The nervous system is divided into two parts: Central Nervous System (CNS) : the brain and spinal cord Spinal Cord : nerves that run down the length of the back and transmit most messages between the body and brain Peripheral Nervous System (PNS): nerves branching out from the spinal cord
Neurons Neurons: the long, thin cells of nerve tissue along which messages travel to and from the brain Neurotransmitters: the chemicals released by neurons, which determine the rate at which other neurons fire.
Synapse Synapse: the gap that exists between individual nerve cells
Voluntary and Involuntary Activities Somatic Nervous System (SNS) : refers to the part of the peripheral nervous system that controls voluntary activities. Autonomic Nervous System (ANS) : the part of the peripheral nervous system that controls internal biological functions
Images Computerized Axial Tomography (CAT) : An imaging technique used to study the brain to pinpoint injuries and brain deterioration.
Positron Emission Tomography (PET): An imaging technique used to see which brain areas are being activated while performing tasks
Magnetic resonance imaging (MRI): An imaging technique used to study brain structure and activity
The Endocrine System Endocrine System: a chemical communication system, using hormones, by which messages are sent through the bloodstream Hormones: chemical substances that carry messages through the body in blood
Pituitary Gland: the center of control of the endocrine system that secretes a large number of hormones
Thyroid Gland: produces the hormone thyroxine which stimulates certain chemical reactions that are important for all tissues of the body.
Adrenal Glands: become active when a person is angry or frightened, they release epinephrine and norepinephrine into the bloodstream