A nerve cell; the basic building block of the nervous system.
A neuron's bushy, branching extensions that receive messages and conduct impulses toward the body cell. (Left)
The neuron extension that passes messages through its branches to other neurons or to the muscle or glands.
A fatty tissue layer segmentally encasing the axons of some neurons; enables vastly greater transmission as neural impulses hop from one node to the next.
Glial cells (glia)
Cells in the nervous system that support, nourish, and protect neurons; they may also play a role in learning and thinking.
A neural impulse, a brief electrical charge that ravels down a axon.
the level of stimulation required to trigger a neural impulse.
A brief electrical charge that travels down its axon.
The junction between the axon tip of the sending neuron and the dendrite or the cell body of the receiving neuron. The tiny gap at this junction is called the synaptic gap of cleft.
Chemical messengers that cross the synaptic gaps between neurons. When released by the sending neuron, neurotransmitters travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing whether that neuron will generate a neural impulse.
Central Nervous System (CNS)
The brain and spinal cord.
Peripheral nervous system
The sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body.
Sympathetic nervous system
The division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations.
Parasympathetic nervous system
The division of the autonomic nervous system that calms the body, conserving its energy.
The body's "slow" chemical communications system; a set of glands that secrete hormones into the bloodstream.
The base of the brain-stem; control heartbeat and breathing.
A nerve network that ravels through the brain stem and plays an important role in controlling arousal.
The "little brain" at the rear of the brain stem; functions include processing sensory input, coordination movement output and balance, and enabling nonverbal learning and memory.
Neural system ( including the hippcampus, amygdala, and the hypothalamus) located below the cerebral hemisphere; associated with emotions and drives.
Linked to memory
A neural structure lying below (hypo) the thalamus; it directs several maintenance activities ( eating, drinking, body temperature), helps govern the endocrine system via pituitary gland, and is linked to emotion and reward.
Involved in speaking and muscle movements and in making plans and judgments.
Receives sensory input for touch and body position.
Includes areas that receive information from the visual fields.
Included the auditory areas, each receiving information primarily from the opposite ear.
Area at the front of the parietal lobes that registers and processes body touch and movement sensations.
An area at the rear of the frontal lobes that controls voluntary movements.
The large band of neural fibersconnecting the two brain hemispheres and carrying messages between them.