Neuroanatomy + Physiology Flashcards
Function of microglia?
Like macrophages- immune monitoring and antigen presentation
How can AP conduction be increased?
Increase axon diameter
Myelination
Neurotransmitter at an excitatory synapse and what does it activate?
Glutamate
Na receptors- depolarisation
EPSP- excitatory postsynaptic potential
Neurotransmitter at an inhibitory synapse and what does it activate?
GABA or glycine
Cl receptors- hyperpolarisation
IPSP- inhibitory postsynaptic potential
What is spatial synaptic summation?
Multiple simultaneous inputs
What is temporal synaptic summation?
Repeated inputs building up over time
Adaptation rate of a sensory unit?
Change firing in response to change in intensity, or continuous signal
Conduction velocity of a sensory unit?
Differ in diameter, extent of myelination etc.
What is contrast enhancement?
Differences in activity of adjacent neurons are amplified
What is lateral inhibition?
An active neuron inhibits its neighbours
What is the difference between an ionotropic and metabotropic receptor?
Ionotropic- direct channel that opens/closes- fast transmission
Metabotropic- linked to G-protein- slow transmission
What effect does glutamate have on ionotropic receptors?
Excitatory
depolarisation
What effect does GABA have on ionotropic receptors?
Inhibitory (hyperpolarisation)
What are Type IIb/x fibres also known as?
Fast fatiguing
What are Type IIa fibres also known as?
Fatigue resistant