NSC Exam 4 Study Guide | 100% Correct
Answers | Verified | Latest 2024 Version
What connects the two hemispheres of the brain? - ✔✔cerebral commissures
What is the procedure that separated the two brain hemispheres? - ✔✔commissurotomy
Aphasia - ✔✔brain damage-induced deficit in the ability to produce or comprehend language
What did Broca discover in his research? - ✔✔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? - ✔✔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? - ✔✔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? - ✔✔1)
sodium amytal test
2) the dichotic listening test
3) functional brain imaging
,sodium amytal test - ✔✔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 - ✔✔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? - ✔✔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? - ✔✔corpus callosum
What 3 things did Meyers and Sperry do to restrict visual info to only one eye? - ✔✔1) they cut the
corpus callosum
- this prevents the hemispheres from communicating
2) the cut the optic chiasm
- this prevents signals from the nasal hemiretina from crossing over
3) 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? - ✔✔scotoma
(an area of blindness)
What did Meyers and Sperry find in they experiment with cats? What was their conclusion? - ✔✔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? - ✔✔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? - ✔✔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 - ✔✔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 - ✔✔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? - ✔✔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? - ✔✔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 - ✔✔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? - ✔✔Language
Language sounds, speech, reading, writing, and verbal memory are all primarily lateralized to the ______
hemisphere - ✔✔Left hemisphere
Facial recognition, geometry, recognizing geometric patterns, and mental rotations of shapes are all
primarily lateralized to the _____ hemisphere - ✔✔Right hemisphere
Recognizing emotional facial expressions and expressing emotional content is primarily lateralized to the
_____ hemisphere - ✔✔Right
Words, letters, and arithmetic are lateralized to the ______ hemisphere - ✔✔Left
Which hemisphere plays a greater role in ipsilateral movements? - ✔✔The left hemisphere
Disorders of spatial perception are most likely to be associated with which type of damage? - ✔✔right
hemisphere damage
Answers | Verified | Latest 2024 Version
What connects the two hemispheres of the brain? - ✔✔cerebral commissures
What is the procedure that separated the two brain hemispheres? - ✔✔commissurotomy
Aphasia - ✔✔brain damage-induced deficit in the ability to produce or comprehend language
What did Broca discover in his research? - ✔✔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? - ✔✔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? - ✔✔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? - ✔✔1)
sodium amytal test
2) the dichotic listening test
3) functional brain imaging
,sodium amytal test - ✔✔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 - ✔✔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? - ✔✔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? - ✔✔corpus callosum
What 3 things did Meyers and Sperry do to restrict visual info to only one eye? - ✔✔1) they cut the
corpus callosum
- this prevents the hemispheres from communicating
2) the cut the optic chiasm
- this prevents signals from the nasal hemiretina from crossing over
3) 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? - ✔✔scotoma
(an area of blindness)
What did Meyers and Sperry find in they experiment with cats? What was their conclusion? - ✔✔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? - ✔✔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? - ✔✔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 - ✔✔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 - ✔✔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? - ✔✔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? - ✔✔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 - ✔✔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? - ✔✔Language
Language sounds, speech, reading, writing, and verbal memory are all primarily lateralized to the ______
hemisphere - ✔✔Left hemisphere
Facial recognition, geometry, recognizing geometric patterns, and mental rotations of shapes are all
primarily lateralized to the _____ hemisphere - ✔✔Right hemisphere
Recognizing emotional facial expressions and expressing emotional content is primarily lateralized to the
_____ hemisphere - ✔✔Right
Words, letters, and arithmetic are lateralized to the ______ hemisphere - ✔✔Left
Which hemisphere plays a greater role in ipsilateral movements? - ✔✔The left hemisphere
Disorders of spatial perception are most likely to be associated with which type of damage? - ✔✔right
hemisphere damage
