cerebral cortex Flashcards
What is multiple sclerosis (MS).
Demyelination of neurons in the CNS.
What are the main symptoms of MS. List 3.
Any 3 from:
Blurred vision, fatigue, difficulty walking, numbness or tingling (paraesthesia) in different parts of the body, muscle stiffness and spasms.
What can be used to record the activation of motor axons
Electromyography.
The fast response (twitch) that comes from peripheral nerve stimulation is called what, relating to Electromyography.
The M (motor) wave.
Describe orthodromic and antidromic directionality
Orthodromic - travelling in the normal direction in a nerve fibre
Antidromic - travelling in the opposite direction to that normal in a nerve fibre
What can you use to stimulate cortical motor neurons.
Transcranial magnetic stimulation (TMS).
What does the activation of upper motor neurons lead to.
Stimulation of the entire motor neurone pathway (upper and motor neurons) leading to muscle contraction.
What does the activation of upper motor neurons lead to.
Stimulation of the entire motor neurone pathway (
What is the EMG response called when the upper motor neurons are stimulated.
Motor evoked potential. (MEP)
What is the total motor conduction time (TMCT) referring to.
Time for the action potential to reach the MUSCLE from the BRAIN.
What is the TMCT also known as?
MEP latency.
What is the peripheral motor conduction time referring to.
Time taken for the action potential to reach the MUSCLE from the SPINAL CORD
How do you calculate PMCT.
(M latency + F latency-1) /2
What is central motor conduction time. (CMCT).
TMCT-PMCT
What is the effect of MS on brain stimulation in regards to MEP latency/ TMCT.
-longer than usual MEP latency
-Total motor conduction time - delayed
