AP Psychology Unit 3: Biological Psychology and Neurotransmission Flashcards
(108 cards)
Neuron
A nerve cell; The basic building block of the nervous system
Cell body
The part of a neuron that contains the nucleus; the cell’s life-support center
Dendrites
A neuron’s often bushy, branching extensions that receive and integrate messages, conducting impulses toward the cell body
Axon
The neuron extension that passes messages through its branches to other neurons or to muscles or glands
Myelin Sheath
A fatty tissue layer segmentally encasing the axons of some neurons; enables vastly greater transmission speed as neural impulses hop from one node to the next. It is not fully developed until the age of 25 and is very important to behavior, movement, and thought.
Deterioration of the myelin sheath can lead to multiple sclerosis
Glial Cells
Cells in the nervous system that support, nourish, and protect neurons; they also play a role in learning, thinking, and memory
Action Potential
A neural impulse; A brief electrical charge that travels down an axon
Threshold
The level of stimulation required to trigger a neural impulse (-55 mV)
When excitatory signals outnumber inhibitory signals, the threshold has been reached and an action potential occurs
Refractory Period
In neural processing, a brief resting pause that occurs after a neuron has fired; subsequent action potentials cannot occur until the axon returns to its resting state
All-or-None Response
A neuron’s reaction of either firing (with a full-strength response) or not firing
Synapse
The junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron. The tiny gap at this junction is called the “synaptic gap” or “synaptic cleft”
Neurotransmitters
Chemical messengers that cross the synaptic gaps between neurons. When released by the sending neuron, neurotransmitters travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing whether that neuron will generate a neural impulse
Reuptake
A neurotransmitter’s reabsorption be the sending neuron
Acetylcholine (ACh)
Function: Enables muscle action, learning, and memory
Malfunction: Associated with Alzheimer’s disease or paralysis
Dopamine
Function: Movement, thought process, reward
Malfunction: Oversupply linked to schizophrenia, undersupply linked to Parkinson’s disease
Serotonin
Function: Affects mood, hunger, sleep, and arousal
Malfunction: Undersupply linked to depression and stress. Some drugs that raise serotonin levels are used to treat depression
Norepinephrine
Function: Physical arousal, learning, and memory
Malfunction: Undersupply can depress mood
GABA (gamma-aminobutyric acid)
Function: A major inhibitory neurotransmitter
Malfunction: Undersupply linked to seizures, tremors, anxiety disorders, and insomnia
Glutamate
Function: A major excitatory neurotransmitter; involved in memory
Malfunction: Oversupply can overstimulate the brain, producing migraines or seizures
Endorphins
“morphine within”- natural, opiate-like neurotransmitters linked to pain control and pleasure
Agonist
A molecule that increases a neurotransmitter’s action
Antagonist
A molecule that inhibits or blocks a neurotransmitter’s action
Nervous System
The body’s speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems
Central Nervous System (CNS)
The brain and spinal cord. It is the decision maker, responsible for coordinating incoming sensory messages and outgoing mmotor messages