| Term 
 | Definition 
 
        | series of interconnected cavities within the cerebral hemispheres and brainstem filled with cerebrospinal fluid |  | 
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        | Term 
 | Definition 
 
        | plasma-like clear fluid circulating in and around the brain and spinal cord |  | 
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        | Term 
 | Definition 
 
        | column of nervous tissue from the brainstem through the vertebrae; responsible for nerve conduction to and from the brain and the body |  | 
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        | Term 
 | Definition 
 
        | three membranes that cover the brain and spinal cord, consisting of the dura matter, pia matter, and arachnoid matter |  | 
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        | Term 
 
        | peripheral nervous system (PNS)
 |  | Definition 
 
        | nerves that branch from the central nervous system including nerves of the brain (cranial nerves) and spinal cord (spinal nerves) |  | 
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        | Term 
 | Definition 
 
        | 12 pairs of nerves arising from the brain |  | 
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        | Term 
 | Definition 
 
        | 31 pairs of nerves arising from the spinal cord |  | 
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        | Term 
 | Definition 
 
        | nerves that conduct impulses from body parts and carry sensory information to the brain; also called afferent nerves |  | 
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        | Term 
 | Definition 
 
        | nerves that conduct motor impulses to smooth muscle, cardiac muscle, and various glands |  | 
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        | Term 
 
        | autonomic nervous system (ANS)
 |  | Definition 
 
        | nerves that carry involuntary impulses to smooth muscle, cardiac muscle, and various glands |  | 
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        | Term 
 | Definition 
 
        | control center for the autonomic nervous system located below the thalamus (diencephalon) |  | 
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        | Term 
 
        | sympathetic nervous system |  | Definition 
 
        | division of the autonomic nervous system that is concerned primarily with preparing the body in stressful or emergency situations |  | 
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        | Term 
 
        | parasympathetic nervous system |  | Definition 
 
        | division of the autonomic nervous system that is most active in ordinary conditions; it counterbalances the effects of the sympathetic system by restoring the body to a restful state after a stressful experience |  | 
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        | Term 
 | Definition 
 
        | impairment because of localized brain injury that affects the understanding, retrieving, and formulating of meaningful and sequential elements of language, as demonstrated by an inability to use or comprehend words; occurs as a result of stroke, head trauma, or disease |  | 
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