central nervous system
the brain and spinal cord
peripheral nervous system
nerves that connect the CNS with the rest of the body
the nervous system performs three general functions
(1) sensory function - sense
(2) integrative function - figure it out
(3) motor function - fix it
neuroglia or glial
support, insulate, nourish, and care for delicate neurons
they DO NOT conduct glial cell
neuroglia
Most abundent glial cell
Astrocytes
most important in the transmission of information
neuron
nonmitotic
DO NOT replicate when injured
myelin
fatty material that encases most of the nerve fiber
sensory neuron
carries information from the periphery
motor neuron
makes you move
interneuron
between sensation and motor neurons.
they play a role in thinking, learning, and memory
saltatory conduction
nerve impulse "jumping" from node to node
organism most associated with saltatory conduction
kangaroo
primary source of energy for the brain
glucose
low blood glucose levels result in
hypoglycemia
the grooves that separate the gyri
sulci
dopamine
largely responsible for the activity of the basal nuclei
action potential
a process of polarization, depolarization, and repolarization
polarization
the resting state of a neuron. no nerve impulse is being transmitted.
the cell is quiet
depolarizatin
the neuron is stimulated a change occurs in the cells electrical state
depolarization
cell returning to its resting place. unless the cell repolarizes. it cannot be stimulated again
refractory period
the cells unresponsive period
the phases of the nerve impulse are caused by
the movement of ions, particularly Na+ and K+
the brain is divided into four major areas
the cerebrum, the diencephalon, the brain stem, and the cerebellum
parietal lobe
located behind the central sulcus
primarily concerned with receiving general sensory information from the body
also concerned with reading, speech, and taste
medulla oblongata
often called the vital center because it controls heart rate, bp, and respiratory
always assess the respiratory rate before administering a narcotic, if less than 10 do NOT administer
cerebellum
damage to the cerebellum produces jerky muscle movements, staggering gait, and difficultly maintaining balance or equilibrium
limbic system
functions in emotional states and behavior
reticular formation
concerned with the sleep-wake cycle and consciousness