Lecture 11: Neuroplasticity Flashcards
What is neuroplasticity?
ability of nervous system to respond to intrinsic or extrinsic stimuli by reorganizing its structure, function and connections or learning
What is synaptic plasticity?
the ability of synapses to strengthen or weaken over time, in response to increases or decreases in their activity.
What is Hebbian learning?
neurons that fire together, wire together
What is dendritic spine formation?
where receptors are housed and are designed this way to increase surface area
What is pruning?
this is a healthy process and happens as we age
Does neurogenesis occur in post natal humans?
only occurs in hippocampus and olfactory bulb, you are born with all your neurons
What does happen all the time and can increase as you age?
synpatic formation, creations of new neuron connections not new neurons
main step in neuroplastic changes
What is the process of cell death?
CNS can be damaged by a variety of things which initiates a cascade of celluar changes
- potassium exits, Na, Cl, and Ca enters which allows water to follow Na into cell
- glutamate and aspartate are released causing enzyme disturbances and free radical release
What is CNS shock?
in acute stages there is an altered level of consciousness, hypotonia, motor and sensory changes, cog defecits, decline in function
absence or slowing of neuron firing
What are three zones of CNS damage?
- ischemic zone
- Penumbra
- Diaschisis
What is the ischemic zone?
the area of injury that is not getting blood, major area affected
What is penumbra?
adjacent to ischemic zone, chance of cell death if nothing is done
What is diaschisis?
area that is losing function due to loss of connection/input from ischemic zone
What is medical management of CNS injury?
restore blood flow, tissue in penumbra supplied by collateral circulation
some evidence supports that PT can increase rate and degree of recovery
What is the PT main job dealing with neuroplasticity?
we need to promote the brains ability to reorganize in a functional way
but too early can be harmful
When is the time table for an acute vs chronic injury?
1-6 months is acute, first 1-2 months is a steep learning curve, then slower in months 3-6
after 6 considered chronic- slower but still possible for recovery
What factors influence neuroplasticity?
age, genetics, nature of lesion, co morbidities, previous level of function , environment, TRAINING
What are two methods of measuring neuroplasticity?
diffusion MRI, fMRI
What are the goals of neurorehab?
foster recovery via neuroplasticity
regain lost function
What does neurorehab require from the patient?
active participation in goal directed active movement
must be motivating, challenging, age appropriate, REPETITION
What is use it or lose it principle?
neural circuits not actively engaged in task performance for an extended period of time will break down
What is learned non-use?
is a learning phenomenon whereby movement is suppressed initially due to adverse reactions and failure of any activity attempted with the affected limb, which then results in the suppression of behavior.
What is an example of use it and improve it?
constraint induced movement therapy
What is repetition without repetition?
repetition at first is crucial however if not varied over time then learning will stop and task will become unmotivated
Why is timing important in rehab?
too soon may be harmful but too long of delay may allow for compensatory patterns to develop
What is salience?
emotions modulate the strength of memory consolidation or increased dopamine which strengthens neuroplasticity
What is transference?
ability of plasticity within one set of neural circuits to promote concurrent or subsequent plasticity, can prime adjacent areas for learning
What is interference?
training skills to similar and too close together may block the learning of that skill
What must design interventions consist of?
goal directed, challenging, repetitive, active, variable and linked to function
What is recovery is not possible?
help develop compensatory strategies
