OCCTH 585- Neuro Exam Questions and Answers
(Graded A)
How do we know the brain is capable of being changed? - Answer1. Skill acquisition:
our brain layout must change to allow for the acquisition of new capabilities
2. nervous system develops as you grow
3. aging: after age 21 we start to lose neurons so the neurons left over will adapt to pick
up the slack
4. Nervous system changes following injury or disease
5. Recovery: the brain will go through neuroplasticity to optimize what it has left
/.The main communicating cells of the nervous system are: - Answerneurons
/.In what ways does neuroplasticity occur? - Answer1. change in the properties of
neurotransmission via a change in PSP size or shape and/or a change in the transmitter
released
2. changing the cell properties by changing the size/shape of the cell, it's electrical
properties/resistance and/or leakiness of the membrane
3. structural changes in the cell
/.Describe the process of unmasking - Answerthe process of exposing present
synapses that were previously silent
/.You're working on reducing a recent lower limb amputee's phantom limb pain when
they ask you the reason for why they still feel sensation in a limb that is no longer there.
What phenomenon is the likely cause and how would you explain it? - AnswerThey are
experiencing unmasking. I would inform them that while they are no longer getting
sensory input from that limb, there are neurons in that cortical area of the brain that
have now been exposed. These neurons receive inputs from other areas of the body
which result in the the sensation felt by the amputated limb.
/.Describe the process of dendritic pruning - AnswerIf a neuron loses inputs from a cell
following disease or injury and the vacant spots are not filled, the dendrites will begin to
retract causing changes to the cell's shape/size and thus its behaviour
/.compare and contrast unmasking vs dendritic pruning - Answerunmasking occurs
immediately and results in functional changes to the cells that influence its behaviour
dendritie pruning occurs over time and results in a loss of SA, brain mass, and changes
to the shape/size of the cell which leads to changes in behaviour
/.Simply put, collateral sprouting is... - Answergrowth of new synapses onto a cell
, /.When a neuron has vacant real estate, this space will emit a chemical signal and
nearby cells will begin to form synapses towards those vacancies, what is this process
called? - Answercollateral sprouting
/.Provide characteristics of collateral sprouting - Answer- requires time to grow new
tissue
- may or may not fill vacant space in the nervous sytem
- is activity dependent (more active neurons= more collaterals)
- produces functional changes as they provide more inputs leading to domination of a
cell
/.Neurogenesis - Answergrowth of new neurons
/.T/F: Adults can't generate new neurons in the central nervous system. Explain -
AnswerFalse. Adults can generate new neurons in very limited anatomical regions such
as the hippocampus, lateral ventricle, and cortex
/.How are neurons involved in learning and memory - Answerwe change the structure of
synapses to retain memory and go through new learning when we want to forget
memories
- cells only live for a couple months before they get turned over
/.Is it possible to use neurogenesis for long term neurological recovery? - AnswerNot
yet. Neurogenesis happens in a fixed pattern and cells go through a lifetime of learning
and experience to get them to where they are. It would be difficult to take a generic cell
and plop it into a system that requires it to do a specific task. May also cause chaos to
the system
/.Why are we unable to grow collaterals across a great distance? - Answerthe farther
from a target you get, the more diffused and diluted the chemical signals get making it
unnoticeable after a certain point. There are also various barriers and obstacles that get
in the way.
/.T/F a neuron must be active for collateral sprouting to occur. Defend your answer -
AnswerTrue. The cell must be able to take up the chemical being released by the
vacant space and it will only achieve this when an AP occurs.
/.(blank) are released from (blank) to stabilize the position of a synapse -
Answerneurotrophins; dendritic spine
/.How does a dendritic spine that finds a synapse closer to the cell body behave? -
AnswerSince it's closer to the cell body it will ahve a stronger E/IPSP and reduced
likelihood of the current leaking out
(Graded A)
How do we know the brain is capable of being changed? - Answer1. Skill acquisition:
our brain layout must change to allow for the acquisition of new capabilities
2. nervous system develops as you grow
3. aging: after age 21 we start to lose neurons so the neurons left over will adapt to pick
up the slack
4. Nervous system changes following injury or disease
5. Recovery: the brain will go through neuroplasticity to optimize what it has left
/.The main communicating cells of the nervous system are: - Answerneurons
/.In what ways does neuroplasticity occur? - Answer1. change in the properties of
neurotransmission via a change in PSP size or shape and/or a change in the transmitter
released
2. changing the cell properties by changing the size/shape of the cell, it's electrical
properties/resistance and/or leakiness of the membrane
3. structural changes in the cell
/.Describe the process of unmasking - Answerthe process of exposing present
synapses that were previously silent
/.You're working on reducing a recent lower limb amputee's phantom limb pain when
they ask you the reason for why they still feel sensation in a limb that is no longer there.
What phenomenon is the likely cause and how would you explain it? - AnswerThey are
experiencing unmasking. I would inform them that while they are no longer getting
sensory input from that limb, there are neurons in that cortical area of the brain that
have now been exposed. These neurons receive inputs from other areas of the body
which result in the the sensation felt by the amputated limb.
/.Describe the process of dendritic pruning - AnswerIf a neuron loses inputs from a cell
following disease or injury and the vacant spots are not filled, the dendrites will begin to
retract causing changes to the cell's shape/size and thus its behaviour
/.compare and contrast unmasking vs dendritic pruning - Answerunmasking occurs
immediately and results in functional changes to the cells that influence its behaviour
dendritie pruning occurs over time and results in a loss of SA, brain mass, and changes
to the shape/size of the cell which leads to changes in behaviour
/.Simply put, collateral sprouting is... - Answergrowth of new synapses onto a cell
, /.When a neuron has vacant real estate, this space will emit a chemical signal and
nearby cells will begin to form synapses towards those vacancies, what is this process
called? - Answercollateral sprouting
/.Provide characteristics of collateral sprouting - Answer- requires time to grow new
tissue
- may or may not fill vacant space in the nervous sytem
- is activity dependent (more active neurons= more collaterals)
- produces functional changes as they provide more inputs leading to domination of a
cell
/.Neurogenesis - Answergrowth of new neurons
/.T/F: Adults can't generate new neurons in the central nervous system. Explain -
AnswerFalse. Adults can generate new neurons in very limited anatomical regions such
as the hippocampus, lateral ventricle, and cortex
/.How are neurons involved in learning and memory - Answerwe change the structure of
synapses to retain memory and go through new learning when we want to forget
memories
- cells only live for a couple months before they get turned over
/.Is it possible to use neurogenesis for long term neurological recovery? - AnswerNot
yet. Neurogenesis happens in a fixed pattern and cells go through a lifetime of learning
and experience to get them to where they are. It would be difficult to take a generic cell
and plop it into a system that requires it to do a specific task. May also cause chaos to
the system
/.Why are we unable to grow collaterals across a great distance? - Answerthe farther
from a target you get, the more diffused and diluted the chemical signals get making it
unnoticeable after a certain point. There are also various barriers and obstacles that get
in the way.
/.T/F a neuron must be active for collateral sprouting to occur. Defend your answer -
AnswerTrue. The cell must be able to take up the chemical being released by the
vacant space and it will only achieve this when an AP occurs.
/.(blank) are released from (blank) to stabilize the position of a synapse -
Answerneurotrophins; dendritic spine
/.How does a dendritic spine that finds a synapse closer to the cell body behave? -
AnswerSince it's closer to the cell body it will ahve a stronger E/IPSP and reduced
likelihood of the current leaking out
