Psych 101 Ch 3 Flashcards
Parts of a Neuron- Neuron
Cells in the nervous system that communicate with one another to perform information processing tasks
Cell Body
Coordinates information processing tasks and keeps the cells alive
Dendrites
Receives information from other neurons and relays it to the cell body
Axon
Transmits information to other neurons, muscles, or glands
Myelin Sheath
Insulating layer of fatty material
Nodes of Ranvier
Increase efficiency of signal transmission
Synapse
The junction or region between the axon of one neuron and the dendrites or cell body of another
Types of Neurons- Sensory neurons - to BRAIN
- receives information from external world –> spinal cord –> convey to brain
Motor neurons- to BODY
spinal cord –> to muscles –> induce movement
Interneurons
neurons that connect sensory neurons, motors, or other interneurons
Electric Signaling- Communicating Information Within a Neuron
Resting Potential
When the neuron is at rest, positively charged potassium K+ flow out
cell is negatively charged (-70)
Na+/K+ pump helps maintain and restore resting potential
3Na+ out and 2K+ in
Action Potential
an electric signal that is conducted along the axon to a synapse
occurs only when threshold for stimulation is reached (approx -55 mV)
cell becomes positively charged (+40 millivolts)
Refractory Period
The time following an action potential during which a new action potential cannot be initiated
Chemical Signaling- Synaptic Transmission Between Neurons
An action potential reaches the end of an axon at the terminal button and neurotransmitter is released into the synapses, collected at the receptor of the receiving neuron
Terminal Button
Knoblike structures that branch out from an axon
Neurotransmitter
chemicals that transmit information across the synapses
Receptors
parts of the cell membrane that receive the neurotransmitter and initiate a new electric signal
Neurotransmitters leave the synapses
reuptake- acts like a vacuum
enzyme deactivation- digestion
auto receptors- shuts the gate
Types of Neurotransmitters- Acetylcholine
voluntary motor control, memory, learning
Dopamine
regulates motor behavior, pleasure and emotional arousal
Norepinephrine
influences mood and arousal
Serotonin
regulates sleep, dreaming, mood, aggression, appetite, sexual behavior
Endorphins
chemicals that act within pain and pleasure pathways and emption centers of the brain
How drugs mimic neurotransmitters
many drugs affect the nervous system by increasing, interfering with, or mimicking the manufacture or function of neurotransmitters
The nervous system
an interactive network of neurons that conveys electrochemical information throughout the body
Nerves- bundles of axons and glial cells that support neurons
Central Nervous System
Brain and spinal cord
Peripheral Nervous System
connects the nervous system to the body’s organs and muscles
Somatic + Automatic
Somatic nervous system
a set of nerves that conveys information into and out of the CNS. Communicates with sense organs (eyes) and voluntary muscle
Autonomic nervous system
a set of nerves that carries involuntary and automatic commands that controls blood vessels, body organs, and glands
Divisions of Somatic NS- Sensory nervous system
a set of nerves transmitting sensory input from the body to brain
Motor nervous system
a set of nerves for motor output from brain to body
Division of the Autonomic NS- Sympathetic nervous system
a set of nerves that prepares the body for action in threatening situations
Parasympathetic nervous system
a set of nerves that helps the body return to a normal resting state
Components of the Central Nervous System
The CNS is comprised of the brain and the spinal cord, which communicate and collaborate on a variety of complex tasks
