Flashcards in CNS Deck (102)
What is the difference between ionotropic and metabotropic neurotransmitter receptors?
Ionotropic: fast, ligand-gated, receptor is present on ion channel
Metabotropic: slower, G-protein coupled, receptor is separate from ion channel, sends G-protein or second messenger to different receptor on ion channel to make it open
What are the 4 parts of the hypothalamus?
Caudal region (mammillary group)
Intermediate region (tuberal group)
Rostral region (chiasmatic group): supraoptic and preoptic regions
What is the function of the caudal region of the hypothalamus?
Relay station for reflexes related to sense of smell
What is the definition of learning?
The acquisition of abilities or knowledge, a change in behaviour which occurs as a consequence of experience, instruction or both.
What is the definition of memory?
The storage of acquired knowledge or abilities for later recall
What are the 2 types of memory?
Declarative: specific facts, events and places often resulting from a single experience
Procedural: skilled motor movements gained through repetitive training/ how to do things
Where are short-term memories formed?
Where are short-term memories consolidated to long-term memory?
Where are long-term memories stored permanently?
Where is accessing and manipulating of long-term memories carried out (through working memory)?
Prefrontal cortex of forebrain
Where are 'how to' procedural memories stored?
Cerebellum and relevant cortical regions
How long does short-term memory last?
Seconds to hours
How long does long-term memory last?
Days to years
What is the definition of a synapse?
Junction between neurones and other neurones, or between neurones and their effector cells
What is the definition of a neurotransmitter?
A chemical released by a synapse that diffuses from the pre-synaptic membrane to the post-synaptic membrane
Packed in vesicles
What are the 3 main types of neurotransmitter?
L-type : slow release, high threshold
T-type : transient (fast) release, low threshold
N-type : neither fast nor slow release
What is summation?
Many subthreshold synaptic inputs arriving simultaneously at a synapse to evoke a postsynaptic action potential
What are local anaesthetics used for?
Which fibres do they target?
Give some examples
Target pain fibres
Examples: Procaine, Lidocaine, Bupivacaine, Mepivacaine
What are opioids used for?
Give some examples
Analgesia and sedation
Morphine, codeine, butorphanol
What is a neuroleptanalgesic?
What is it comprised of?
What are its 3 uses?
A drug which causes sedation and profound analgesia
Neuroleptic and opioid
Pre-med, minor surgical procedures, restraint (large animals)
Why should you always wear gloves and use a rifle when administering etorphine as restraint?
Absorption through cuts or self-injection is fatal
What is the Lewis Triple Response?
A cutaneous response that occurs from firm stroking of the skin which produces an initial red line, followed by a flare around that line, then a wheal.
The Lewis Triple Response occurs due to the release of what chemical?
What are polymodal receptors?
Receptors which pick up different types of pain
Where does decussation occur for:
Motor and touch
Motor and touch: at midbrain
Pain: around the spinal cord segment
Nociception only becomes pain when it reaches what?
Which are the fastest nerve fibres? What speeds do they operate at?
Which are the slowest (and what are their speeds)?
Fastest: A-alpha (72-120 m/s)
Slowest: C-fibres (0.4-2 m/s)
First order neurons synapse in which part of the grey matter of the spinal cord?
Substantia gelatinosa (lamina II)
What is meant by an antidromal impulse?
One in which conduction is opposite to that of the normal (orthodromic) direction