Synaptic integration Flashcards
What are the differences between excitatory and inhibitory synapses ?
Excitatory = glutamatergic
Asymmetric
thick specialised organiser proteins + cytoskeleton
Inhibitory = GABA/Glycine
Symmetric
Thin
What is temporal summation ?
Single presynaptic neurone
Succesive synaptic input that occur before the neurone has had time to fully recover
Sum together to produce overall effect
What is spatial summation?
Multiple presynaptic neurones to one post
What is skeletal muscle force controlled by ?
Rate
Number
Properties
Describe alpha motor neurons
Located in the ventral horn
Occur in pods
Direct innervation of muscle
What is included in one motor unit?
one alpha motor neurone and all its fibres
How many alpha motor neurones innervate each muscle fibre ?
one
What is a smooth sustained contraction ?
Temporal summation
Rapidly repeated stimuli leading to and increased force as muscle doesn’t fully relax between stimuli
What are type one muscle fibres?
Slow twitch
Oxidative
High myoglobin
Darker red
What are type 2 muscle fibres ?
2A=intermediate
2X= fast twitch, glycolytic, low myoglobin, pale
What fibres are associated with gamma efferents ?
Intrafusal fibres
Where are the motor neurones cell bodies located?
Brainstem and spinal cord
How are the motor neurones coordinated ?
By interneurons in local circuits
Governered by descending projections from upper motor neurones in the cerebral cortex + brainstem
