Lecture 1: Intro Flashcards
what Is in the central nervous system (CNS)?
Brain
spinal cord
What is in the Peripheral nervous system (PNS)?
cranial nerves and ganglia
spinal nerves and dorsal root ganglia
sympathetic and parasympathetic nerves and gangls
enteric nervous system
is the sensory component ascending or descending?
ascending
what is the pathway of the sensory component?
the PNS sends incoming information up to the brain(CNS) known as ascending/afferent
what is the pathway for the motor component?
the CNS sends signals to muscles and glands known as descending/ efferent
what is afferent
acsending, from PNS to CNS and sensory
what is efferent
descending, from CNS to Muscles and motor
if something doesn’t begin at the cortex what is it known as?
reflexive or autonomic
what is hierarchical organization?
a ranked series; top down effect
*NOT all functions require cerebral control
what is serial processing?
sequential communication between levels
what is parallel processing?
multiple active pathways between each level
what is the output of the PNS DIRECTLY influenced by?
local circuit neurons
descending control from cortex and brainstem
what is the output of the PNS INDIRECTLY influenced by?
basal ganglia and cerebellum
is the PNS upper or lower motor neurons?
lower motor neurons
what is basal ganglia?
inition on intended movement and suppression of unwanted movement
what is the cerebellum?
coordination of ongoing movement
what is the motor cortex?
planning, initiating, and directing voluntary movements
what is the brainstem centers?
rhythmic, stereotyped movements and postural control
what are glial cells? and do they carry signals?
supporting cells of the nervous system, and NO they DO NOT carry signals
what are astrocytes?
most abundant; form blood brain barrier
maintain homeostasis in CNS
what are ependymal cells?
line ventricles
produce CSF
what are microglia cells?
site of trauma
macrophage that eat dead tissue, debris and pathogens
what are oligodendrocytes?
*insulation to multiple
myelinated axons in CNS to improve signal conduction
what are satellite cells?
maintain homeostasis in the PNS
what are Schwann cells?
*one wrapping
myelinated axons in the PNS to improve signal conduction
what is the node of ranvier?
gap in myelin where the signal propagates
what are the two general functions of chemical neurotransmitters ?
rapid communication between neurons
neuomodulation
what is rapid communication of neurons?
excitatory post synaptic potentials and inhibitory post synaptic potentials
what is spatial summation?
emerges from multiple presynaptic neurons to exceed threshold of postsynaptic neuron
what is temporal summation?
a single presynaptic neuron releases many neurotransmitters over time.
what is neuromodulation?
slow signaling
can lead to facilitation or inhibition of subsequent signaling within the neuron
what is glutamate?
most common excitatory neurotransmitter (CNS)
what is GABA?
Most common inhibitory neurotransmitter (CNS)
what is glycine?
inhibitory neurotransmitter (spinal cord, brainstem, retina)
what is acetylcholine?
main transmitter at the neuromuscular junction, parasympathetic ANS, and neuromodulation
what is norepinephrine?
sympathetic ANS and neuromodulation
what is dopamine?
neuromodulation
what is serotonin?
neuromodulation
what is histamine ?
mainly excitatory neuromodulation
where is gray matter located in the CNS?
nucleus
where is gray matter located in the PNS?
ganglia
where is gray matter located in the cortex?
outer layer on gyru
where is gray matter located in the spinal cord?
inner tissue
what is gray matter?
mainly cell body
synaptic communication between neurons (cell-cell communication)
what is white matter?
axons traveling together
mainly myelinated axons
transmission of signals over long distances
where is white mater located in the cortex?
inner tissue
where is white mater located in the spinal cord?
outer layer
what is a tract? (white matter)
axons traveling in a bundle; start and end in the same place
are there synapses in a tract?
NO synapses
what is a pathway (white matter)?
can be made up of multiple tracts
may contain synapses along the way
what are the three functional classes of a neuron?
afferent neuron
efferent neuron
interneuron
what is afferent neuron?
carries information from the periphery toward the brain or spinal cord
ascending (sensory)
what is efferent neuron?
carry information away from the brain or spinal cord
descending (motor; turn on glad/mm)
what are interneurons?
travel short distance; turns on one and sends signal to make sure the another signal doesn’t turn on too
what is brain circuitry?
neurons recieing input from multiple sources at once.
NOT 1:1 RATIO
what is convergence?
many neurons provide input to each neuron
what is divergence?
any one neuron may innervate multiple targets
what is plasticity?
change of strength in synaptic connections
what is short term synaptic plasticity?
fast in the moment change; repetition
what is long term synaptic plasticity?
long term potential and long term depression
long lasting changes
on the cell that received the signal
