Systems + Brains & co. Flashcards
Central Nervous System (CNS)
Spinal cord and fluids
Peripheral Nervous System
Sensory nerves that connect to the CNS to relay messages to the brain
Somatic Nervous System
Enables voluntary muscle movement through motor neurons once commands are sent from the brain (motor cortex/cerebellum)
Automatic Nervous System
Largely uncontrollable and functions on autopilot beating the heart, digesting food, and moving organs
Sympathetic Nervous System
Arouses and expends energy (fight or flight)
Parasympathetic Nervous System
Slows your heartbeat, lowers blood sugar, and calms your system after sympathetic makes it all high alert and stuff
Sensory Neurons
relay signals to the brain from sensory receptors (sent to the brain through the CNS)
Neurons
made up of 4-5 main parts: the soma, axons, dendrites, myelin, and synapses.
Soma
the cell body, which contains all the DNA,
and other essential parts for keeping the neuron alive
Axon
Where the message travels through to get to the synapses
Myelin Sheaths
Fat around the axon that protects the neuron
Synapses
Also known as Axon terminal. It is where neurochemicals are released and received by the dendrites
Dendrites
Receives neurochemicals from synapses
Neurotransmitters
When electrical charges travel through the axon, they reach the end and trigger the release of chemicals called neurotransmitters. Chemical particles/messengers. Ex: serotonin, dopamine, endorphins, norepinephrine. Once the neurotransmitters have bound to the receptors, they are sent back to the original axon in a process called reuptake or dissolved
Sodium-Potassium Pumps
Re-separates the Na and K ions in neuron communication. This process is known as action potential, when an electrical Impulse passes through the axons of the communicating neuron
Agonists
chemicals in drugs that can bind and activate the
receptors in the synapses, thus providing the associated feeling. Ex: cocaine, heroine, nicotine
Addiction
Reuptake can be slowed, and these
drugs can overuse and deplete your natural neurotransmitters, leaving you feeling worse afterwards and in need of more drugs
Antagonists
Chemicals that bind and DO NOT activate the receptors—sometimes permanently
Lesions
the destroying of brain cells
Cognitive Revolution
When most of the technology we used to view brains when patients are alive and alert were invented
Electroencephalogram (EEG)
can target the electrical waves in one’s brain, down to a specific stimulus
Computed Tomography (CT) Scans
x-rays that can reveal brain damage
Positron Emission Tomography (PET) Scan
shows brains consumption of chemical fuel—glucose (shows most active regions during activity)
Magnetic Resonance Imaging (MRI)
puts head in strong magnetic field that aligns spinning electrons of brain molecules, then disorients them with a radio wave. When they return to normal, it gives a detail picture of the soft tissues.
Functional MRI
takes MRI scans less than a second apart to track blood flow and reveal activity in areas on the brain
Adrenaline
Hormone. Involved in fight or flight, beneficial in short bursts
Oxycontin
Hormone. Us vs. them hormone, not necessarily the cuddle hormone.
Oxycontin
Hormone. Us vs. them hormone, not necessarily the cuddle hormone.
Cortisol
Stress hormone, like adrenaline helps the body with threats
Testosterone
Hormone involved in sexual arousal and competition (and supposedly not aggression but kinda aggression)
Estrogen(s)
Category of hormones involved in reproduction, sexual desire
Leptin
Involved in turning off hunger
Ghrelin
Involved in turning on hunger
Melatonin
Helps to turn on the sleep process
Acetylcholine (ACh)
Enables muscle action and learning. Lacking = Alzheimer’s
nfluences pleasure, movement, emotion (need more). Lacking = Parkinson’s
Serotonin
Affects mood, hunger, sleep
Lacking = Depression
Norepinephrine
Controls alertness and arousal
Glutamate
Major excitatory neurotransmitter
GABA
Major inhibitory neurotransmitter
Endorphins
Your body’s natural pain killer
Neural Transmission
1) Dendrite receives neurotransmitters
2) Soma decodes transmitters and triggers the cycle
3) Cycle:
a. Resting Potential: A state where there are more positive ions outside the neuron than inside
b. Permeability: the gates open and allow the negative and positive ions to mix
c. When the firing threshold is reached, an Action Potential is sent
d. Neural firing is an “all or none” process
4) Refractory Period: the cell must recharge/ prepare the polarity to fire again
5) Re-uptake: any extra neurotransmitters left in the synapse are reeled back into the axon terminal