Med Term Chap 10: The Nervous System

Caus/o

burning, burn

Cerebr/o

cerebrum, brain

concuss/o

shaken together, violently agitated

contus/o

bruise

encephal/o

brain

-esthesia

sensation, feeling

esthet/o

feeling, nervous sensation, sense of perception

-graphy

the process of producing a picture or record

meaning/o

membranes, menings

myel/o

spinal cord, bone marrow

neur/o, neur/i

nerve, nerve tissue

phobia

Abnormal fear

psych/o

mind

radicul/o

root or never root

tropic

having an affinity for

Central nervous system (CNS)

Function: receive and process information, and to regulate all body activity

Includes brain and spinal cord

Peripheral nervous system (PNS)

Function: transmit nerve signals to and from the CNS

Includes- 12 pairs of cranial nerves extending from the brain and 31 pairs of peripheral spinal nerves extending outward from the spinal cord

Nerve

One or more bundle of neurons that connect the brain and the spinal cord with the other parts of the body

Tract

bundle or group of nerve fibers located within the brain or spinal cord

ganglion

a nerve made up of a cluster of nerve cell bodies outside the CNS

innervation

the supply of nerves to a specific body part

Plexus

Network of intersecting spinal nerves

Receptors

Sites in sensory organs that receive external stimulation. They send the stimulus through the sensory neurons to the brain for interpretation

Stimulus

Anything that excites a nerve and causes an impulse

Reflex

An automatic, involuntary response to some change, either inside or outside the body

Neurons

The basic cells of the nervous system that allow different parts of the body to communicate with each other

Dendrites

The root-like processes that receive impulses and conduct them to the cell body

Axon

Process that conducts impulses away from the nerve cell

Afferent neurons

These emerge from sensory organs and the skin to carry impulses from the sensory organs toward the brain and spinal cord

Aka sensory neurons

Connecting neurons

These neurons link afferent and efferent neurons

Aka associative neurons

Efferent neurons

These carry impulses away from the brain and spinal cord and towards the muscle and glands

Terminal end fibers

The branching fibers at the end of axon that lead the nervous impulse from the axon to synapse

Synapse

The space between two neurons or between a neuron and a receptor organ

Neurotransmitters

Chemical substances that make it possible for messages to cross from the synapse of a neuron to the target receptor

Glial cells

Provide support and protection from neurons

Functions: (1) surround neurons and hold them in place, (2) to supply nutrients and oxygen to neurons, (3) to insulate one neuron from another,(4) to destroy and remove dead neurons

Myelin sheath

The protective covering made of glial cells

From white matter of the brain and covers some parts of the spinal cord and the axon of most peripheral nerves

Menings

The system of membranes that enclose the brain and spinal cord

Dura meter

Thick, tough, outermost layer of menings

Arachnoid meter

Resembles a spiderweb, the second layer of the menings

Pita meter

The third layer of menings, located nearest to the brain and spinal cord

Cerebrospinal fluid

Produced by special capillaries within the four ventricles located in the middle region of the cerebrum

Cerebrum

Largest and the uppermost portion of the brain, responsible for all thought, judgment, memory, and emotions, as well as for controlling and integrating motor and sensory functions

Cerebral

Pertaining to the cerebrum or to the brain

Cerebral cortex

Made up of gray matter, the outer layer of the cerebrum and is made up of elevated folds and deep fissures

Thalamus

Relays sensory stimuli from the spinal cord and midbrain to the cerebral cortex

Located below the cerebrum

Hypothalamus

Controls vital body functions

Located below the thalamus

Cerebellum

Coordinates muscular activity and balance for smooth and steady movements

Located in the lower back of the cranium below the cerebrum

Brain stem

Controls the functions necessary for survival (breathing, digestion, heart rate, and blood pressure), for a arousal (being awake, and alert)

Located in the base of the brain and forms the connection between the brain and spinal cord

Consists: midbrain, pons and medulla oblongata

Midbrain and pons

Provide conduction pathways to and from the higher and lower centers in the brain, also controls reflexes For movements of the eyes and head in response to visual and auditory stimuli

Medulla oblongata

Located at the lowest part of the brain stem, connected to the spinal cord. Controls basic survival functions

Spinal cord

Long, fragile tube-like structure that begins at the end of the brain stem and continues down almost to the bottom of the spinal column

Cranial nerves

The 12 pairs originate from the under-surface of the brain. The two nerves of a pair are identical in function and structure, and each nerve of a pair serves half of the body

Peripheral spinal nerves

Grouped together and named on the region of the body they innervate

Autonomic nervous system

Organized into two division, one comprising sympathetic nerves and the other parasympathetic nerves. It controls the involuntary actions of the body such as the functioning of internal organs

Sympathetic nerves

Prepare the body for emergencies and stress by increasing the breathing rate, heart rate, and blood flow to muscles

Parasympathetic nerves

Returns the body to normal after a response to stress, also maintains normal body function during ordinary circumstances that are emotionally or physical stressful

Anesthesiologist

A physician who specializes in administering anesthetic agents before and during surgery

Anesthetist

A medical professional who specializes in administering anesthesia, but is not a physician, for example, a nurse anesthetist

Neurologist

A physician who specializes in diagnosing and treating diseases and disorders of the nervous system

Neurosurgeon

Physician who specializes in surgery of the nervous system

Psychiatrist

A physician (MD) who specializes in diagnosing and treating chemical dependencies, emotional problems, and mental illness. They can prescribe medications

Psychologist

Has doctoral degree (PhD or PsyD) but is not a medical doctor (MD). This specialist evaluates and treats emotional problems and mental illness

Cephalgia

Pain in the head

Aka headache

Migraine headache

Preceded by a warning aura, is characterized by throbbing pain on one side of the head

Cluster headache

Intensely painful headaches that affect one side of the head and may be associated with tearing of the eys and nasal congestion

Encepahlocele

A congenital herniation of brain tissue through a gap in the skull

Aka craniocele

Meningcele

The congenital herniation of the menings through a defect in the skull or spinal column

Hydrocephalus

A condition in which excess cerebrospinal fluid accumulates in the ventricles of the brain

Meningioma

A common, slow-growing and usually benign tumor of the menings

Meningitis

An inflammation of the meninges of the brain and spinal cord

Aka infectious meningitis

Cognition

Describes the mental activities associated with thinking, learning and memory

Dementia

A slowly progressive decline in mental abilities, including memory, thinking, and judgment, that is often accompanied by personality changes

Senile dementia: dementia of the aged

Vascular dementia

Form of dementia caused by a stroke or other restriction of the flow of blood to the brain.

Encephalitis

An inflammation of the brain, can be caused by a viral infection such as rabies

Reye’s syndrome

A potentially serious or deadly disorder in children that is characterized by vomiting and confusion. This syndrome sometimes follows a viral illness in which the child was treated with aspirin

Tetanus

Acute and potentially fatal infection of the CNS caused by a toxin produced by the tetanus bacteria

Tourette syndrome

A complex neurological disorder characterized by involuntary tics, grunts, and compulsive utterances that sometimes include obscenities

Neurodegenerative disease

An umbrella term for disorders in which there is a progressive loss of the structure or functions of the neurons

Alzheimer’s disease

A group of disorders involving the parts of the brain that control thought, memory and language.

It is the main cause of dementia and is marked by progressive deterioration that affects both the memory and reasoning capabilities of an individual

Parkinson’s disease

Chronic, degenerative central nervous disorder characterized by fine muscle tremors, rigidity and a slow or shuffling gait (manner of walking)

Amnesia

A memory disturbance characterized by a total or partial inability to recall past experiences, can be caused by brain injury, illness, or a psychological disturbance

Concussion

A violent shaking up or jarring of the brain. May result in a temporary loss of awareness and function

Cerebral contusion

The bruising of brain tissue as the result of a head injury that causes the brain to bounce against the rigid bone of the skull

Cranial hematoma

A collection of blood trapped in the tissues of the brain

Traumatic brain injury

A blow to the head or a penetrating head injury that damages the brain

Shaken baby syndrome

The results of a child being shaken by someone, this can cause brain injury, blindness, fractures, seizures, paralysis, and death

Levels of consciousness

Describe the measurement of response to arousal and stimulus

Conscious

The state of being awake, alert, aware and responding appropriately

Unconscious

A state of being unaware and unable to respond to any stimuli, including pain

Lethargy

A lowered level of consciousness marked by listlessness, drowsiness, and apathy

Stupor

An unresponsive state from which a person can be aroused only briefly despite vigorous, repeated attempts

Syncope

The brief loss of consciousness caused by the decreased flow of blood to the brain

Aka fainting

Coma

A profound (deep) state of unconsciousness marked by the absence of spontaneous eye movements, no response to painful stimuli, and the lack of speech

Persistent vegetative state

A type of coma in which the patient exhibits alternating sleep and wake cycles; however, due to severe damage to certain areas of the brain, the person in unconscious even when appearing to be awake

Delirium

An acute condition of confusion, disorientation, disordered thinking and memory, agitation, and hallucinations

Brain tumor

An abnormal growth located inside the skull

Malignant- destroys brain tissues

Benign- does not destroy brain tissues

Intracranial pressure

The amount of pressure inside the skull

Cerebrovascular accident

This condition is damage to the brain that occurs when the blood flow to the brain is disrupted because a blood vessel is either blocked or has ruptured

Commonly known as stroke

Ischemic stroke

The most common type of stroke in older people, occurs when the flow of blood to the brain is blocked by the narrowing or blockage of a carotid artery

Transient ischemic attack

The temporary interruption in the blood supply to the brain

Sometimes referred as a “mini-stroke”