Lecture 1: Language and the Brain

Question 1

Kirby et al. (2008) (4)

Answer 1

• Human speech tends towards structure.
• AI learning task with multiple iterations.
• Participants matched words to a ball’s color, shape, and motion.
• After 100 iterations, produced a pattern similar to language.

Question 2

special populations (1)

Answer 2

• Groups of individuals who have some sort of language impairment.

Question 3

double dissociation (2)

Answer 3

• In psycholinguistics: when language is impaired but other cognitive skills are normal, or when language is normal despite impairment of other cognitive functions.
• Provides evidence for brain modules/specialization.

Question 4

aphasia (1)

Answer 4

• Any language disruption or deficit caused by brain damage (either from stroke or external puncture).

Question 5

Broca’s aphasia (5)

Answer 5

• Aphasia characterized by halting speech and difficulty in choosing words, but good comprehension.
  
  • Often simplify consonant clusters, use consonant fortition and telegraphic speech, and unable to judge acceptability of sentences.
• Caused by lesion to left inferior frontal gyrus (Broca’s area).
• Perception and comprehension are (mostly) intact.
• Patients are aware of deficit and it’s often frustrating.

Question 6

Wernicke’s aphasia (4)

Answer 6

• Aphasia associated with fluent, well-articulated speech that’s often nonsensical, and difficulty understanding language.
  
  • Phonological production (prosody, consonants/vowels, syntax) all fine.
• Caused by lesion to posterior part of the superior temporal gyrus (Wernicke’s area).
• Patients generally unaware of the deficit.

Question 7

Broca-Wernicke model (4)

Answer 7

• Language is in the left side of the brain.
  
  • Lesions to the right hemisphere analogs of Broca’s and Wernicke’s areas rarely (if ever) result in language deficits.
• Extremely simple compared with complexity involved in human language processing and production.
• Current models propose broader, more distributed networks of language areas.

Question 8

brain lateralization (1)

Answer 8

• The specialization of the brain’s right and left cerebral hemispheres for different functions.

Question 9

dichotic listening (3)

Answer 9

• Subjects listen to spoken words over headphones, with a different word spoken into each ear.
• Demonstrates brain lateralization in non-split-brain patients.
• right ear advantage (REA): Hearing info in the right ear more easily—since it travels to the left hemisphere (the presumed seat of language).

Question 10

Kimura (1961) (2)

Answer 10

• Normal and lesioned participants listen to sequence of 6 digits in either left or right ear.
• Recalled digits; normal participants have higher accuracy when info is presented through the right ear.

Question 11

split-brain patients (4)

Answer 11

• Epileptic patients often have corpus callosum severed to treat seizures.
• Left and right hemispheres can’t communicate.
• Unable to name pictures or read aloud words presented to right hemisphere.
• Can communicate identity of object using left hand.

Question 12

language in the right hemisphere (3)

Answer 12

• Intonation, prosodic and melodic aspects, metaphors and jokes, and language in social context are processed by right side.
• 40% of lefties have bi-lateralized language.
• Damage to left hemisphere as infant → neuroplasticity relocates functions to right hemisphere.

Question 13

domain-specific perspective (4)

Answer 13

• Processes and representations in language specific to language (i.e. not shared with other domains).
• Evidence for domain-specificity;
  
  • SLI and Family K: disorders in language abilities where cognition stays intact.
  • WMS: cognitive impairment where language abilities stay intact.
  • But the data isn’t so clear-cut.

Question 14

domain-general perspective (1)

Answer 14

• Processes and representations in language not specific to language (i.e. shared with memory, attention, vision, IQ, etc.).

Question 15

specific language impairment (SLI) (5)

Answer 15

• Children fail to develop language normally without neurological damages, cognitive impairment, or hearing loss, and no abnormal home environment that could explain this failure.
• Often produce language later than peers.
• Difficulties at multiple levels of linguistic representations/processes.
• Similarities to Broca’s aphasia: 1) simplify consonant clusters, 2) can’t phonologically decompose words, 3) can’t perceive subtle differences in sounds.
• Broad category of language deficits; doesn’t necessarily mean cognitive deficits.

Question 16

wug test (2)

Answer 16

• “This is a wug. Now there are two of them. There are two ____.”
• Children with SLI can’t answer this.

Question 17

Family K (5)

Answer 17

• A case of SLI in adults; SLI usually disappears after childhood.
• Around 30 family members over three generations, some had speech deficits (to varying degrees) while others didn’t.
• Those affected displays symptoms typical of SLI.
• Discovered that there was a disorder on Chromosome 7 with the FOXP2 gene.
  
  • But this gene controls many other developmental pathways too, which means that we can’t necessarily call it the “language gene.”

Question 18

Williams syndrome (WMS) (3)

Answer 18

• Genetic syndrome (anomaly on Chromosome 7); language function relatively preserved despite more seriously impairments in other areas of cognitive function.
• Have difficulty with numerical terms, spatial organization, everyday tasks, and have an IQ around 50-55.
• Can still produce complex sentence structures with no grammatical or phonological errors.

Question 19

Bellugi (2000) (4)

Answer 19

• Compared adolescent WMS patients to Down syndrome patients; found overall scores on IQ and cognitive functioning similar.
  
  • WMS group had trouble with numbers.
  • WMS patients often have cognitive capabilities of a 6 year old, yet still have very mature-sounding speech.
• WMS patients only seem to do well because: 1) other abilities are much worse, making linguistic seem better; 2) can use certain smart-sounding words without full control or understanding; 3) Down syndrome patients tend to underperform

Question 20

event-related potential (ERP) (2)

Answer 20

• Change in electrical voltage (potential) over large numbers of brain neurons, measured with EEG and lined up with the presentation of a relevant stimulus (the event).
• Tell us about the relative timing of linguistic processes, not whereabouts in the brain they occur.

Question 21

N400 (4)

Answer 21

• Processing of meaning (semantic deviants).
• Garden path sentences → brains show more intense activity moving toward a negative voltage and peaking at 400 ms after the odd word was presented.
• A word doesn’t have to be nonsensical in order to trigger the N400, just improbable or unpredictable.
  
  • Also found for uncommon words, even when they’re sensible within their sentence frames, and non-linguistic stimuli that are inconsistent with real-world knowledge (e.g. unfamiliar faces).

Question 22

P600 (4)

Answer 22

• Marker of processing syntactic structure.
• A positive peak at 600 ms when there is a grammar problem in the sentence (e.g. The spoiled child throw the toys on the floor).
• Occurs when a sentence uses an uncommon structure, or if the structure that’s being built strains working memory.
• Also involved in musical “ungrammaticalities,” i.e. most people can tell when a note is out of place even if they’re not a musician.