Module 5 - Nervous System

Central nervous system (CNS)

Includes brain and spinal cord

Peripheral nervous system (PNS)

Includes cranial nerves and spinal nerves

Meninges

Three connective tissue membranes that cover the brain and cover, protect, and nourish the spinal cord

Number of cranial nerves

12 pairs

Origin of cranial nerves

Brainstem

Where the brainstem carries impulses between

Head and neck

Number of spinal nerves

31 pairs

Where spinal nerves carry messages between

Spinal cord, chest, abdomen, and extremities

Neurons

Basic structural and functional units of nervous system, which interconnect to form complicated networks called nerves

Neuroglia

Supportive and protective units of nervous system which do not transmit electrical impulses

Phagocytic cells

Small glial cells that protect CNS from disease by engulfing and digesting invading microbes

Cerebr/o

Cerebrum

Encephal/o

Brain

Gli/o

Glue; neurological tissue

menin/go; meningi/o

meninges (membrane covering brain and spinal cord)

myel/o

spinal cord

neur/o

nerve

-paresis

partial paralysis

-phasia

speech

-plegia

paralysis

-lepsy

seizure

Paraplegia effects

Loss of motor and sensory function in legs and trunk

Quadriplegia effects

Loss of bowel, bladder, and sexual function, as well as motor and sensory function in all four limbs

Complete spinal cord injury

No feeling or function beneath the injury

Incomplete spinal cord injury

Some feeling and function remaining beneath the injury

Spina Bifida

Developmental defects of the first trimester, characterized by incomplete closure of the bones encasing the spinal cord; most common and least severe spinal cord defect

Meningocele

Spinal bifida classification where sac only contains meninges and cerebrospinal fluid (CSF)

Meningomyelocele

Spina bifida classification where sac contains meninges, CSF, and a portion of the spinal cord

Stroke

Insufficient supply of oxygenated blood to brain due to a clot or ruptured blood vessel (hemorrhage) which causes brain tissue to die (ischemia)

Ischemic stroke

Stroke where the blood supply to brain is blocked or significantly slowed, caused by a thrombus (clot) when an occlusion builds up in an artery

Hemorrhagic stroke

Stroke caused by a ruptured cerebral vessel that allows blood to escape into brain tissue and results in an intracerebral hemorrhage or subarachnoid hemorrhage

Intracerebral hemorrhage

Hemorrhage which occurs in the deeper tissues of the brain, usually caused by uncontrolled hypertension

Subarachnoid hemorrhage

Hemorrhage which occurs on the surface of the brain, commonly caused by a ruptured cerebral aneurysm; very serious and requires surgery

Transient ischemic attack (TIA)

Mild, stroke-like symptoms that usually resolve in 24 hours which commonly precede strokes

Dysphasia

Language disorder that affects the ability to produce and understand spoken language.

Hemiparesis

One-sided muscle weakness

Dysphagia

Difficulty swallowing

Alzheimer disease

Deficiency of function of neurotransmitters due to neuritic plaques and neurofibrillary tangles instead of normal, orderly arrangements in the brain

Alzheimer disease stage 1

Increasing forgetfulness

Alzheimer disease stage 2

Progressive cognitive deterioration causes difficulty doing simple calculations or answering questions

Alzheimer disease stage 3

Ability to recognize others is lost, complete dependency

Increased levels of what in the brain allow better functioning in the case of Alzheimer disease?

Acetylcholine

Cognition

the ability to think; includes attention, memory, learning, reasoning, problem solving, and decision making

craniotomy

incision of the skull to gain access to the brain during neurological procedures

epilepsy

disorder affecting the CNS that is characterized by recurrent seizures

hydrocephalus

cranial enlargement caused by accumulation of fluid within the ventricles of the brain

neuritic plaques

accumulations of amyloid protein found in the gray matter of the brain that are frequently characteristic of Alzheimer disease

sciatica

severe pain in the leg along the course of the sciatic nerve, which travels from the hip to the foot

Lumbar puncture

Needle puncture of spinal cavity to withdraw a sample of cerebrospinal fluid; used for biochemical, microbiological, and cytological laboratory analysis and can introduce agents into spinal canal (anesthetics, radiopaque
substances)

Electroencephalography (EEG)

Recording and analysis of electrical activity of the brain; Helpful in studying epilepsy and convulsive disorders and locating lesions in the cerebrum.

Electromyography (EMG)

Recording and analysis of electrical activity of selected muscle groups while at rest and during voluntary contraction. Test determines whether muscle weakness is caused by a muscular disease or nerve damage and aids in diagnosis of neuromuscular disorders.

Positron emission tomography (PET)

Imaging procedure that records metabolic activity through use of a tracer that emits positively charged molecules. Identifies areas of abnormal activity that occur in schizophrenia, tumors, epilepsy, stroke, and Alzheimer disease.

Computed tomography (CT) scan

Use of a computer to generate three-dimensional images; especially effective in diagnosing disorders of the brain and spinal cord. Used to visualize tumors, abscesses, hemorrhage, and trauma.

cerebrospinal

pertaining to the cerebrum and spine

neurotripsy

crushing a nerve

poliomyelitis

inflammation of gray matter of spinal cord

quadriplegia

paralysis of four (limbs)

neuroblastoma

tumor of nerve, embryonic cell

hydrocephalus

condition of water in the head

neurolysis

separation, destruction, or loosening of a nerve

Thalamotomy

Partial destruction of the thalamus portion of the brain; used as a treatment for psychosis and intractable pain.

Trephination

Excision of a circular disk of bone using a specialized saw called a trephine, which reveals brain tissue for neurosurgery. Used to relieve ICP.

Trephine

Specialized saw for excising a circular disk of bone

Anticonvulsants/antiepileptics

Drugs which prevent or reduce severity of epileptic or other convulsive seizures

Antiparkinsonian agents

Drugs which control tremors and muscle rigidity
associated with Parkinson disease by
increasing dopamine levels in the brain

Antipsychotics

Drugs which alter neurotransmitters in the brain to alleviate symptoms of psychosis, paranoia, and schizophrenia

General anesthetics

Anesthetics which act on brain to produce complete loss of consciousness

Local anesthetics

Anesthetics which act on nerves or nerve tracts to affect a local area only