CHAPTER 3 NOTES
Please make sure you review the following terms/ concepts from this chapter. This includes not
just knowing the definitions, but also that you feel confident with your knowledge of the terms/
concepts and your ability to apply them critically.
Parts of a neuron and pathway of a signal – Neurons are cells that process and transmit
information across the nervous system. Throughout the brain, neurons receive, integrate, and
generate messages. Parts of a Neuron include:
o Soma – cell body which contains the nucleus
o Axon – projection that transmits signals
o Dendrites – finger-like projections that receive signals from adjacent neurons
o Myelin sheath – insulation tube through which impulses are sent.
o Synapse – where Axon meets Dendrite
Action potential – all or none response – an electrical and chemical process, is the
positively charged impulse that travels down an Axon, this happens by virtue of changes
in the neuron itself. The neuron, like all cells in the body are surrounded by a cell membrane
that is somewhat permeable, letting only certain particles move through it. The fluid on the
inside and outside of the cell contains electrically charged particles called ions. Positively
charged sodium and potassium ions and negatively charged chloride ions are the most
common. Channels within the membrane of the neuron allow the ions to flow between the
inside and outside of the cell. Some of these channels are always open.
Reuptake - The process in the brain of neurons to retrieve chemicals that were not received
by the next neuron
, GENERAL PSYCHOLOGY
CHAPTER 3 NOTES
GENERAL PSYCHOLOGY
CHAPTER 3 NOTES
Sensory neurons – receive incoming sensory information form the sense organs, (eyes, ears,
skin, tongue, and nose). Any sensation you receive—anything you see, hear, touch, taste or
smell activates sensory neurons.
Motor neurons – take commands from the brain and carry them to the muscles in the body.
Each time you move a muscle in your body, intentionally or not, motor neurons are at work.
Mirror neurons - Nerve cells that are active when we observe others performing an action
as well as when we are performing the same action.
Neurotransmitters – diseases they are associated with – Chemicals that transmit
information between neurons.
Acetylcholine, dopamine, serotonin – are responsible for the following functions:
o Acetylcholine – Slows ANS activity, eating drinking, neuromuscular junction;
involved in learning, memory, sleeping and dreaming.
o Dopamine – plays in important role in arousal, mood (especially positive mood);
oversupply correlates with schizophrenia; involuntary muscle control.
o Serotonin – plays role in mood, sleep, eating, temperature regulation; undersupply
correlates with anxiety and depression
CNS – (Central nervous system). The part of the nervous system that comprises the brain
and spinal cord.