Lec 5 Neurophysiology Part 4: Neuroplasticity Flashcards
Define Neuroplasticity
Change in neural pathways caused by changes in neural pathways and synapses caused by changes in behavior, environment, and neurological injury
Brain is constantly changing. What is the term “Use it or Lose It” mean?
Resources in the brain are limited, and if necessary, brain will need to optimize for new tasks that are more likely to be used
How does “Use it or Lose It” apply to areas like intellect and personality?
Adapting in a way one reasons, and how their personality changes over the years
How does the brain change? Name (2) main ways
1) Large changes in the inhibition of excitatory pathways
2) Synapses can be weighted differently
What is an example in “changes in inhibition of excitatory pathway”?
Immediately after an injury will result in a decrease in GABA, and this will excite the nervous system
…Spinal Cord Injury
How can a “change in synaptic weights, specifically” be initiated?
Long term Potentiation (LTP)
Long Term Depression (LTD)
What is Long Term Potentiation (LTP)?
Increase in strength of an excitatory synapse
What is Long Term Depression (LTD)?
Decrease in strength of an excitatory synapse
This type of learning is related to Pavlov’s Associated Learning. What is Hebian Learning?
Neurons in the CNS connect to other neurons. Connections that are used more frequently, reinforced, or strengthened will adapt to that pathway.
In Long Term Potentiation, What is commonly studied?
Hippocampal Cells
How does Potentiation work?
Continuous stimulation will allow a stronger response, which is the flow of more memory (ions, Na & Ca) by opening of channels and more stimulation.
Neurogenesis is building of new neurons, but does not contribute much. What is Synaptogenesis?
Existing neurons and axons can branch out to other axons & connect to other cells
Where do large changes of neuroplasticity occur? Provide an example.
Cerebral Cortex
Example: If someone’s needs to have a finger amputated, large changes will show in cerebral cortex.
Topographical map will adjust and show more use of the adjacent fingers
What are some brain imaging studies to provide evidence for Neuroplasticity?
Diffusion Tensor Imaging (DTI)
fMRI
Transcranrial Magnetic Stimulation (TMS)
Neurons of the Central Nervous System can’t recreate itself, but it can…
create new connections with other neurons and
find the best away to adjust and function
What is the most important saying to get out of the Neuroplasticity lecture?
“What fires together, wires together”
**Go Over Notes & Recording for Specifics in Neuroplasticity in Rehabilitation
(59:30)
What are Neuroprosthetics?
Devices that work with the nervous system to restore cognitive, motor, or sensory function
In terms of Cochlear Implants, what are (2) types of hearing loss?
Conductive Hearing Loss: Damage to outer ear, & pressure are not conductive in going in the inner ear
Sensory Hearing Loss:
Damage to Cochlea - hair cells are diminished, and although stimulated nothing will be triggered and no hearing or pitches result
Central Hearing Loss - Neurons in the brain are damaged by the CNS and sound is scrambled
For prosthetic arms, what is Targeted Reinnervation?
Using remaining nerve endings to reroute to new sites in chest muscles to move a prosthetic limb
What are BCI’s?
Decoding a brain’s signals to different muscles in the body. This includes EEG technique, Single Unit Recording
What is Mental Prosthesis (type of BC)?
Identifying on a specific area activate when individual focuses on a specific thing
What is Thought Translation Device (Type of BCI)?
Measuring depolarization of certain cortical neurons
What is Wadsworth BCI?
Analyzing frequency of sensorimotor cortex - area of brain related to movement
What is a Visual Prosthesis?
Small cameras record visual field, when stimulated, can identify what directions are lacking in a blind individual
