Psych 002 - Exam 1
What approach do current scientists take?
- Physiological = relates a behavior to the activity of the brain and other organs - Ontogenetic = All about the structure > Environment, experiences affect brain development along the way - Evolutionary = developments over long periods of time e.g. goosebumps Functional = approaches issues like camouflage of animals
Neurons are unique because:
1. they can send info(neural signal) over long distances in brain and body. 2. They are the only clls that have long cord-like structures = AXONS 3.Only cells that communicate with each other through a synapse
mV
= millivolt = thousandth
Interneurons
AKA intrinsic neurons whose dendrites and axons are comletely contained within a single structure
NT Function of: Histamine
Allergies
A neuron's membrane is SELECTIVELY PERMEABLE. This means that it?
Allows some molecules to pass through it, but blocks others
One thing the All-Or-None Law states is that:
An action potential will always travel at the same speed and strength no matter how strong the stimulation on the neuron's dendrites and soma
We can say that the neural signal has SUCCESSFULLY been transmitted between two neurons when a neurotransmitter:
Binds to its receptor on the postsynaptic membrane resulting in graded potentials
Soma
Body
NT Function of: Glutamate
Brain's main excitatory NT
NT Function of: GABA
Brain's main inhibitory NT
At the axon terminal, the release of neurotransmitters by EXOCYTOSIS is triggered by:
Calcium ions entering the presynaptic membrane during depolarization
4 major components of a neuron
Denrites, Soma/cell body, Axon, Presynaptic terminals
The absolute refractory period for a neuron is the time:
During which a second action potential cannot be triggered, no matter how strong the stimulus
of Glial Cells: Oligodendrocytes
In the CNS, specialized fatty flat glial cells that wrap around the axon of some neurons creating the myelin sheath. If the neuron is damged, these promote cell DEATH
of Glial Cells: Schwann cells
In the PNS, specialized fatty flat cells that wrap around the axon of some neurons creating the myelin Sheath. If the neuron is damaged, these promote regrowth
Vesicles are located________and act to _________.
In the presynaptic terminals, store neurotransmitters
If an EXCITATORY grade potential synapses DIRECTLY ONTO the axon Hillock:
It is POSSIBLE that this SINGLE graded potential can fire an action potential
Efferent neuron
Motor Neuron that refers to carrying away information from a structure
What cells are NOT an example of Glia?
Motor neurons
NT Function of: Acetylcholine
Movement
What 2 glial cells make up the myelin sheath?
Ologendrocytes in the CNS & Schwann cells in the PNS
At a typical synapse, the CHEMICALLY-GATED-CHANNELS that open when a neurotransmitter binds to its receptor are found here:
On the postsynaptic membrane
A function of the myelin sheath is to:
Provide insulation to help keep the action potential moving quickly and without losing speed
Animal research pros & cons & issues
Reasons for studying animals include: The underlying mechanisms of behavior are similar across species and often easier to study in nonhuman species. - We are interested in animals for their own sake. - What we learn about animals sheds light on human evolution. - Some experiments cannot use humans because of legal or ethical reasons.
NT Function of: Dopamine
Reward/reinforcement
Afferent neuron
Sensory Neuron that refers to bringing information into a structure
During the DEPOLARIZATION phase of an action potential, what happens first?
Sodium channels open and and Na+ ions flow into the cell?
NT Function of: Norepinephrine
Stimulant energy
Dualism
The idea that minds are one type of substance and matter is another
Monism
The idea that the universe consists of only one type of being
During the DEPOLARIZATION of an action potential, what electrical change takes place?
The inside of the membrane becomes more POSITIVE compared to the outside
What describes a TYPICAL neuron at REST?
The potassium concentration is lower outside the cell that inside
This active transport system is one necessary way of keeping the concentration of sodium and potassium ions balanced (for polarizationO on either side of the selectively-permeable membrane during RMP:
The sodium-potassium pump
Hyperpolarization
when membrane dramatically becomes lower in mV compared to RMP on axon
Depolarization
when the membrane beomes more positively charged as measure in RMP (means exciting or going up)
Animal research Advantages & Disadvantages
• Advantages of human research: - Can follow instructions. - Can report subjective experiences. - Are less expensive. - Have a human brain. • Advantages of animal research: - Have simpler nervous systems. - Possible to use comparative cross-species approach. - Fewer ethical problems.
Blood brain barrier
- a mechanism that surrounds the brain and blocks most chemicals from entering - The immune system destroys damaged or infected cells throughout the body. - Because neurons in the brain generally do not regenerate, it is vitally important to block incoming viruses, bacteria or other harmful material from entering
Neuron / Glial cell ratio
1 Neuron / 10 Glial cells
Which of the folliwng area(s) of a neuron TYPICALLY receive(s) input from other neurons?
Cell body, Dendrite
of Glial Cells: Astrocytes
Help synchronize the activity of the axon by wrapping around the presynaptic terminal and taking up chemicals released by the axon
At an INHIBITORY SYNAPSE on a dendrite, the binding of the neurotransmitter to its receptor causes:
Hyper-polarization of the postsynaptic membrane
NT Function of: Serotonin
Mood/wellbeing
Substance P.
Pain
The term "Saltatory conduction" refers to the:
Propagation of the electrical neural signal down a long, myelinated axon
Speed of AP
Ranges from 1 meter / second to 100 meters/ second
NT Function of: Enkaphalins
Regulate pain and stress
of Glial Cells: Microglia
Remove waste material and other microorganisms that could prove harmful to the neuron
4 categories of potentials (mV) are:
Resting membrane potential (RMP @ -70mV), Threshold potential (@-65 Mv), Graded potentials including: EPSP and IPSP
A neuron received EPSPs simultaneously at SEVERAL DIFFERENT LOCATIONS on its dendrites and soma. When those EPSPs travel to the axon hillock, they are added together through a process known as :
Spatial summation
NT Function of: Epinephrine
Stimulant confidence & wellbeing
What is true of postsynaptic potentials (PSPs) in general?
They can sum together by spatial and /or temporal summation
What do Biopsychologists do?
They study how the brain and the rest of the nervous system determine what we perceive, feel, think, say, and do.
Where are voltage gated sodium channels not found on a neuron?
Under the myelin sheath
Ions
are either potassium or sodium
Neuron nourishment
needs glucose (a sugar) because the brain uses 20% of the body's oxygen