NSC EXAM 4 STUDY GUIDE | 100% CORRECT ANSWERS |
VERIFIED | LATEST 2025-2026 VERSION.
What connects the two hemispheres of the brain? - Correct Answer ->>cerebral commissures
What is the procedure that separated the two brain hemispheres? - Correct Answer -
>>commissurotomy
Aphasia - Correct Answer ->>brain damage-induced deficit in the ability to produce or
comprehend language
What did Broca discover in his research? - Correct Answer ->>He discovered that all the aphasic
patients that he saw had damage to their inferior prefrontal cortex. This became known as
"Broca's Area"
What is apraxia? What causes it? - Correct Answer ->>the inability to perform certain movements
when requested our of context (even though they may be physically able to perform them
Almost always caused by left-hemisphere damage
What is the theory of cerebral dominance? What thinking did it lead to? - Correct Answer ->>One
hemisphere (usually the left) assumes a dominant role in controlling complex cognitive and
motor functions
This was supported by the fact that aphasia and apraxia are both caused by damage to the left
hemisphere
It led to people referring to the left hemisphere as the "dominant hemisphere" and the right as
the "minor hemisphere"
What are three tests used to assess the lateralization of the brain besides lesioning the brain? -
Correct Answer ->>1) sodium amytal test
the dichotic listening test
functional brain imaging
,sodium amytal test - Correct Answer ->>injection is given through the carotid artery which
anesthetizes that hemisphere of the brain, allowing the function of the other side to be assessed
Neurosurgeons will use it to see which side of the brain is responsible to language
dichotic listening test - Correct Answer ->>three pairs of spoken digits are played into both ears
simultaneously (e.g. 1,3,6 in the right and 2,4,8 in the left)
They have found that people report hearing more of the digits played in their right ear
What is the difference between dextrals and sinestrals with brain lateralization? How do we
know? -
✔✔Dextrals almost always have language lateralized to the left, and sinestrals usually do, but it
is more variable
We have conformed this from Na amytal tests
Are males' brains more lateralized than females? - Correct Answer ->>The evidence is mixed.
Males have been seen to suffer more consequences from unilateral strokes, but functional brain
imaging has not been able to show increased lateralization
What is the largest cerebral commissure? - Correct Answer ->>corpus callosum
What 3 things did Meyers and Sperry do to restrict visual info to only one eye? - Correct Answer -
>>1) they cut the corpus callosum
- this prevents the hemispheres from communicating
the cut the optic chiasm
this prevents signals from the nasal hemiretina from crossing over
they blindfolded one eye
this blocked both visual fields in that eye
,What did Meyers and Sperry find was produced in cats when the optic chiasm was cut? - Correct
Answer ->>scotoma (an area of blindness)
What did Meyers and Sperry find in they experiment with cats? What was their conclusion? -
Correct Answer ->>They found that, in the control group, the cats were unaffected when the eye
patch was switched to the other eye. However, the cats went back to zero if their optic chiasm
and corpus callosum has been severed
They concluded from this that they corpus callosum transfers info between the two hemispheres.
What is a common treatment for severe seizures? - Correct Answer ->>commissurotomy of the
corpus callosum
If an apple was shown in the left visual field of a split brain patient, how could they identify it?
How could they not identify it? - Correct Answer ->>The patient would be unable to verbally
identify the apple because the right hemisphere is not involved in speech. Therefore, they would
say that they didn't see anything.
However, they could reach under the table and identify a matching object with their left hand,
because it is also controlled by the right hemisphere
What is cross-cuing? Give an example - Correct Answer ->>Cross-cuing is where the two brain
hemispheres can communicate indirectly through an external route.
Ex) if a split brain patient is shown either red, or green in their left visual field, they perform no
better than chance at guessing the color. However, if they pick the wrong color, their right
hemisphere initiates a frown or some other negative response because it knows the verbal
response was incorrect, which prompts the left hemisphere to change its response
What is the helping-hand phenomenon - Correct Answer ->>In some experiments, split-brain
patients are shown two different things in each visual field and told to grab the object that was
shown. The patient tries to grab what was seen by the left hemisphere with the right hand, the
right hemisphere sees it and thinks a mistake is being made, so the left hand reaches out and
tries to stop the other hand.
What is the chimeric figures test? - Correct Answer ->>Split brain patients are shown a picture of
two different peoples' faces combined to make one face. The patient is then asked to describe
what they see, and they claim to
, see a normal, complete face based on the half from the right visual field (left hemisphere).
Basically, both hemispheres see normal, complete pictures of faces, rather than the combination
What is a Z lens? How is it used? - Correct Answer ->>A Z lens is a contact lens that is opaque on
one half, so split brain patients can look at visual stimuli for longer than 0.1 seconds and not have
signals go into the other visual field.
The Z lens can be used to allow patients to assess complex visual stimuli like text, or even
auditory
stimuli. The latter works because a patient may hear an auditory command like "pick up the green
ball" but then they are only able to see the different colors with one visual field due to the Z lens
Can the hemispheres of split-brain patients ever communicate? Give evidence for or against -
Correct Answer ->>Yes. Patients who are shown an emotional image in their left visual field (right
hemisphere) can often verbally respond with the correct emotional response when asked.
What is the most lateralized of all brain functions? - Correct Answer ->>Language
Language sounds, speech, reading, writing, and verbal memory are all primarily lateralized to the
hemisphere - Correct Answer ->>Left hemisphere
Facial recognition, geometry, recognizing geometric patterns, and mental rotations of shapes are
all primarily lateralized to the hemisphere - Correct Answer ->>Right hemisphere
Recognizing emotional facial expressions and expressing emotional content is primarily
lateralized to the
hemisphere - Correct Answer ->>Right
Words, letters, and arithmetic are lateralized to the hemisphere - Correct Answer ->>Left
Which hemisphere plays a greater role in ipsilateral movements? - Correct Answer ->>The left
hemisphere
Disorders of spatial perception are most likely to be associated with which type of damage? -
Correct Answer ->>right hemisphere damage
VERIFIED | LATEST 2025-2026 VERSION.
What connects the two hemispheres of the brain? - Correct Answer ->>cerebral commissures
What is the procedure that separated the two brain hemispheres? - Correct Answer -
>>commissurotomy
Aphasia - Correct Answer ->>brain damage-induced deficit in the ability to produce or
comprehend language
What did Broca discover in his research? - Correct Answer ->>He discovered that all the aphasic
patients that he saw had damage to their inferior prefrontal cortex. This became known as
"Broca's Area"
What is apraxia? What causes it? - Correct Answer ->>the inability to perform certain movements
when requested our of context (even though they may be physically able to perform them
Almost always caused by left-hemisphere damage
What is the theory of cerebral dominance? What thinking did it lead to? - Correct Answer ->>One
hemisphere (usually the left) assumes a dominant role in controlling complex cognitive and
motor functions
This was supported by the fact that aphasia and apraxia are both caused by damage to the left
hemisphere
It led to people referring to the left hemisphere as the "dominant hemisphere" and the right as
the "minor hemisphere"
What are three tests used to assess the lateralization of the brain besides lesioning the brain? -
Correct Answer ->>1) sodium amytal test
the dichotic listening test
functional brain imaging
,sodium amytal test - Correct Answer ->>injection is given through the carotid artery which
anesthetizes that hemisphere of the brain, allowing the function of the other side to be assessed
Neurosurgeons will use it to see which side of the brain is responsible to language
dichotic listening test - Correct Answer ->>three pairs of spoken digits are played into both ears
simultaneously (e.g. 1,3,6 in the right and 2,4,8 in the left)
They have found that people report hearing more of the digits played in their right ear
What is the difference between dextrals and sinestrals with brain lateralization? How do we
know? -
✔✔Dextrals almost always have language lateralized to the left, and sinestrals usually do, but it
is more variable
We have conformed this from Na amytal tests
Are males' brains more lateralized than females? - Correct Answer ->>The evidence is mixed.
Males have been seen to suffer more consequences from unilateral strokes, but functional brain
imaging has not been able to show increased lateralization
What is the largest cerebral commissure? - Correct Answer ->>corpus callosum
What 3 things did Meyers and Sperry do to restrict visual info to only one eye? - Correct Answer -
>>1) they cut the corpus callosum
- this prevents the hemispheres from communicating
the cut the optic chiasm
this prevents signals from the nasal hemiretina from crossing over
they blindfolded one eye
this blocked both visual fields in that eye
,What did Meyers and Sperry find was produced in cats when the optic chiasm was cut? - Correct
Answer ->>scotoma (an area of blindness)
What did Meyers and Sperry find in they experiment with cats? What was their conclusion? -
Correct Answer ->>They found that, in the control group, the cats were unaffected when the eye
patch was switched to the other eye. However, the cats went back to zero if their optic chiasm
and corpus callosum has been severed
They concluded from this that they corpus callosum transfers info between the two hemispheres.
What is a common treatment for severe seizures? - Correct Answer ->>commissurotomy of the
corpus callosum
If an apple was shown in the left visual field of a split brain patient, how could they identify it?
How could they not identify it? - Correct Answer ->>The patient would be unable to verbally
identify the apple because the right hemisphere is not involved in speech. Therefore, they would
say that they didn't see anything.
However, they could reach under the table and identify a matching object with their left hand,
because it is also controlled by the right hemisphere
What is cross-cuing? Give an example - Correct Answer ->>Cross-cuing is where the two brain
hemispheres can communicate indirectly through an external route.
Ex) if a split brain patient is shown either red, or green in their left visual field, they perform no
better than chance at guessing the color. However, if they pick the wrong color, their right
hemisphere initiates a frown or some other negative response because it knows the verbal
response was incorrect, which prompts the left hemisphere to change its response
What is the helping-hand phenomenon - Correct Answer ->>In some experiments, split-brain
patients are shown two different things in each visual field and told to grab the object that was
shown. The patient tries to grab what was seen by the left hemisphere with the right hand, the
right hemisphere sees it and thinks a mistake is being made, so the left hand reaches out and
tries to stop the other hand.
What is the chimeric figures test? - Correct Answer ->>Split brain patients are shown a picture of
two different peoples' faces combined to make one face. The patient is then asked to describe
what they see, and they claim to
, see a normal, complete face based on the half from the right visual field (left hemisphere).
Basically, both hemispheres see normal, complete pictures of faces, rather than the combination
What is a Z lens? How is it used? - Correct Answer ->>A Z lens is a contact lens that is opaque on
one half, so split brain patients can look at visual stimuli for longer than 0.1 seconds and not have
signals go into the other visual field.
The Z lens can be used to allow patients to assess complex visual stimuli like text, or even
auditory
stimuli. The latter works because a patient may hear an auditory command like "pick up the green
ball" but then they are only able to see the different colors with one visual field due to the Z lens
Can the hemispheres of split-brain patients ever communicate? Give evidence for or against -
Correct Answer ->>Yes. Patients who are shown an emotional image in their left visual field (right
hemisphere) can often verbally respond with the correct emotional response when asked.
What is the most lateralized of all brain functions? - Correct Answer ->>Language
Language sounds, speech, reading, writing, and verbal memory are all primarily lateralized to the
hemisphere - Correct Answer ->>Left hemisphere
Facial recognition, geometry, recognizing geometric patterns, and mental rotations of shapes are
all primarily lateralized to the hemisphere - Correct Answer ->>Right hemisphere
Recognizing emotional facial expressions and expressing emotional content is primarily
lateralized to the
hemisphere - Correct Answer ->>Right
Words, letters, and arithmetic are lateralized to the hemisphere - Correct Answer ->>Left
Which hemisphere plays a greater role in ipsilateral movements? - Correct Answer ->>The left
hemisphere
Disorders of spatial perception are most likely to be associated with which type of damage? -
Correct Answer ->>right hemisphere damage
