Chapter 4 Flashcards
Norepinephrine
Arise from the locus ceruleus in the brain stem.
Influences the level of arousal and attentiveness
Maintains Adequate Blood Pressure
Serotonin
Arise from the brain-stem raphe nuclei and project both upward into the brain and downward into the spinal cord
May have a role in:
- Impulsivity and aggression (low levels of serotonin)
- Depression
- Food intake and weight control
- Alcohol use
Serotonin receptors play a role in the actions of some psychedelic drugs (e.g., LSD)
Dopamine
“Feel good drug”
Plays a role in many differnet functions: Movement, Memory, Attention, Learning
Involved in “fight or flight”
Acts as a reward center
Made by adrenal gland
Endorphins
Chemicals similar to the effects of morphine that are naturally released in the body. Help in reducing stress, relieving pain, and improving mood. Found all throughout the brain, you can get these through sexual activity, exercise, massages, etc.
Glutamate
Found in most regions of the brain
* Excitatory neurotransmitter
* Can bind to 4 different receptors
* Functions: Learning and memory, Energy source for brain cells, Regulate sleep (REM)
Pain levels
* High levels = ALS, MS, stroke, autism,
OCD
* Low levels = exhaustion, insomnia
Acetylcholine
excitatory neurotransmitter- regulated blood pressure and plays a role in memory. insufficiency associated with Alzheimer’s.
GABA
- Also known as gamma-aminobutyric acid.
- Is an inhibitory neurotransmitter»_space; slows down your brain by blocking specific signals in your CNS
- Can help reduce stress, anxiety and improve sleep
- Low levels of GABA»_space; anxiety disorders, schizophrenia, autism, depression
- Examples of drugs: Xanax, Valium
- Recreational form = GHB
Low Levels of GABA
anxiety disorders, schizophrenia, autism, depression
what is a drug example of GABA
Xanax, Valium
fMRI
Functional Magnetic Resonance Imaging
real-time information about changes in brain blood flow as an indiviudal speaks about their mood or performs behavioral/cognitaive tasks
Autonomic nervous system
monitors and controls the body’s internal environment and involuntary functions, like HR & BP
Sympathetic branch
“fight or flight”
EX: norepinephrine (involved in increasing heart rate)
Parasympathetic branch
“rest and digest”
slows heart rate, airways constrict, increases digestion
Somatic nervous system
A part of the body’s PNS is primarily associated with the voluntary control of body movements of the skeletal muscles.
Neurons
primary elements of the nervous system that analyze and transmit information.
Glial cells
A type of cell that provides physical and chemical support to neurons and helps maintain their environment. Located in the central nervous system & peripheral nervous system (sometimes called the glue of the nervous system). There are 3 types:
-microglia
-astrocytes
-oligodendrocytes
PET scan
- A radioactively labeled chemical is injected into the bloodstream, and a computerized scanning device then maps out the relative amounts of the chemical in various brain regions.
- Provides a direct measure of brain activity and an indirect measure of potential toxicity to specific neurons
MRI
Uses a high-power magnet to determine how many hydrogen atoms are in the brain. It is noninvasive and provides a high-resolution image of the brain’s anatomy.
Agonist
mimics the action of neurotransmitters by activating the receptor: ozempic
Antagonist
occupies the receptor and prevents the neurotransmitter from activating it.
Endocannabinoids
Chemical compounds within the endocannabinoid system that are found widely distributed throughout the brain. Endocannabinoids are made in the body, phytocannabinoids are made in the cannabis plant, and synthetic cannabinoids are made in a lab. They produce similar effects as THC, and a drug currently available is Epidolex, which treats seizures.
Homeostasis
maintaining the levels within our bodies in a certain range
Does an MRI provide any information about brain function?
no
Life Cycle of a Neurotransmitter
- precursors are found circulating in the blood supply and the brain
- Uptake- precursors taken up by cells
- Synthesis- precursors synthesized into neurotransmitter by enzymes
- Storage- neurotransmitters stored in synaptic vesicles
- Release- by action potential; neurotransmitters released into synapse
- Binding- neurotransmitters bind with receptors on postsynaptic cell
- Metabolism- after signal is sent, neurotransmitters are removed from the synapse
