Hempispheric Lateralisation and Split Brain Research

Question 1

localisation of brain areas refers to

Answer 1

fact some functions(e.g vision and language) governed by specific areas in brain

Question 2

for some fucntions localised areas appear in

Answer 2

both hemispheres

Question 3

in the case of vision teh visual area is in

Answer 3

left occipital lobe
right occipital lobe

in left and right hemi respectivley

Question 4

In case of langauge how many centres are there

Answer 4

2

Question 5

in case of lang main two centres are only in

Answer 5

the LH

Question 6

Broca’s areas in the

Answer 6

left frontal lobe

Question 7

wernickes areas in the

Answer 7

left temporal lobe

Question 8

language is

Answer 8

lateralised

Question 9

language is lateralised meaning

Answer 9

performed by one hemisphere rather than the other

Question 10

the RH can only produce (language)

Answer 10

rudimentary words and phrases

Question 11

(links to card 12)Eventhough RH can only produce rudimentaryt words and phrases what does it contribute

Answer 11

emotional context to wahts being said

Question 12

(link to card 11) this has led to suggestion LH and RH are what

Answer 12

LH = analyser
RH = synthesiser

Question 13

many functions arent

Answer 13

lateralised

Question 14

many functions arent lateralised , give examples of function that appear in both hemispheres

Answer 14

vision
motor
somatosensory

areas

Question 15

In the case of mototer area teh brain is

Answer 15

cross wired (contralateral wiring )

Question 16

What does motor area in brain being cross wired (contralateral wiring ) mean

Answer 16

RH controls movement on the left side LH controls movement on the right side

Question 17

int he case of vision how is the lateralisation ?

Answer 17

contralateral
ipsilateral

Question 18

what does ipsilateral mean

Answer 18

opposite and same sided

Question 19

in case of vision each eye recieves

Answer 19

light from left visual field

and right visual field

Question 20

The LVF of both eyes connected to

Answer 20

RH

Question 21

The RVF of both eyes connected to

Answer 21

LH

Question 22

In the case of visual laterlisation this allows visual areas to

Answer 22

compare the slightly different perspective from each eye

and

aids depth perception

Question 23

describe the arrangment for auditory input to auditory area

Answer 23

similar to visual

Question 24

how does disparity from the two inputs helps us

Answer 24

locate source of sounds

Question 25

A split brain operation involves

Answer 25

severing connections between RH &LH mainly the corpus callosum

Question 26

what is the purpsoe of split brain reseearh

Answer 26

reduce epilepsy

Question 27

what happens during an epileptic seizure

+ how do you reduce fits

Answer 27

brain xp excesive electrical activity which travels from one hemisphere to another

connections are cut, splitting the brain in two halves

Question 28

split brian research studies how

Answer 28

hemispheres function when cant comm with each other

Question 29

sperry devised system to study how

Answer 29

two seperated hemis deal with e.g speech and vision

Question 30

PROCEDURE who was studied

Answer 30

11 people who had had split brain operation

Question 31

PROCEDURE how were pt studied

Answer 31

using special set up in which
image could be projected to a pt RVF (processed by LH)
and same/ different image could be projected to LVF(processed by RH)

Question 32

PROCEDURE In normal brain what would corpus callosum do

Answer 32

immediatley share info between both hemi giving a complete pic of visual world

Question 33

PROCEDURE corpus callosum function in normal brain v split op pt means presenting image to one hemi of SBPT meant

Answer 33

info cannot be conveyed from that hemi to the other

Question 34

FINDINGS When pic of object shown to pt RVF(linked to LH) what was happened

Answer 34

pt was able to describe waht was seen

but couldnt do this if object was shown to the LVF(RH) they said nothing was there

Question 35

findings - when pic of object shown to pt rvf but then shown to lvf (rh) they said nothin was ther why was this

Answer 35

in the connected brain messages formt eh rh are relayed to teh laguage centres in the LH

but htis isnt possibel in the split brain

Question 36

findigns - WHAT COULD PT NOT DO - ALTHOUGH THEY COULDNT DO THIS WHAT COULD THEY DO

Answer 36

give verbal labels to objects projected tot eh LVF

they could select a matchinng object out of sight using their left hand (linked to RH)

Question 37

FINDINGS - the left hand was able to do hwat

Answer 37

select an object that was most closely associated with an object presented to the to the LVF

e.g ash tray selcted in repsosnes to pic of a cigarette

Question 38

FINDINGS - if a pin up picture was shown to teh LVF what happened

Answer 38

there was an emotional reaction e.g gigle but the pt usually reported seeing nothing or just a flash of light

Question 39

conclusions - what do the observations show

Answer 39

how certain functions are laterlaised in teh brain and support th eview the LH is verbal and the RH is silent but emotional

Question 40

hemispehreic laterilisation eval points

Answer 40

research suppoert

limtation - one brain

Question 41

split brain research eval poitns

Answer 41

research support

methodolgy highly controlled

coutnerpoitn - lack of eco validity

Question 42

eval hemispheric - laterlisation in the connected brian

one strenght is x showing even in x brains the two hemisphere x info x

e.gx et al used x scans to identify which brain areas were x during a x processing task
when pt w x brains were asked to attend to x elemnts of the image such as looking at a pic of a x forest

x of the xx were much more x

when required to focus in on x detials such as x trees the speciic areas of the xx tended to x

this suggest that , at least as far as x processing is concerned, x laterlisation is a feature of the x brain as well as the x brain

Answer 42

one strenght is reseah showing even in connected brains the two hemisphere porcess info diffrently

e.g fink et al used PET scans to idenitfy which brain areas were active during a visual processing task
when pt w conne cted brains were asked to attend to gloabl elemnts of the image such as lookig at a pic of a whole forest

regions of the RH were much more active

when required to focus in on finer detials such as individual trees the speciic areas of the LH tended to dominate

this suggest that , at least as far as visual processing is concerned, hemispheric laterlisation is a feature of the connected brain as well as the split brain

Question 43

limitaiton hemispheric - one brain

one limtiaiton is the idea that the LH as an x and RH as a x may be x

there may be x functions in the RH and LH but research sugeest people dont have a x side of their brain which creates a diff x

x et al analysed brain scans from over x people aged x-29 and did find that people used x hemispheres for x taks which is evidence for x

but there was x evidence of a x side i.e not an xbrian or a xbrain

this suggest the x of left or right x people is x

Answer 43

one limtiaiton is the idea that the LH as an anlyser and RH as a synthesiser may be wrong

there may be diff functions in the RH and LH but research sugeest people dont have a dominant side of their brain which creates a diff perosnality

nielsan et al analysed brain scans from over 1000 people aged 7-29 and did find that people used certian hemispheres for certain taks which is evidence for laterlisation

but there was no evidence of a dominant side i.e not an artists brian or a mathematicians brain

this suggest the notion of left or right brained people is wrong

Question 44

eval split brian research - research support

One strength is that there is research to support the findings of split brain
research in x functioning brains. For example, x and x found that the left
hemisphere was more concerned with x and the x hemisphere is more concerned with x
and x functioning.
x (1986) reinforced this by stating that the right side of the brain is the
x side, whereas the left side of the brain was more x. This supports Sperry’s split-brain
research as it shows that the human brain is x , with each hemisphere having xfunctions.

Answer 44

One strength is that there is research to support the findings of split brain
research in ‘normal’ functioning brains. For example, Rasmussen and Milner (1977) found that the left
hemisphere was more concerned with language and the right hemisphere is more concerned with spatial
and artistic functioning. Ornstein (1986) reinforced this by stating that the right side of the brain is the
creative side, whereas the left side of the brain was more logical. This supports Sperry’s split-brain
research as it shows that the human brain is lateralised, with each hemisphere having different functions.

Question 45

eval split brain research - methodology

A strength of split-brain research is the high levels of x used.
Sperry created a
very carefully x procedure. For example, to stop the natural x for participants to move
their eyes toward the x, the stimulus was only presented for around x milliseconds.
This ensured only the visual field aiming to be x actually saw the x , meaning only x hemisphere
was tested at a x.
This is a strength as it allowed Sperry to carry out a x range of variations of
the x procedure (such as testing x , x and x).
This has x our understanding of
x.

Answer 45

A strength of split-brain research is the high levels of control used.
Sperry created a
very carefully controlled procedure. For example, to stop the natural tendency for participants to move
their eyes toward the stimulus, the stimulus was only presented for around 200 milliseconds.
This ensured only the visual field aiming to be tested actually saw the stimulus, meaning only one hemisphere
was tested at a time.
This is a strength as it allowed Sperry to carry out a wide range of variations on
the original procedure (such as testing faces, words and touch).
This has extended our understanding on
lateralisation.

Question 46

counterpoitn - lacks eco validity

a problem with lateralisation of function and split-brain research is the lack of x
validity. The tasks that the participants were given to do were very x . By Sperry x that
participants did not have enough time to x their eyes (and their visual field), this does not x how
the participants would use their x in x life. It is likely that they would use both x to try and
x for the cut corpus x. Therefore, it is x to make x of lateralisation
based on just the split brain x.

Answer 46

a problem with lateralisation of function and split-brain research is the lack of ecological
validity. The tasks that the participants were given to do were very controlled. By Sperry ensuring that
participants did not have enough time to move their eyes (and their visual field), this does not reflect how
the participants would use their brains in everyday life. It is likely that they would use both eyes to try and
compensate for the cut corpus callosum. Therefore, it is difficult to make generalisations of lateralisation
based on just the split brain research.