Chapter Two Flashcards
Phrenology
German physician Franz Gall’s theory that claimed bumps in the skull could reveal our mental abilities and our character traits
Everything ________ is simultaneously __________.
Psychological, biological
Biological Psychology
Branch of psychology concerned with the links between biology and behavior
Neuron
A nerve cell; the basic building block of the nervous system
Dendrite
Tag bushy, branching extensions of a neuron that receive messages and conduct impulses toward the cell body.
Axon
The extension of a neuron, ending in branching terminal fibers, through which messages pass to other neurons or to muscles or glands
Axons _______, dendrites _______
Speak, listen
Myelin Sheath
A layer of fatty tissue segment ally encasing the fibers of many neurons; enables vastly greater transmission speed of neural impulses as the impulse hops from one node to the next
This disease shows the importance of myelin sheaths as it features a degenerative myelin sheath
Multiple sclerosis
Action potential
A neural impulse; a brief electrical charge that travels down an axon. The action potential is generated by the movement of positively charged atoms in and out of channels in the axon’s membranes
Refractory Period
After a neuron fires an action potential, it pauses for a short period to recharge itself to fire again.
All or None Response
When the depolarize current exceeds the treshold, a neuron will fire. If the depolarizing current fails to exceed the threshold, a neuron will not fire
The intensity of an action potential _________ throughout the length of the axon.
remains the same
Threshold
The level of stimulation required to trigger a neural impulse
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 less than a millionth of an inch wide and is called a synaptic gap or cleft.
Reuptake
Neurotransmitters in the synapse are reabsorbed into the sending neurons through the process of reuptake. This process applies the brakes on neurotransmitter action.
How quickly do neurotransmitter molecules cross the gap and bind to receptor sites?
1/10,000th of a second
Endorphins
Meaning “morphine-within”. Natural, opiate-like neurotransmitters linked to pain control and pleasure.
Acetylcholine (ACh)
One of the best understood neurotransmitters. It enables learning and memory and also triggers muscle contraction
Dopamine
It influences movement, learning, attention and emotion
Serotonin
It affects mood, sleep, hunger, and arousal
Norepinephrine
It helps control alertness and arousal
Gamma-aminobutyric acid (GABA)
It’s a major inhibitory neurotransmitter
Glutamate
A major excitatory neurotransmitter; involved in memory
Malfunctions of Acetylcholine (ACh)
ACh-producing neurons deteriorate with Alzheimer’s disease
Malfunctions of Dopamine
Excess dopamine is linked with schizophrenia and an under supply of dopamine is linked to Parkinson’s disease
Malfunctions of Serotonin
An under supply is linked to depression; antidepressants are meant to raise serotonin levels
Malfunctions of Norepinephrine
Undersupply can depress mood
Malfunctions of GABA
Undersupply is linked to seizures, tremors, and insomnia
Malfunctions of Glutamate
An oversupply can overstimulate the brain, which can lead to migraines and seizures.
Agonists _______ neurotransmitters while antagonists ________ them
Excite, inhibit
Blood-Brain Barrier
Enables the brain to fence out unwanted chemicals circulating in the brain
Terminal Branches of Axons
They form junctions with other cells
Nervous System
The body’s speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems