✓ Hemispheric Lateralisation (AO1)

Question 1

What is the left hemisphere dominant in?

Answer 1

dominant in language and motor speech

Question 2

What is in most people’s left hemisphere?

Answer 2

Broca & Wernicke’s area

Question 3

What is the right hemisphere dominant in?

Answer 3

visual tasks, motor tasks & facial recognition

Question 4

What is the corpus callosum

Answer 4

a thick bundle of nerve fibers that connects the left and right sides of the brain
- allowing the two hemispheres to communicate and share information

Question 5

What is lateralisation?

Answer 5

the tendency for the 2 halves of the brain to not be entirely alike
- each hemisphere has functional specialisations

Question 6

What study is in the hemispheric lateralisation topic?

Answer 6

Sperry’s Split-Brain Research

Question 7

What was the aim of Sperry’s study?

Answer 7

to investigate the extent to which the brain is lateralised by conducting a series of studies involving epileptic patients who experienced a surgical separation of the hemispheres of the brain

Question 8

Method: Who were the participants in Sperry’s study?

Answer 8

11 patients who had epilepsy & had a commissurotomy (severing of the corpus callosum) to reduce seizures

Question 9

Method: Explain the task the ppts were given?

Answer 9

an image or word was presented to one side of the visual field (e.g. left) which was processed by the other side of the brain (e.g. right side)

• as the corpus callosum was cut, info couldn’t be shared from the right side to left side of the brain

Question 10

Method: What were the 4 tasks the ppts were asked to do?

Answer 10

describing what you see
recognition by touch
composite words
matching faces

Question 11

Method: what was involved in describing what you see + what were the results + why?

Answer 11

shown a picture of an object in 1 visual field
+
when a picture of an object was shown to a patient’s RVF they could easily describe what was seen
BUT
if the same object was presented to LVF the patient couldn’t describe what was seen & typically reported that nothing was there
+
language centres are in the left hemisphere

Question 12

Method: what was involved in recognition by touch + what were the results + why?

Answer 12

shown an object & had to select a matching object from a hidden grab bag of different objects
+
altho ppts couldn’t attach verbal labels to objects attached to their LVF they could select a matching object from a grab bag of different objects w their left hand
& the left hand was also able to select an object most closely associated with the object presented to the LVF (e.g. grab an ashtray when shown a cigarette)
altho again they couldn’t verbalise what they were selecting
+
spatial awareness & visual abilities based in the right hemisphere

Question 13

Method: what was involved in composite words + what were the results + why?

Answer 13

2 words presented simultaneously & had to write & say the word they see
+
if 2 words were presented simulataneously, 1 on either side of the VF, the ppt would correctly say the object presented to their RVF but be able to draw the item presented to their LVF
+
left hemisphere (RVF) has language centres & right hemisphere (LVF) is better for visual & motor tasks

Question 14

Method: what was involved in matching faces + what were the results + why?

Answer 14

matching a face from a series of other faces
+
the picture processed by the RH (LVF) was consistently selected correctly, whilst the picture processed by the LH (RVF) was consistently ignored
+
RH is responsible for facial recognition