NEURO FINAL EXAM REVIEW!! Flashcards
Define and differentiate between CNS and PNS
CNS, known as the central nervous system, includes the brain and spinal cord area while the PNS, peripheral nervous system, includes all the nerves that are outside the brain and spinal cord.
Divisions of PNS and parts of ANS
The divisions of the PNS are known as the semantic nervous system and the autonomic nervous system
parts of the autonomic nervous system (ANS) are known to divide into the sympathetic and parasympathetic nervous system (fight or flight and rest and digest [SLUDD]). The ANS also deals widely with the peripheral nervous system and is responsible for HR, BP, etc.
Meninges and PAD
Meninges is known for holding three membranes known as PAD (pia mater, arachnoid, and dura mater). The meninges line the skull and encloses the brain and spinal cord.
Function of CSF
Cerebrospinal fluid flows within the brain and helps cushion it from injury while also providing nutrients to the brain.
Functions and anatomy of neuron including soma, dendrite, axon, collaterals, myelin, synapse, synaptic vesicle, neurotransmitter, pre and postsynaptic membranes, nodes of ranvier, axon hillock.
Soma: known as the cell body of the neuron, it is the metabolic base that holds DNA and is responsible for the formation and production of NTs.
dendrite: a treelike receiving zone for neurotransmitters
axon: a single projection off a soma that carries electrical impulses (1 true axon)
collateral axons: a loose wire that communicates with many other cell dendrites
-recurrent collateral axons is a type of collateral axon that communicates with the sending circuit.
myelin: a fatty insulation around the axon in white matter. It works to protect (sometimes speed up) the neurotransmitters traveling down the axon
synapse: a gap between adjacent neurons, there is no touching. It’s spacing is 20nm (billionths) of a meter. This is the site of transfers of neurotransmitters and is where the pre and postsynaptic membranes lie (the end of an axon and new cell dendrites)
synaptic vesicle: the storage bin/bladder for neurotransmitters. Signaled to release NTs by electrical message in the axon.
neurotransmitter: chemical messengers that helps the body function. They are carried from neuron to neuron and their job is the carry this chemical signal to the next target cell (can be nerve, muscle, or a gland).
pre and postsynaptic membranes: The presynaptic terminal is located at the end of the axon and is the place where electrical signals, such as the action potential, is therefore converted into a chemical signal. Postsynaptic terminals, however, are membranes that are less than 50 nm away that also contain receptors.
nodes of ranvier: gaps w/n the myelin for the passage of electrical signal. Different ions enter and exit this area (+ the flow of material).
axon hillock: cone shaped region at the sima and axon.
classes of neurons: unipolar, bipolar, multipolar, and interneuron
unipolar: a neuron that has only one nerve process extending from the cell body (an axon that extends into dendrites)
bipolar: a type of neuron that has 2 extensions (one axon and one dendrite)
multipolar: a type of neuron that processes a single axon and many dendrites and their branches.
interneuron: a neuron that transmits impulses between other neurons and acts as the middle-man between afferent or sensory neurons.
types and functions of glial cells
Astrocyte: star shape and very small, they are the largest populated of all glia and are found in the blood brain barrier. They redirect blood and nutrients
Microglia: housekeeping cells. They clean waste and are the vast majority of glia cells
Schwann: only in the PNS and they work to produce myelin
Oligodendrocytes: only in the CNS and work to produce myelin
Anatomical positions and references
frontal- abduction and adduction
sagittal- flexion and extension
transverse- rotation
anterior- front
posterior- back
medial- inside (midline)
lateral- outside and away from the midline
dorsal- top/back
ventral- bottom/front
White and gray matter, what and why
white matter: underneath the gray matter cortex and is composed of millions of bundles of axons (nerve fibers) that connects the neurons in the brain regions into functional circuits
gray matter: type of tissue in the brain and spinal cord (CNS) which plays a crucial role in allowing all people to function normally day to day. It consists of high concentrations of neuronal bodies and axon terminals and dendrites. We have gray matter because it allows every individual to control their movement, memory, and emotions.
Afferent and efferent
Afferent pathway: known to deal with sensory neurons, this pathway contains nerve fibers that are responsible for bringing sensory information from the outside world into the brain. Involves senses of vision, hearing, smell, taste, touch, pain, and temperature.
Efferent: known to deal with motor neurons, this pathway is known to carry motor information away from the CNS to the muscles and glands of our body to initiate movement and action.
anatomy of the brain
Telencephalon
Diencephalon
Myelencephalon
Metencephalon
Mesencephalon
Telencephalon
L & R hemispheres (thinking part of the brain)
4 lobes (8 total)
cerebrum is another name for this
DIRECTS: motor (voluntary), sensory, learning and memory, language and communication
Brain tissue:
sulci- a groove, crevice, or furrow in medicine
gyri- a ridge on the cerebral cortex
Cerebral cortex:
highest on intellectual function
neocortex (new, babies)
sensory perception, motor, reasoning, though, language
Corpus callosum: band of fibers which connect L & R hem. of the brain
-information highway that allows connectivism
Occipital lobe:
the visual processing center
visual cortex
the primary visual cortex is the Brodmann area
Temporal lobe: involved in auditory perception
-important for the processing of semantics in speech (meaning of..)
-contains hippocampus and plays a key role in the formation of long term memory
-emotion regulation
Frontal lobe:
-dopamine-sensitive neurons in the cerebral cortex
-socially accepted emotions/behaviors
-non task LTMS
-Future executive decision making, problem solving, planning and speech (intelligence)
3 main divisions of the frontal lobe:
-prefrontal cortex
-premotor area
-motor area
Parietal lobe:
-sensory perception for determining spatial sense and navigation
-knowledge of numbers and their relations
-manipulation of objects
Limbic system:
-amygdale: almond-shape
-hippocampus- seahorse
-septum
-basil ganglia
functions: emotion (main), behavior, LTM, olfaction, some movement
Diencephalon
-Thalamus
-Hypothalamus
Thalamus (filter):
-relay and processes info to the cerebral cortex (the highest lvl of intelligence)
-sensation
-spatial sense
-motor signals
-regulations of: consciousness, sleep, alertness
Cerebral cortex: out-most layer of the brain that is responsible for all forms of conscious activity.
Hypothalamus:
-relay station for internal regulation
-direct communication with pituitary gland
-hunger, hormones, thermoregulation, heart rate, sleep rhythms, thirst, pupil control, emotions, bladder, hair growth, memory.
Mesencephalon (midbrain)
-sits between pons and diencephalon
-tectum (roof) consists:
-superior colliculi: relay station for vision
-optic nerve/chiasm
-inferior colliculi: relay station for auditory
tegmentum: substantia nigra (Latin for black surface) and is part of the basil ganglia. Reward, addiction, fine motor movement.
*Inferior=auditory
Parkinson’s disease: unknown death of neurons in substantia nigra. Decreased production of NT dopamine (dopamine is made from one amino acid)
metencephalon
-pons
-cerebellum
pons: life functioning (most protected)
-breathing
-HR and pressure
-BP
-motor control
-sensory analysis
-primitive (simple_ part of brain (similar to gators)
Cerebellum: (little brain and ventral to occipital region)
-stored motor responses
-posture
-coordinated movement
proprioception (6th sense and not reflexive from and to brain)
-attention, language, and emotional function
-regulating fear and pleasure responses
-balance within proprioception
-motor program in cerebellum
-awareness of where we are in space and based on bio-feedback
myelencephalon (medulla)
-medulla oblongata
-last part of spinal cord (before)
-cardiac, respiratory, vomiting, swallowing, reflexes, waste removal
-ANS control: BP and HR
Depolarization
Resting potential:
-static and not excitatory or inhibitory. The environment of the neuron reaches that spots it from sending signals.
-a neuron’s primary composition is protein (that is why it is negative)
Resting potential: -70mV, internal self is negative and not sending a message
Action potential:
-will always be less negative (towards 0) than RP
-must reach the threshold of a specific NT (example, -5 mV) to reach the synapse
-Na+, K+, and Ca+ floods into the neuron through the gated channels at the hillock, closing the channel once the threshold is reached, and repeats going down the axon until it reaches the synapse.
-process takes 1/1000th of a second
-once the threshold reaches the synapse, it stimulates the terminal buton releasing the NT until it reaches the target tissue/ destination. The -5mV is the message.
Inhibition:
-Threshold is a greater negative charge than RP
-example: GABBA’s threshold is -110 mV
-internal negativity of the neuron has to go from -70 mV to -110mV
-this can be done by opening Chloride pumps, bringing in Cl-
-more Cl- in, more negative environment, polarizing the section
-Same thing with refractory periods but CG opens and kicks out Cl- (electrostatic)
-Na+, K+, and Ca+ goes in to repolarize the section
Repolarization:
-getting rid of Na works towards -70 but a neuron does not need to reach resting potential to send another message
-refractory periods:
-absolute refractory period: 1-2 ms
-relative refractory period: 1-5 ms+ (can be different for everyone)
these refractory periods allow the neurons to send a new message and kick Na by Na/K pumps
Na/K pump’s job is to maintain the K in the neuron.
Neurotransmitters and their classes
-endogenous (self-made) chemicals which transmit signals (mssgs) from a neuron to a target cell across a synapse
-60 known NTs
-at least 100 known polypeptides
Classes of NTs:
-amino acid
-monoamine
-soluble gas
-acetylcholine
