speech and cortical asymmetry

Question 1

what are gyri?

Answer 1

rounded ridges (surface of the cerebral cortex)

Question 2

what are sulci?

Answer 2

grooves in the cerebral cortex

Question 3

what is found in the precentral gyrus?

Answer 3

primary motor cortex

Question 4

what do focal lesions in the precentral gyrus cause?

Answer 4

cause paralysis or weakness in particular muscle groups

Question 5

what does the central sulcus separate?

Answer 5

parietal and frontal lobe

Question 6

what does the post-central gyrus contain?

Answer 6

primary somatosensory cortex

Question 7

what does the lateral sulcus separate?

Answer 7

separates parietal, frontal lobe from temporal lobe.

Question 8

what is broca’s area?

Answer 8

part of the left frontal lobe, just above the lateral sulcus, which controls spoken speech

Question 9

what did Brodmann do?

Answer 9

• Brodmann noticed subtle differences in neuron type and density in various parts of the cortex and divided them into over 50 areas.

Question 10

what is brodmann area 4?

Answer 10

primary motor cortex

Question 11

what is brodmann areas 1, 2, 3?

Answer 11

somatosensory

Question 12

what is brodmann areas 17, 18, 19?

Answer 12

visual cortex

Question 13

what is brodmann areas 41 and 42?

Answer 13

auditory cortex

Question 14

what is the association cortex?

Answer 14

cerebral cortex outside the primary areas: areas whose function is obscure

Question 15

what controls language vocalisation?

Answer 15

Broca’s area - specialized cortical areas in left hemisphere only just above the lateral sulcus
Insula

Question 16

what is the insula?

Answer 16

hidden region of the cortex in the lateral sulcus which is also active during speech production

Question 17

what is the opercular cortex?

Answer 17

cortex on upper and lower lips of lateral fissure

Question 18

which hemisphere is the opercular cortex thicker on?

Answer 18

the left

Question 19

what is the opercular cortex involved with?

Answer 19

language production

Question 20

what is wernicke’s area?

Answer 20

a cortical area at the proximal end of the superior temporal gyrus in the temporal lobe

Question 21

what is wernicke’s area adjacent to?

Answer 21

primary auditory cortex

Question 22

what does wernicke’s area control?

Answer 22

language perception

Question 23

what are symptoms of Broca’s aphasia?

Answer 23

Halting speech
Repetitive 
Disordered grammar 
Disordered syntax
Disordered work order 
Sense behind words

Question 24

what are symptoms of Wernicke’s aphasia?

Answer 24

Fluent speech
No repetition  
Good syntax
Grammar ok  
Meaningless  
Inappropriate words

Question 25

what is aphasia?

Answer 25

inability to understand or produce speech as a result of brain damage

Question 26

what is expressive aphasia?

Answer 26

use single words (find it difficult to link words in grammatical sentences)

Question 27

what is receptive aphasia?

Answer 27

speak fluently but in an almost meaningless way

Question 28

what joins broca’s and wernicke’s areas?

Answer 28

arcuate fasciculus

Question 29

what is arcuate fasciculus?

Answer 29

bundle of cortico-cortical association fibres

Question 30

what does damage to arcuate fasciculus cause?

Answer 30

conduction aphasia – patients show impaired ability to repeat back heard or written words.
o Patients also have difficulty reading aloud

Question 31

what is speech output characterised by?

Answer 31

word-finding difficulties

Question 32

explain the wernicke-geschwind model

Answer 32

word concepts formed in Wernicke’s –> stored in buffer memory –> Broca’s area via arcuate fasciculus

converted into motor programs –> motor cortex of the mouth, lips and tongue

Question 33

when we speak, how do we hear our own voice?

Answer 33

sound produces patterns of neuronal activity in the auditory cortex which are decoded into perceived words/fractions of words in Wernicke’s area

Question 34

why are our perceived words compared with the output in buffer region?

Answer 34

to see if our physical speech sounds like what we wanted to say

Question 35

what blood vessel supplies Broca’s and Wernicke’s areas?

Answer 35

branches of the middle cerebral artery

Question 36

what do strokes affecting the middle cerebral artery affect?

Answer 36

both the Broca and Wernicke areas: producing global/total aphasia.

Question 37

what scans can be used to show which area of the brain is active during vocalisation/hearing words?

Answer 37

fMRI/PET scans

Question 38

which side of the brain is normally active during listening to speech?

Answer 38

the left

Question 39

how many people have left-hemisphere language specialisation?

Answer 39

70-95%

Question 40

what are right hemisphere regions corresponding to Broca’s and Wernicke’s areas involved with?

Answer 40

tasks requiring non-semantic speech recognition and generation – intonation rhythm and emphasis

non-language communication skills - understanding body language, gesture and emotional content of speech

Question 41

what do lesions of the right hemisphere regions cause?

Answer 41

produce robotic, monotonous speech known as aprosodia

Question 42

what do lesions in area 44 cause?

Answer 42

tend to change patient’s speech to a dull monotone.

Question 43

what do lesions in area 22 cause?

Answer 43

listening errors (can’t tell whether it’s a question, struggles with sarcasm).

Question 44

what do the left prefrontal lobes do?

Answer 44

allows you to focus attention on particular objects/problems, gives you analytical and logical skills (in particular use of language and mathematics)

Question 45

what do the right frontal lobes do?

Answer 45

maintain overall awareness even if you are focusing on something else. Allows you to switch your attention and concentrate on new inputs