L8" HEMISPHERIC SPECIALISATION AND LANGUAGE

Question 1

how are the cerebral hemispheres connected?

Answer 1

bundled axons forming the corpus callosum

Question 2

what is the divided visual field?

Answer 2

the visual pathway from the eye to the cerebral cortex via lateral geniculate nucleus of the thalamus

Question 3

describe the visual pathway when looking ahead

Answer 3

• things visible on the left are analysed in the right visual cortex and vice versa
• stimuli presented in the left visual field give rise to signals sent to the right hemisphere

Question 4

describe how the split brain gives evidence for hemispheric specialisation for language

Answer 4

• signals cannot cross between hemispheres
• stimuli processed by the left hemisphere (right of fixation) could be verbally reported but stimuli processed by the right cannot (but can draw)
• right hemisphere unable to generate speech

Question 5

describe how the block design task gives evidence for hemispheric specialisation for visuospatial problem solving

Answer 5

recreating a picture from a set of blocks is easy with the left hand (right hemisphere) but not with right hand

Question 6

describe how a hemisphere is deactivated to give evidence for hemispheric specialisation & lateralisation of language function

Answer 6

• wada test
• sodium amytal injected into carotid arteries
• give patient an object, wake up and ask what it was
• unable to verbally report

Question 7

which hemisphere contains fundamental language components

Answer 7

left

Question 8

where is Broca’s area?

Answer 8

inferior frontal lobe

Question 9

what is affected by Broca’s aphasia?

Answer 9

language production

Question 10

symptoms of Broca’s aphasia

Answer 10

• slow, laboured speech output
• anomia - failure to remember names of things
• paraphasic errors - substituting incorrect speech sounds
• telegraphic speech
• repetition
• agrammatism - difficulty with grammatic utterances eg passive voice