • May co-occur with speech disorders such as dysarthria or apraxia of speech, which also result from brain damage.
Brains MRI (magnetic resonance imaging): an imaging technique that uses magnetic fields to take pictures of the structure of the brain. CT (computerized tomography): a scan that creates a series of cross-sectional X-rays of the head and brain; also called computerized axial tomography or CAT scan. MRI; lesion on L side. CT; large stroke on R side. TMS (transcranial magnetic stimulation): a technique in which a change in magnetic fields creates weak electronic currents which excite the neurons in the brain. Video
Broca's aphasia • Phonetics/phonology: • Formation of sounds is laborious, clumsy • Morphology/lexicon: • Vocabulary access limited, trouble with inflection • Syntax: • Often agrammatic ("telegraphic"), reduced to short utterances lacking function words • Other: • Comprehension of speech is relatively good, reading is relatively good, but writing might be limited. Broca's aphasia is often referred to as a "nonfluent aphasia" because of the halting and effortful quality of speech Video
Wernicke's aphasia • Phonetics/phonology: • Formation of sounds is typically normal • Morphology/lexicon: • Instances of jargon/neologisms • Syntax: • Grammar may be normal, but sentences do not connect to each other cohesively; irrelevant words intrude • Other: • Ability to grasp the meaning of spoken words is chiefly impaired, while the production of connected speech is not much affected; often called "fluent aphasia". Reading and writing are often severely impaired. Video
Describing aphasia • Paraphasia: The production of incorrect sounds, syllables, words, or phrases. • Phonemic: the wrong word and the target word sound similar, e.g. calling a ball a tall. • Semantic: the meaning of the wrong word is related to the meaning of the target, e.g. using the word briefcase for suitcase. • Neologistic: less than half of the target word is produced correctly, e.g. calling a bubble a toggle. • Perseveration: Uncontrolled repetition of a particular response (sounds, syllables, words, gestures) when the stimulus is no longer present. Can also occur in writing.
Describing aphasia • Anomia: Inability to name, or recognize the names of, objects. • Circumlocution: The substitution of another word or phrase or gesture in place of a word that cannot be evoked, e.g. watch is described as the thing that you use to tell time.
What’s happening in this picture? Goodglass, H., & Kaplan, E. (1972). The Assessment of Aphasia and Related Disorders. Philadelphia, PA: Lea & Febiger.
RW: 80? y.o. F, LCVA, dx __ Alright, we’ll talk about the two children, there are the a sleak…..sneaking some cookies… from the cookie jar and the little boy is going to g… get up on the a…a the r… height so that he’s gonna get on this little stool. And the stool is about going to crash down on the floor a… with him in it. And that’s his s s s… sister is probably directing… what is the action. And the fath… the um the sis..sist, the mother is now very…ha (laugh) she’s ….subconscious. She doesn’t see that the faushis…faucet in the, in the uh…skint…sink is over… overflow with the sink. And now the water is getting into…onto the floor. And she is dreamily…. drying a…uh either a platter or something big plate and she’s got some uh looks like tor… tow…uh mi…dish… dishtower to uh…um looking at the looking in the the um power…the…the open is the the where they…I don’t know what is that, this here? What would you say (pointing to the bush)? But anyway I don’t… not important. It’s very good. She’s got um…it’s a un..un…under..ummer day…no um it’s a warn…warm…weather um…day with the open is on or they… the um weather is good. And what else can I tell you…and she’s very s..s..sa..she’s unconscious of course..she’s got her take the take show her s..her shoes are in the peddle tuddle…I can’t do it anymore.
RW: 80? y.o. F, LCVA, dx Wernicke’s Alright, we’ll talk about the two children, there are the a sleak…..sneaking some cookies… from the cookie jar and the little boy is going to g… get up on the a…a the r… height so that he’s gonna get on this little stool. And the stool is about going to crash down on the floor a… with him in it. And that’s his s s s… sister is probably directing… what is the action. And the fath… the um the sis..sist, the mother is now very…ha (laugh) she’s ….subconscious. She doesn’t see that the faushis…faucet in the, in the uh…skint…sink is over… overflow with the sink. And now the water is getting into…onto the floor. And she is dreamily…. drying a…uh either a platter or something big plate and she’s got some uh looks like tor… tow…uh mi…dish… dishtower to uh…um looking at the looking in the the um power…the…the open is the the where they…I don’t know what is that, this here? What would you say (pointing to the bush)? But anyway I don’t… not important. It’s very good. She’s got um…it’s a un..un…under..ummer day…no um it’s a warn…warm…weather um…day with the open is on or they… the um weather is good. And what else can I tell you…and she’s very s..s..sa..she’s unconscious of course..she’s got her take the take show her s..her shoes are in the peddle tuddle…I can’t do it anymore.
MP: 59 y.o. F, LCVA, dx __ Oh …oh yes… oh oh oh (pointing to water overflowing) do-to-do (sing-song like)…oh yeah ooh uh oh…yeah yeah yeah fine…um um do (sound effect/sing song quality that she often uses “do-to-do”) yeah… >Clinician: can you use any words to describe it? Oh oh uh cho..colate pour pour um um yeah uh oh…ooh. >Clinician: any more words? Cookie…um pour…pour pour um yeah fine uh oh uh oh…
MP: 59 y.o. F, LCVA, dx Broca’s / severe nonfluent Oh …oh yes… oh oh oh (pointing to water overflowing) do-to-do (sing-song like)…oh yeah ooh uh oh…yeah yeah yeah fine…um um do (sound effect/sing song quality that she often uses “do-to-do”) yeah… >Clinician: can you use any words to describe it? Oh oh uh cho..colatepour pour um um yeah uh oh…ooh. >Clinician: any more words? Cookie…um pour…pour pour um yeah fine uh oh uh oh…
JL: 48 y.o. M, TBI, dx __ Three people are involved. The parent and ah…s…um…part...peep…two people she got a man and a woman. The man…gots… gets on a chair that’s falling… when he stands on it and he gets… stuff out to eat from the cabinet… and he’s giving the woman something to eat but he’s describing what he has… he’s called it…XX… a name… and he can hold it in one hand…his woman is replying with one hand on her mouth… and the other hand stretches up to him waiting for something to be given her… and he’s standing in the air… looking for this in a.. common wa...where..where… the where it’s put in the air. On this side is the wife… is his mother and her mother or probably the mo..mother she’s… has something in her hand… ands…which you can eat with. In the other hand she has…has..something which hangs which she can dry with. Outside… is a place with she can see… th..where the where they live…huh…um…then there’s something which you can use to wash… it’s used XXX using liquid or air and it’s too full and it’s running out and…fffalling on the ground… and close to her are.. one, two things you can drink with… and a third thing which you can use at the bottom….out…outside is a…a…pplace of where she’s staying… and things that are grown…growing…the place through which she looks has these two…th..things that fold up and on the s…ide of the…are two…of… these things… so the man…the boy is in the air his son is standing on the air on the ground his wife is also…but anyway that’s about it.
JL: 48 y.o. M, TBI, dx fluent aphasia w anomia and comprehension deficits Three people are involved. The parent and ah…s…um…part...peep…two people she got a man and a woman. The man…gots… gets on a chair that’s falling… when he stands on it and he gets… stuff out to eat from the cabinet… and he’s giving the woman something to eat but he’s describing what he has… he’s called it…XX… a name… and he can hold it in one hand…his woman is replying with one hand on her mouth… and the other hand stretches up to him waiting for something to be given her… and he’s standing in the air… looking for this in a.. common wa...where..where… the where it’s put in the air. On this side is the wife… is his mother and her mother or probably the mo..mother she’s… has something in her hand… ands…which you can eat with. In the other hand she has…has..something which hangs which she can dry with. Outside… is a place with she can see… th..where the where they live…huh…um…then there’s something which you can use to wash… it’s used XXX using liquid or air and it’s too full and it’s running out and…fffalling on the ground… and close to her are.. one, two things you can drink with… and a third thing which you can use at the bottom….out…outside is a…a…pplace of where she’s staying… and things that are grown…growing…the place through which she looks has these two…th..things that fold up and on the s…ide of the…are two…of… these things… so the man…the boy is in the air his son is standing on the air on the ground his wife is also…but anyway that’s about it.
Sign language and aphasia SIGN LANGUAGE PROCESSING AND THE MIRROR NEURON SYSTEM David P. Corina and Heather Knapp, (Department of Psychology, University of Washington, Seattle, WA, USA), Cortex, (2006) 42, 529-539. Fig. 1 – Examples of errors following stimulation to Broca’s area (BA 44). Shown are location of stimulation, the naming stimuli, the intended handshapes required for the correct sign name of the object, and S.T.’s resulting handshape.
Sign language and aphasia Fig. 2 – Examples of errors following stimulation to SMG (BA 40). Shown are location of stimulation, the naming stimuli, the intended handshapes required for the correct sign name of the object, and S.T.’s resulting handshape.
Further study • American Speech-Language-Hearing Association (ASHA) page on aphasia: www.asha.org/public/speech/disorders/Aphasia.htm • Harold Goodglass Aphasia Research Center: http://www.bu.edu/aphasia/index.html • National Aphasia Association: www.aphasia.org • NIH website on aphasia: www.nidcd.nih.gov/health/voice/aphasia.htm