Language and The Brain

Question 1

Broca’s Area

Answer 1

Posterior section of inferior frontal gyrus (IFG) of dominant hemisphere

Question 2

Wernicke’s Area

Answer 2

Posterior section of superior temporal gyrus (STG) of dominant hemisphere

Question 3

Wernicke-Geschwind Model (1972)

Answer 3

Wernicke’s area recieves input from sensory areas - language comprehension
Wernicke’s area sends signals to Broca’s area and Broca’s area sends them to motor cortex which initiates speech production

Question 4

Hickock-Poeppel Model (2004)

Answer 4

Updated version of Wernicke-Geschwind Model
Dual stream
Ventral stream-maps sounds into meaning
Dorsal stream-maps sounds onto articulatory-based representation

Question 5

Wernicke’s Aphasia (1874)

Answer 5

Comprehension disorder
Caused by damage to left posterior STG
Impairment comprehending language
Produce fluent speech that makes little sense-patient unaware
Single dissociation between Wernicke’s area and language comprehension

Question 6

Broca’s Aphasia (1863)

Answer 6

Production disorder
Caused by damage to left posterior inferior frontal gyrus (IFG)
Slow and non-fluent speech but little problem with comprehension

Question 7

Double Dissociation Between Broca’s and Wernicke’s Areas

Answer 7

Evidence shows that the areas function independently

Question 8

Reading Concepts

Answer 8

Phonemes: basic sound units that may have meaning e.g. pad, pat, bad, bat
Graphemes: phonemes in writing, e.g. ghost has four phonemes ‘gh’ ‘o’ ‘s’ ‘t’
Lexicon: dictionary in the brain

Question 9

Coltheart et al. (1993) Two-Routes

Answer 9

Lexical route: lexicon-sound mapping, direct, faster

Grapheme-phoneme conversion route: phonological recoding, indirect, slower

Question 10

Acquired Dyslexia

Answer 10

Loss of the previous ability to read

Question 11

Surface Dyslexia

Answer 11

Impairment in ability to read irregular words
Comprehension intact
Over-regularisation errors e.g. steak - steek
Homophone confusion e.g. pane - to cause distress
Lexicon-sound mapping problem

Question 12

Phonological Dyslexia

Answer 12

Impairment in ability to read pronouncable pseudo words
Comprehension intact
Difficulty reading non-words
Grapheme-phoneme conversion problem

Question 13

Deep Dyslexia

Answer 13

Similar to phonological plus semantic reading problems

Unable to attach words to their meaning e.g. daughter - sister, kill - hate

Question 14

N400

Answer 14

Component of time locked EEG signals - ERP
Negative-going component, peaks as 400ms for meaning incongruent stimuli but observable between 250-550ms
Viewed as component reflecting meaningfulness
Produced by semantic mismatch/violation/anomoly
More neg for semantically incongruent stimuli in both auditory and visual tasks
Centro-parietal regions
Demonstrated in comparisons between semantically congruent and incongruent stimuli

Question 15

World Knowledge in N400

Answer 15

Hagoort et al. (2004)
The dutch trains are yellow/white/sour and very crowded
Word meaning and world knowledge both accessed for comprehension within 400ms past stimulus
World knowledge in N400

Question 16

Peanut Story (Nieuwland & van Berkum, 2006)

Answer 16

Context overrides typical semantic congruency in sentence comprehension
Contextual info can have rapid and major impact on sentence processing

Question 17

Meaning Comes Before Syntactic

Answer 17

P600: positive going component that peaks at 600ms for syntactically incorrect stimuli - later than N400