The Nervous System

Nervous System

with the brain as its center, coordinates and controls all bodily activities. The major structures of this are nerves, brain, spinal cord, and sensory organs.

Central Nervous System (CNS)

Include brain and spinal cord. Are to receive and process information and regulate all bodily activity.

Peripheral Nervous System (PNS)

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

• Is to transmit nerve signals to and from the central nervous system.

Nerve

Is one or more bundles of neurons that connect the brain and spinal cord with other parts of the body.

Tract

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

Ganglion (benign/tumor-like)

Is a nerve center made up of a cluster of nerve cell bodies outside the central nervous system.

Plexus

is a network of intersecting spinal nerves. This term describes a network of intersecting blood or lymphatic vessels.

Receptors

are sites in the sensory organs (eye, ears, skin, nose, and taste buds) that receive external stimulation. The ___ send the stimulus through the sensory neurons to the brain for interpretation.

Reflex

is an automatic, involuntary response to some change, either inside or outside the body.

-changes heart rate

-coughing/sneezing

Neurons

are the basic cells of the nervous system that allows different parts of the body to communicate with each other.

Dendrites

are the root like processes that received impulses and conduct them to the cell body.

Axon

is a process that conducts impulses away from the nerve cell. It can be 3 feet long. Protected by myelin sheath.

Terminal End Fibers

are the branching fibers at the end of the axon that lead the nerve impulse from the axon to synapse.

Synapse

is the space between two neurons or between a neuron and a receptor organ.

Neurotransmitters

are chemical substances that make it possible for messages to cross from the synapse of a neuron to the target receptors. There are 200-300 known ____ and each has a specialized function.

Glial Cells

provide support and protection for neurons, and their four maintain functions are (1) surround and hold them in place, (2) supply nutrients and oxygen to neurons, (3) insulate 1 neuron from another, (4) destroy and remove dead neurons.

Myelin Sheath

Is the protective covering made up of glial cells. This white sheath forms the white matter of the brain and covers some part of the spinal cord and axons of most peripheral nerves.

Meninges

are the system of membranes that enclose the brain and spinal cord.

dura mater

is the thick, tough, outermost membrane of the meninges.

Arachnoid Membrane

which resembles a spider web, is the second layer of the meninges and is located between the dura mater and pia mater.

Pia Mater

is the third layer of the meninges, located nearest to the brain and spinal cord. Consists of connective tissue that contains a rich supply of blood vessels.

Cerebrospinal Fluid; spinal fluid

is produced by special capillaries within the four ventricles located in the middle region of the cerebrum. It is a clear, colorless, watery fluid that flows throughout the brain and around the spinal cord.

Cerebrum

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

Thalamus

which is located below the cerebrum, produces sensation by relaying impulses to and from the cerebrum and the sense organs of the body.

Cerebellum

is the second largest part of the brain. Located at the back of the head below the posterior portion of the cerebrum. The general functions of this is to produce smooth and coordinated movements, to maintain equilibrium, and to sustain normal postures.

Brainstem

Is the stalk-like portion of the brain that connects the cerebral hemispheres with the spinal cord.

Spinal Cord

is a long, fragile, tube-like structure that begins at the end of the brainstem and continues down almost to the bottom of the spinal column.

Peripheral Spinal Nerves

are grouped together and named based on the region of the body they innervate.

Autonomic Nervous System

is organized into two divisions, (1) comprising sympathetic nerves and (2) parasympathetic nerves. This 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 respiratory rate, heart rate, and blood flow to muscles. Aroused as part of the Fight-or-flight response, body’s natural reaction.

Parasympathetic Nerves

return the body to normal after a response to stress. Also maintain normal body function during ordinary circumstances that are not emotionally or physically stressful.

Migraine Headache

Which may be preceded by a warming aura, is characterized by throbbing pain on one side of the head. Primarily affect women and sometimes accompanied by nausea, vomiting, and sensitivity to light or sound.

Cluster Headache

Are intensely painful headaches that affect one side of the head and may be associated with tearing of the eyes and nasal congestion. Affect men, named for their repeated occurrence in group or clusters.

Encephalocele AKA craniocele

is a congenital herniation of brain tissue through a gap in the skull.

Meningocele

Is the congestinal herniation of meninges through a defect in the skull or spinal column.

Hydrocephalus

is a condition in which excess cerebrospinal fluid accumulates in the ventricles of the brain.

Meningitis AKA infectious meningitis

Is the inflammation of the meninges of the brain and spinal cord. Cause by the bacteria or viral infection elsewhere in the body.

Chiari Malformation

Is a congenital condition in which part of the cerebellum extends down into spinal canal.

Encephalitis

Is an inflammation of the brain, can be caused by viral infection such as rabies.

Reye’s Syndrome

Is a serious and potentially deadly disorder in children that is characterized by vomiting and confusion. Children sometimes treated with aspirin.

Tetanus AKA lockjaw

is an acute and potentially fatal infection of the central nervous system caused by a toxin produced by the tetanus bacteria. Can be prevented by immunization.

Tourette Syndrome

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

Dementia

is a slowly progressive decline in mental abilities, including memory, thinking, and judgement, that is often accompanied by personality changes.

Vascular Dementia

Is a form of dementia caused by stoke or other restriction of the flow of blood to the brain.

Neurodegenerative disease aka Degenerative nerve disease

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

Alzheimer’s Disease

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

Lewy Body Dementia

is the second most common type of dementia, occurs when abnormal proteins interfere with cell function in the brain. Named after Frederic Lewy.

Amyotrophic Lateral Sclerosis AKA Lou Gehrig’s Disease

Is rapidly progressive neurological disease that attacks the nerve cells responsible for controlling voluntary muscle. Patients affected by being weak until they completely paralyzed and die.

Traumatic Brain Injury

is a blow to the head or a penetrating head injury that damages the brain.

Shaken Baby Syndrome

describe the results of a child being violently shaken by someone. This action can cause brain injury, blindness, fractures, seizures, paralysis, and death.

Lethargy

Is a lowered level of consciousness marked by listlessness, drowsiness, and apathy.

Stupor

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

Syncope AKA Fainting

is the brief loss of consciousness caused by a decreased flow of blood to the brain.

Persistent Vegetative State

is a type of coma in which the patient exhibits alternating sleep and wake cycle. Due to severe damage to certain areas of the brain, the person is unconscious even when appearing to be awake.

Delirium

Is an acute condition of confusion, disorientation, disordered thinking and memory, agitation, and hallucination. Also known as Neurocognitive disorder

Glioblastoma AKA glioblastoma multiforme

Is a type of fast-growing, malignant brain tumor that forms from glial cells.

Stroke aka Cerebrovascular accident

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

Ischemic Stroke

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 an artery.

Transient Ischemic Attack aka Mini Stroke

is a temporary interruption in the blood supply to the brain. Symptoms of these are; numbness, blurred vision, dizziness, or loss of balance. Happens less than an hour.

Aphasia

Which is often caused by brain damage associated with a stroke, is the loss of ability to speak, write, and/or comprehend the written or spoken word.

Hemorrhagic Stroke aka Bleed

occurs when blood vessel in the brain leaks. Also occurs when an aneurysm within the brain ruptures.

Arteriovenous Malformation

is one of the causes of hemorrhagic stroke. This abnormal connection between arteries and veins in brain that usually congenital and can rupture suddenly at any age.

Polio aka Poliomyelitis

is highly contagious viral infection of the brainstem and spinal cord that sometimes leads to paralysis.

Radiculitis aka Pinched Nerve

Inflammation of the root of a spinal nerve that causes pain and numbness radiating down the affected limb.

Multiple Sclerosis

is a progressive autoimmune disorder characterized by inflammation that causes demyelination of the myelin sheath. Scars the brain, spinal cord, and optic nerves…

Bell’s Palsy

is the temporary paralysis of the seventh cranial nerve that causes paralysis of the face, only on the affected side. Symptoms like inability to close eye, tearing, pain, drooling…

Guillain- Barre Syndrome

Is an inflammation of the myelin sheath of peripheral nerves, characterized by rapidly worsening muscle weakness that can lead to temporary paralysis. A rare condition.

Cerebral Palsy

Is a group of disorders characterized by poor muscle control, spasticity, speech defects, and other neurologic deficiencies due to damage that affects the cerebrum.

Epilepsy aka Seizure disorder

Is a chronic neurological condition characterized by recurrent episodes of seizures of varying severity. Can be controlled with medications.

Seizure

Is a sudden surge of electrical activity in the brain that affects how a person feels or acts for short time. Some can hardly noticed, others loss consciousness.

Absence Seizure aka Patit Mal Seizure

is a brief disturbance in brain function in which there is a loss of awareness often describe as a staring episode.

Febrile Seizure

occurs in infants and young children in response to a fever. most children outgrow this by age 5.

Sudden Unexpected Death in Epilepsy (SUDEP)

refers to the death of someone with epilepsy, usually during or immediately following a seizure. The cause of this is unknown, but maybe related to respiratory failure or cardiac arrythmias.

Causalgia

Is persistent, severe burning pain that usually follows an injury to a sensory nerve.

Complex Regional Pain Syndrome (CRPS)

Is a chronic nerve pain affecting one limb usually following an injury. Characteristic of this is changes in skin color, temperature, swelling of affected limbs.

Restless Legs Syndrome

Is a neurological disorder of unknown cause characterized by uncomfortable feelings in the legs, producing a strong urge to move them. Most noticeable at night or resting.

Functional MRI

detects changes in the blood flow in the brain when the patient is asked to perform a specific task. It gives clearer picture of the brain tissue relevant to the task.

Electroencephalography

Is the process of recording the electrical activity of the brain through the use of electrodes attached to the scalp. Resulting records called electroencephalogram.

Lumbar Puncture aka spinal Tap

is the process of obtaining a sample of cerebrospinal fluid by inserting a needle into the subarachnoid space of the lumbar region to withdraw fluid.

Barbiturates

are a class of drugs whose major action is a calming or depressed effect on the central nervous system.

Sedative

Depressed the central nervous system to produce calm and diminished responsiveness without producing sleep.

Anesthesia

Is the absence of normal sensation, especially to pain, that is induced by administration of an anesthetic gel.

General Anethesia

involves the total loss of body sensation and consciousness indued by anesthetic agents administered primarily by inhalation or intravenous injection.

Spinal Anesthesia aka Spinal Block

Is regional anesthesia produced by injecting medication into the subarachnoid space.

Deep Brain Stimulation (DBS)

is a neurosurgical procedure used in treatment of dystonia, tremors, and Parkinson’s disease.

Stereotactic Radiosurgery

uses three- dimensional coordinate system to accurately find small tumors within the body, In the brain, breast and deliver radiation directly to them while minimizing damage surrounding the tissue. EX: gamma knife surgery

Electroconvulsive Therapy aka Electroshock Therapy

is a procedure in which small amounts of electric current are passed through the brain, deliberately triggering a brief seizure in order to reverse symptoms of certain mental illness or Parkinson’s motor function.

Transcranial Magnetic Stimulation

use briefly, powerful electromagnetic pulses to alter electrical pathways in the brain. Used to treat severe depression.

Radiofrequency Ablation aka Rhizotomy

Is a minimally invasive procedure that relieve chronic nerve pain by burning part of the nerves, preventing the transmission of pain signals.

Neurotomy

Is the surgical division or dissection of nerve. Used to relive pain or suppress tremors.