midterm Flashcards
structures/functions of brainstem
pons, medula, midbrain
survival reflexes (BP, HR, CO0
structures and functions of the Diencephalon
thalamus and hypothalamus
homeostasis (thermoregulation), control of the autonomic nervous system, survival behaviours (aggressive, defensive, consummatory, reproduction)
pituitary hormonal regulation
structures and functions of the limbic system
hippocampus and amygdala
judgement, inhibition, memory and attention
basal ganglia functions
regulate motor control - the contraction of opposing muscles
oligodendrocytes
cells that myelinates CNS nerves
1 can do 50 axon segments
cerebellum functions
coordinates voluntary movement, maintain balance, eye movement
cerebral cortex functions
controls sensory and motor activity, language, thought, idea formation, longterm memory storage
schwann cells
myelinate PNS nerves
microglia
the immune (phagocytic) cells of the brain
astrocytes
provides substrates for neurons - clean up after neurons. these cells do not overlap. one of them can unsheath over 100,000 synapses, and can stimulate adjacent astrocytes leading to signal propogation
what is special about astrocytes
they are polarized
describe the physical, chemical, and physiochemical characteristics of the blood brain barrier
physical - no pores/fenestrations - tight junctions. layers of astrocyte and pericyte endfeet provided an added layer of protection
chemical - 5x the amount of mitochondria, which are high in enzymes
physiochemical - lots of plasma protein binding
difference between neurotransmitters and neuromodulators
neurotransmitters are only active for a couple milliseconds, whereas neuromodulators can last multiple seconds
neuromodulators act on receptors distant from their release site, they alter neurotransmission
neurotransmitters act on ionotropic receptors (those that directly modify ion channels)
describe the steps of neurotransmission
- DNA/RNA/Protein synthesis triggers axoplasmic transport
- neurotransmitters are made and stored
- an action potential occurs which depolarizes membranes and opens calcium channels
- neurotransmitters are released and couple to their receptors
- NT removed from synapse either from reuptake or metabolism
major source of NE
locus coeruleus
main roles of NE neurotransmission
- central response to stress
- modulatory role in focus, attention, and performance
- activity in RAS, limbic system, hypothalamus
major source of dopamine
ventral tegmental area - temporal lobe output
major roles of dopamine neurotransmission
extrapyramidal motor system (parkinsons)
limbic system (psychosis and affective disorders)
hypothalamus (reward and pleasure systems)
chemoreceptive trigger zone
major source of serotonin
Raphe nuclei
major source of acetylcholine
nucleus basalis
acetylcholine is majorly involved in this system, causing parkinsins
extrapyramidal motor system
major source of histamine
tuberomammillary nucleus (hypothalamus)
_____ is the major excitatory neurotransmitter
glutamate
true or false - excess glutamate can cause neurodegeneration
true