Neurology 0.2 Flashcards
What is neuroplasticity ?
The ability to for the brain to form and recognise synaptic connections and permanently deform
What 3 types of recovery are there following a CNS injury
Unmasking of silent synapses
Diaschisis
Axonal sprouting
What is unmasking of silent synapses
the neurones go to the small place via a different route
What is diaschisis
- > with a neuro- injury there is a reduction in blood supply in areas adjacent to this
What are the two types of axonal sprouting ?
-> neural regenerative
Healing of the nerve itself
->collateral sprouting
reactive axons running parallel to one another - grows old a new branch and goes to the same end point)
Why does the nervous system use mylelination ?
Helps speed up the process, making more connections so the transmission can get there more quickly through different routes
What is motor learning
Building new neuro pathways to learn how to do things ie - walking, tying shoe laces
-> links in with neuroplasticity (learning from experience)
What is shumway cooks 3 capacities
Task
Individual
Environment - cold, warm, what can you see etc
What is the meaning behind shumway-cooks 3 capacities
All 3 combine to facilitate us to learn our movements and complete the task you are trying to do
The more variety you have the more variety you have to learn the skill
What factors influence motor - sensory learning
- repetition
- sensory feedback (TOUCH, SIGHT, HEARING, PROPRIOCEPTION)
- ROM, muscle strength
- psychological - pleasure vs pain
- motivation - drive and desire
- cognitive - decision making
- reasoning - understanding why your doing these things
- concentration and attention - needs to be attentive otherwise will not build up on these pathways
What is the resting state inside the action potential
- 70mv
What is the gate activated by in an action potential
Chemical signals
How does the action potential work
- Sodium enters in where there are less sodiums (inside the membrane) , so there is balance and this changes the charge. HOWEVER If only one (sodium) comes through there is not enough to send a full signal.
- Voltage gates are opened by an electrical signal but need enough charge to reach rather threshold
- If the sodium gate is open and sodiums come through then the charge is increased significantly. This generates enough charge for the Voltage gates to open, allowing more sodium through to balance out.
- The charge inside neuron passes the threshold, which started at minus 70 and now comes to plus 40. This is enough to send the signal, creating a positive voltage inside the nerve.
- If the membrane wall keeps going there is enough charge to activate the sodium gate again (allowing more sodium to come in). This is how an action potential is sent.
- This must then be corrected (can’t stay like this otherwise more signals would not send).
- When a large enough signal has been sent, the potassium signal is then activated and potassium moves towards where there is less as it wants to even this out and maintain balance. This causes a rebound effect, going from positive to negative, past resting state of minus 70 (repolarise= bring negative in).
- There is a period where neurons can’t respond to more messages as it has been negatively charged. This needs to be evened out, by returning to the starting state and going back to equilibrium.
What is a stroke
Life threatening condition where blood to the brain is cut off and looses blood supply for a short period of time - it is eventually resupplied
-> more likely to have one again if had one before
What 2 types of stroke are there
Ischemic (blood clot restricting flow of blood , resulting in cell death)
Haemorrhagic ( weakened blood vessels, bleeds)