Split Brain

Front 1

What are the two main myths that arise from split brain studies?

Back 1

1: Humans rely on processing of mostly one hemisphere

2: Two hemisphere work like a spare for one another

ALL BS

3: hemisphere process information with subtle difference in processing styles.

Front 2

How do the right and the left hemisphere communicate ?

Back 2

Using commisural fiber tracts:

corpus callosum

anterior/ posterior commissure

Front 3

What structures in the brain do you see the main lateralization?

Back 3

Only in cortical sturctures>

Front 4

Can you see lateralization of the hyppocampus?

Back 4

Yes it is a cortical structure and not a sub-cortical structure.

Front 5

What are the two therories behind lateralization of function in the human brain?

Back 5

1: Enable speed of processing as transcortical projection and transfer take time.

2: Advantage of having non idnetical forms as each area specialized for a function while basic function is still bilateral.

Front 6

What percentage of left handed people have their language represented in the left hemisphere, right handed?

Back 6

60% LH

96% RH

Front 7

Is there any anatomical discrepency between the right and the left hemisphere concerning language areas?

Back 7

No annatomical study support reliably that anatomical differences are correlated with function ( 65% of RHand but 96% have language on the left ) ( number don<t match)

Front 8

What is the subtele cytoarchitectural differences between the right and left wernicke's area?

Back 8

Spacing of Left Wernicke's area are larger between cells than the right : possibly to accomodate more connections within the left hemisphere. Also subtle cell size differences where larger pyramidal cells in the left hemisphere.

Front 9

How is the connectivity of the corpus callosum generally organised?

Back 9

Usually homotopic areas in corresponding locations in each hemisphere.

Front 10

aproximately how many axons are in the corpus callosum?

Back 10

200 million.

Front 11

What is the difference between homotopic, heterotopic and ipsilateral in terms of connections between corteces?

Back 11

homotopic: corresponding areas

Heterotopic: one area connects to a different area of the other hemispher

Ipsilateral: one area connect to the same side as the initial area.

Front 12

Why would you severe the corpus callosum?

Back 12

to control intractable epilepsy. This contains the seizure and reduces the symptoms.

Front 13

Who was the first researcher to assess the split brain syndrom how did he assess the syndrom?

Back 13

Roger sperry: experiments on cats with severed corpus callosums. Could teach different tasks in each hemisphere.

Front 14

What are the methodolical issues of split brain patients?

Back 14

- only a few accountable patients

- Of these, most show abnormal results in neurological tests

- Language comprehention vary a lot in the right hemisphere

- testing confined to visual stimuli mostly since you have best control.

Front 15

What would be the difference between a RIGHT HANDED patient with no, partial or complete rupture of the corpus callosum if you presented a word in the left visual field?

Back 15

no lesion: will say the word

partial lesion: will have a vague idea of the word and might guess it afterwards

compleet lesion: will say that he/she did not see anything

Front 16

What are the characteristics of a split brain patient?

Back 16

- both hemisphere work independently

- only left hemisphere speaks

Front 17

What one must be carefull with when testing a split brain patient using visual task?

Back 17

be careful about saccades as they will falsify the data tatistoscope can assess this

Front 18

What are the 3 most studied split brain patients?

Back 18

WJ

JW

VP

Front 19

What is the difference between JW and VP's lesion?

Back 19

JW full section of the corpus callosum

VP only partial section ( splenium and anteriorly to it is segregated)

Front 20

What is the grammatical function of language?

Back 20

rule-based system for ordering words

Front 21

What is the lexicon function of language?

Back 21

Mind's dictionnary, words associated with meaning.

Front 22

What phenomenon does both hemisphere show ?

Back 22

The word superiority effect

Front 23

When priming with compatible and incompatible cues concerning words, what is the difference between the right hemisphere and the left hemisphere?

Back 23

Right: will not be affected by priming and hence will not have advantage

Left: willl be primed and will notice advantage in response time.

Front 24

Where is the lexicon function of language lateralized? Grammatical? can this change?

Back 24

Lexicon: both hemisphere though function differently

Grammatical: only on the left hemisphere

Yes can change: demonstrated learning process of grammatical language in right hemisphere. (eg : distinguished between grammatically correct and incorrect sentences)

Front 25

What happens when you expose two different words that could be integrated into one to a split brain patient and ask them to draw the words?

Back 25

You will see segregation between both words (integration willl not occur) eg: fire / arm will draw seperate entities not all together.

Front 26

Where is face processing lateralized? was there an exception in what was seen in the patient studied?

Back 26

Usually lateralized in the right hemisphere but patient VJ had it lateralised to the left hemisphere.

Front 27

in Gazzaniga's experiment of discrimination between the self and non self, what were the results?

Back 27

there was a bias for the self in the left hemisphere

Front 28

normally, is higher ordered processing lateralized between each hemisphere?

Back 28

usually it isn't

Front 29

When doing different versions of the posner cuing test, what was found regarding the difference between the two hemispheres?

Back 29

When directional cuing was done with a normal arrow: no difference but only right hemisphere can be cued with a drawing of facial gaze not the left .

Front 30

What is the interpreter hypothesis? What gazzaniga boldly suggested based on this ?

Back 30

THe hypothesis where the left hemisphere have a tendency to

construct a narrative pf information processes and interprets its meaning.

Gazzaniga suggested that it might be the source of our conscious experiences.

Front 31

in a frequency prediction task what will you see as a difference between the right and the left hemispheres?

Back 31

Left hemisphere: will try and frequency match : try and discern pattern

Right hemisphere: will maximize: always choose the most probable answer.