The study of the nervous system, and the physical and chemical changes involved in
behavior and mental processes.
The nervous system basic and global components.
How scientists learn about the functions of the brain.
The basic unit of information processing in the brain.
o Communicate to the brain, then out of the system.
Soma: Cell body, contains the nucleus.
Dendrites: Receive stimulation from sensory receptors.
Axon: Long extended fiber along which the neural impulse travels.
Terminal Buttons: Bulblike structures that contain neurotransmitters at the end of the
About 100 billion neurons live in the brain.
Major Classes of Neurons
o From sense receptors toward the CNS.
o From sensory to other interneurons or to motor neurons.
o From CNS toward muscles and glands.
o After you do an action, your brain then processes the reaction.
Action Potentials Action Potential:
o The nerve impulse.
o Polarization of cellular fluid within a neuron, which provides the capacity to
produce an action potential.
Properties of the Action Potential
o AllorNone Law
The size of the action is unaffected by increases in the intensity of
stimulation beyond the threshold level.
o Refractory Period
A period during which further stimulation can not cause another action