Neurophysiology Flashcards
Most synapses are tripartite. What does this mean?
Most synapses consist of 3 components.
What are the 3 components of a synapse?
Presynaptic terminal.
Postsynaptic terminal.
Glial cell.
How do astrocytes modulate synaptic behaviour?
The NTs released from neurons also bind to receptors on the adjacent astrocyte process, activating signalling pathways in the astrocytes.
What is the structure of a sensory neuron?
Pseudo-unipolar cell body.
Branched dendrite myelinated by Schwann cells.
Central projection that branches in the spinal cord.
Surround by a satellite cell.
Few synapses.
What is the role of the central projection of a sensory neuron?
Innervates motor neurons directly and indirectly via interneurons.
What is the structure of an interneuron?
Short unipolar axon.
Short dendrites.
Limited number of synapses.
Which types of neurons provide input to lower motor neurons?
Sensory neurons either directly or via interneurons.
Descending upper motor neurons.
Where do inputs occur on a motor neuron?
Largely on dendrites in a large dendritic field.
Also on the cell body and axon.
What type of receptor is an NMDAR?
Ionotropic glutamate receptor.
What type of receptor is an AMPAR?
Ionotropic glutamate receptor.
What type of receptor is an MGluR?
Metabotropic G-protein coupled glutamate receptor.
What type of receptor is GABAa?
Ionotropic receptor.
What type of receptor is GABAb?
Metabotropic receptor.
What is the role of NMDAR and AMPAR?
Mediate fast synaptic transmission.
What is the role of MGluR?
Mediate slow neuromodulatory effects.
What is the role of GABAa?
Mediate fast inhibition.
What is the role of GABAb?
Mediate slow synaptic inhibition.
What are some antagonists of AMPAR?
CNQX.
NBQX.
What are some antagonists of NMDAR?
AP5.
AP-7.
What are some channel blockers of NMDAR?
Magnesium ions.
Phencyclidine.
Ketamine.
MK801.
What does psychophysics mean?
The physical characteristics of a stimulus related to mental sensation.
What does sensory physiology mean?
The mapping of how stimuli are transduced by sensory receptors and processed in the brain.
What is the neuronal firing pattern of a slowly adapting receptor?
Starts at the point of the stimulus and then gradually slows down.
What is the neuronal firing pattern of a rapidly adapting receptor?
Starts at the point of the stimulus and then adapts rapidly and stops firing.
What do slowly adapting receptors signal?
A stimulus is constant.
What do rapidly adapting receptors signal?
A stimulus has changed.
What are relays?
Successive levels in the neuronal network.
What are the two roles of relays?
- Allow integration of information across spatial and temporal domains.
- Allow top-down selection of or attention to stimuli through neuromodulation.
What is an example of top-down neuromodulation?
When listening to a piece of music, we are able to isolate the melody of the violin from the melody of the piano.
