Hello class, and welcome. As your Psychology Professor, I have prepared this
comprehensive study guide for our unit on Biopsychology. This material forms the
biological foundation for understanding how we think, feel, and behave.
Please use this guide to review the core concepts of neuronal communication and brain
structure.
Part I: The Building Blocks – Neuron Structure
The neuron is the fundamental unit of the nervous system. Understanding its anatomy is
crucial to understanding how messages are transmitted throughout the body.
Getty Images
Dendrites: Tree-like extensions at the beginning of a neuron that receive
information (chemical signals) from other neurons and transmit electrical
stimulation to the soma (cell body). Think of them as the "listeners."
Axon: An elongated fiber that extends from the cell body to the terminal endings
and transmits the neural signal. The larger the diameter of the axon, the faster it
transmits information. Think of this as the "talker" or the wire.
, Myelin Sheath: A fatty substance that wraps around the axons of some neurons.
It acts as insulation (like plastic around an electrical wire) to increase the speed
at which electrical impulses travel.
Synapse: The microscopic gap between the axon tip of the sending neuron and
the dendrite or cell body of the receiving neuron. This is where chemical
communication (neurotransmission) actually occurs.
The Action Potential
Neural communication is an electrochemical process. The electrical part is called
the Action Potential.
Definition: A brief electrical charge that travels down an axon.
The All-or-Nothing Principle: A neuron is like a gun; it either fires completely or
it does not fire at all. There is no "weak" or "strong" firing. If the electrical
stimulation exceeds a specific threshold, the neuron fires an action potential of a
fixed strength. If the threshold is not met, nothing happens.
Part II: The Brain – Key Structures
comprehensive study guide for our unit on Biopsychology. This material forms the
biological foundation for understanding how we think, feel, and behave.
Please use this guide to review the core concepts of neuronal communication and brain
structure.
Part I: The Building Blocks – Neuron Structure
The neuron is the fundamental unit of the nervous system. Understanding its anatomy is
crucial to understanding how messages are transmitted throughout the body.
Getty Images
Dendrites: Tree-like extensions at the beginning of a neuron that receive
information (chemical signals) from other neurons and transmit electrical
stimulation to the soma (cell body). Think of them as the "listeners."
Axon: An elongated fiber that extends from the cell body to the terminal endings
and transmits the neural signal. The larger the diameter of the axon, the faster it
transmits information. Think of this as the "talker" or the wire.
, Myelin Sheath: A fatty substance that wraps around the axons of some neurons.
It acts as insulation (like plastic around an electrical wire) to increase the speed
at which electrical impulses travel.
Synapse: The microscopic gap between the axon tip of the sending neuron and
the dendrite or cell body of the receiving neuron. This is where chemical
communication (neurotransmission) actually occurs.
The Action Potential
Neural communication is an electrochemical process. The electrical part is called
the Action Potential.
Definition: A brief electrical charge that travels down an axon.
The All-or-Nothing Principle: A neuron is like a gun; it either fires completely or
it does not fire at all. There is no "weak" or "strong" firing. If the electrical
stimulation exceeds a specific threshold, the neuron fires an action potential of a
fixed strength. If the threshold is not met, nothing happens.
Part II: The Brain – Key Structures
