UNIT 2: Neuroscience and Behavior Flashcards
- Proposed by Franz Joseph Gall
- Different brain areas accounted for specific character and personality traits
Phrenology
- The body’s information system is built from billions of interconnected cells called neurons.
- It’s what the nervous system is made up of
Neural Communication
- Basic unit of the nervous system; a cell that conducts electrochemical signals
Neuron
- Specialized cells in the nervous system
Nerve cells (neurons)
- Cells that support, nurture, and insulate neurons. remove debris when a neuron dies
- makeup 50% of the brain and spine cells
- play a vital role in learning & memory; help guide neurons to each other, or farther away from them
Glial cells
- Schwann cells
- Oligodendrocytes
- both help myelinate the axon
Types of Glial cells
Life center of the neuron
Cell body
Branching extensions at the cell body. RECEIVES messages from other neurons
Dendrites
- Long extension; transmits messages along
- Passes messages from neuron to neuron
Axon
- Covers the axon to insulate and speed up messages.
- 2-200mph
- Not faster than computers
Myelin Sheath
- Branched endings of an axon that sends messages to other neurons
Terminal (Branches)
- As you experience new things, or learn new things (good or bad) your synapses grow & change
- The brains circuits are continually being modified in response to information, challenges, and changes to environment.
Plasticity
- If it degenerates, then multiple sclerosis (MS) will develop
- Communication to muscles will slow and eventually, you will lose muscle control
What happens if your myelin sheath is damaged
Occurs when positive ions enter the neuron, making it more prone to firing an action potential.
Excitatory Neurotransmitters
occurs when negative ions enter the neuron, making it less prone to firing an action potential.
Inhibitory Neurotransmitters
After a neuron fires an action potential it pauses for a short period to recharge itself to fire again (cell polarizes again to have a slight negative charge).
Refractory Period
pump positive ions out from the inside of the neuron, making them ready for another action potential.
Sodium-Potassium Pumps
When the depolarizing current exceeds the threshold, a neuron will fire. If the depolarizing current fails to exceed the threshold, a neuron will not fire.
All-or-None Response
- Arousal
- Concentration
- Part of “Fight or flight” response
- Undersupply can depress the mood
Norepinephrine
Fight or Flight
Also called adrenaline
High emotion
Increases blood flow
Produced in high-stress situations
Epinephrine (mostly a hormone but CAN act as a neurotransmitter)
- Involved with mood regulation
- Affects mood, hunger, sleep, arousal
- undersupply is linked to depression
Serotonin pathways
- Main inhibitory neurotransmitter
- Calming
- Inhibits movement
-Benzodiazepines (which include tranquilizers such as Valium) and alcohol work on GABA receptor complexes
Gamma-Aminobutyric Acid (GABA)
- Involves loss of neurons in brain that utilize GABA
- Symptoms include jerky involuntary movements and mental deterioration
Huntington’s Disease
- Major excitatory neurotransmitter
- Learning, memory, nervous system development
- Oversupply can overstimulate the brain leading to migraines and seizures
- Some people need to avoid MSG (monosodium glutamate)
Glutamate
- Reduce your perception of pain
- Trigger a positive feeling in the body
Endorphins
- Glutamate
- Aspartate
- Nitric oxide
Excitatory Neurotransmitters
- Glycine
- GABA
- Serotonin
- Dopamine
Inhibitory Neurotransmitters
- Acetylcholine
- Nor Epinephrine
Both Excitatory and Inhibitory neurotransmitters
- Neurotransmitters bind to the receptors of the receiving neuron in a key-lock mechanism.
Lock & Key Mechanism
- Similar to neurotransmitters
and bind to its receptor sites to MIMIC ITS EFFECTS - activate the receptors for certain neurotransmitters and ultimately make the effects of the neurotransmitter stronger
- Heroin, oxycodone. methadone, hydrocodone, opium, and morphine
Agonists
- Bind to receptors, but they BLOCK a neurotransmitter functions
- chemicals that inhibit or oppose the actions of neurotransmitters.
- They sit in receptor sites and block the neurotransmitter from binding with receptors on the dendrites
- Haloperidol - a drug that blocks dopamine and is used to treat schizophrenia symptoms
Antagonists
