hemispheric lateralsation + split brain research

Question 1

lateralisation

Answer 1

-theory specific areas of brain r responsible for specific functions
-eg function of speech rpoduction is associated w/brocas area

Question 2

hemispheric lateralisation

Answer 2

-2 halves of brain are functionally different + certain processes of behaviours are controlled by one hemisphere
-left: controls right side of body
-right: controls left

Question 3

NON lateralised functions

Answer 3

-vision, motor + somatosensory areas r in both hemispheres
-their functions are associated in both hemispheres therefore theyre not lateralised to one hemipshere

Question 4

left

Answer 4

language

Question 5

right

Answer 5

face recognition, drawing ability + spatial tasks

Question 6

AO3-research support

fink et al (1996)

Answer 6

-used PET scans to identify active brain areas during a visual processing task
-ppts were asked to look at both global elements of images + finer details
-when attending to global elements , the r hemisphere was most active + when attending to finer details the l hemisphere was most active

Question 7

AO3

no dominant hemispheres

Answer 7

-most research has suggested the r hemisphere is the synthesiser + l hemisphere is the analyser

Question 8

ao3

no dominant hemipsheres:
nielso et al (2013)

Answer 8

-analysed brain scans from over 1000 ppl aged 2 to 29 yrs old + found ppl used certain hemispheres to attain tasks
-however, there was no evidence for certain tasks + maybe theres no such thing as right or left hemisphere

Question 9

plasticity or lateralisation?

Answer 9

-lateralisation maybe reason. we can perform 2 tasks simultanneously
-some think plasticity could be the reason
- we can do plasticity bc functions can ‘swap filters’

Question 10

sbr

optic chiasm

Answer 10

-part of brain where optic nerves cross
-located at base of brain
-left visual field connect to right hemisphere + vise versa

Question 11

sbr

corpus callosum

Answer 11

-large bundle of nerve fibres located between the hemispheres
-connected to both hemispheres + aloows them to communicate
-if its severed they cant communciate

Question 12

sbr

corpus callostomy

Answer 12

-operation that severes cc
-carried out as an attempt to treat ppl w/ frequent + severe siezures
-as a result their hemispheres no longer able to communicate

Question 13

sbr

sperry 1968
procedure

Answer 13

-11 ppts (9 men 2 woman) who had a severed cc
-image flashed on screen for 1/10th of a sec
-they were asked to do tasks:
-describe: image show to one visual field + asked to describe
-tactile: object placed on one hand + had to describe what they felt
-drawing: ppts presented pic in a visual field+ had to draw what they saw

Question 14

sbr

sperry 1968
conclusions

Answer 14

-People with split brains have two separate visual inner worlds, each with its own train of visual images.

-Split-brain patients have a lack of cross-integration where the second hemisphere does not know what the first hemisphere has been doing.

-Split-brain patients seem to have 2 independent streams of consciousness, each with its own memories, perceptions and impulses ie two minds in one body

Question 15

sperry evaluation

Answer 15

-luck et al (1989) this research team also included gazzaniga
-showed SB ppts were faster at identifying odd one out in an array of similar objects than normal controls
-in ‘normal’ brain, left hemispheres cognitive stratergies are ‘watered down’ by inferior right hemisphere