Central nervous system (CNS) - The portion of the nervous system consisting of the brain and spinal cord.
Spinal cord - A collection of neurons and supportve tissue running from the base of the brain down the center of the back, protected by a column of bones (the spinal column)
Peripheral nervous system (PNS) - All portions of the nervous system outside the brain and spinal cord; it includes sensory and motor nerves.
Somatic nervous system - The subdivision of the peripheral nervous system that connects to sensory receptors ad to skeletal muscles; sometimes called the skeletal nervous system.
Autonomic nervous system - The subdivision of the peripheral nervous system that regulates the internal organs and glands.
Biofeedback - A method for learning to control bodily functions including ones usually thought to be involuntary, by attending to feedback from an instrument that monitors the function and signals changes in it
Sympathetic nervous system - The subdivision of the autonomic nervous system that mobilizes bodily resources and increases the output of energy during emotion and stress.
Parasympathetic nervous system - The subdivision of the autonomic nervous system that operates during relaxed states and that conserves energy.
Neuron - A cell that conducts electrochemical signals; the basic unit of the nervous system; also called a nerve cell.
Glial cells - Nervous system cells that aid the neurons by providing them with nutrients, insulating them, and removing cellular debris when they die.
Dendrites- A neuron's branches that receive information from other neurons and transmit it toward the cell body.
Cell body- The part of the neuron that keeps it alive and determines whether it will fire.
Axon - A neuron's extending fiber that conducts impulses away from the cell body and transmits them to other neurons.
Myelin sheath- a fatty insulation that may surround the axon of a neuron.
Nerves - Bundles of neural fibers (axons and sometimes dendrites) in the peripheral nervous system.
Synapse - The cite where a nerve impulse is transmitted from one nerve cell to another; it includes the axon terminal, the synaptic cleft, and receptor sites in the membrane of the receiving cell.
Neurotransmitter - A chemical substance that is released by a transmitting neuron at the synapse and that alters the activity of a receiving neuron.
Serotonin affects neurons involved in sleep, appetite, sensory perception, temperature regulation, pain suppression, and mood.
Dopamine affects neurons involved in voluntary movement, learning, memory, and emotion.
Acetylcholine affects neurons involved in muscle action, cognitive action, cognitive functioning, memory and emotion.
Hormones - Chemical substances, secreted by organs called glands, that affect the functioning of other organs.
Endocrine glands - Internal organs that produce hormones and release them into the bloodstream.
Melatonin - A hormone, secreted by the pineal gland that is involved in the regulation of...