MS Glossary

A B C D E F G H I  L M N O P Q R S T U V W


Paralysis - Inability to move a part of the body. #28

Paraparesis - A weakness but not total paralysis of the lower extremities (legs). #28

Paresis - Partial or incomplete paralysis of a part of the body. #28

Paresthesias - (Gr.- para = abnormal, aisthesis = sensation) Sensations of Burning, Prickling, Creeping on the Skin, or "Pins-and-Needles" that develop with damage to a Pain Pathway (Axon). Which may or may not be associated with any physical findings on Neurological Examination. #25

- Lesions or damage in the Dorsal Columns (Spinal Cord) often register as tingling and numbness, due to irritation of Sensory Nerve fibers, as they die. These sensations range from merely annoying to severe pain. In some cases, even the light touch of clothing, can be painful.

Paroxysmal Symptom - Any one of several symptoms having a Sudden Onset, in response to some kind of movement or Sensory Stimulation, last for a few moments, and then subside. They are thought to be caused by the short-circuiting of electrical impulses along DeMyelinated Axons. #28
(Also See: L'hermitte's Sign, Trigeminal Neuralgia)

Peptide - Short strings (groups) of Amino Acids, which Immune Cells (Leukocytes) use to identify Cells, as belonging to Self or Antigen. #30

Peripheral Nervous System - All the Nerves and Nerve Cells outside the Central Nervous System. #01

PeriVentricular Region - The area surrounding the four fluid-filled cavities (Ventricles) within the Brain. MS plaques are commonly found within this region. #28

Phagocyte - A PolyMorphoNuclear Leukocyte that consumes cellular debris and invading MicroOrganisms. Neutrophils, Dendrites, and Macrophages are Phagocytes or eating cells (phago = "eating", cyte = "cell").

- These APCs present Antigens on their cell surfaces that are the chemical remains (Peptide) of the Organism. Antigens presented in this way activate specific responses and destroy the invading Organism. #30

Phagocytosis - The engulfment, digestion, and subsequent processing of debris or a MicroOrganism by Antigen Presenting Cells. #30   (Also See: Phagocytosis)

PhosphoLipids - Are fatty substances that are a major component of Myelin. #27

Pituitary Gland - (often called the master gland) is located in a small bony cavity at the base of the Brain, it has two Lobes: the Anterior and Posterior Lobes.

- The Anterior Pituitary is Glandular. A stalk links the Pituitary to the HypoThalamus, which controls release of Pituitary Hormones. The Posterior Pituitary is used to store Hormones until they are needed. (Also See: GlucoCorticoid Hormones

Placebo Effect - The apparently beneficial result of a medication or other therapy that has no proven value or effect in the management of a medical problem. The apparent benefits occur because of an individual's expectation that the therapy will help. Some people respond to the placebo or sham treatment simply because they are convinced that they have been given the real treatment, and may even have a real physical reaction to the placebo. #25

Plantar Reflex - A Reflex Response obtained by drawing a pointed object along the outer border of the sole of the foot from the Heel to the little Toe. The normal Flexor Response is a bunching and downward movement of the Toes. An upward movement of the big Toe is called an Extensor Response, or Babinski's Sign, which is a sensitive indicator of disease (Spasticity) in the Brain or Spinal Cord. #28

Plaque - The Scarring of Neural tissue that develop after DeMyelination and Lesions. #01

Prednisone - A Steroid drug related chemically and therapeutically to the Steroid Hormones normally made in the Adrenal Glands. Prednisone and other Steroid medications carry significant Long-Term Risks. #25

Pons - The portion of the BrainStem just Superior to the Medulla Oblongata, is about 2.5cm. in length. It contains the Respiratory Center, which controls the mechanism that permits Outflow of air from the Lungs. #20

Posterior Column - Bundle of Axons in the Posterior part of the Spinal Cord. Interruption of this column on one side of the Spinal Cord causes loss of Position Sense below the level of the interruption on the Same Side of the body. #01 (View Image)

Prevalence - The number of all new and old cases of a disease in a defined population at a particular point in time. #28

Primary/Progressive MS - A clinical course of MS characterized from the beginning by progressive Disability, with no plateaus or remissions or an occasional plateau and very short-lived, minor improvements. #28

Prognosis - Predicting the future course of a disease. The following factors are most predictive of outcome in MS: #28

  • Favorable Prognosis
    1. Onset before 30 years of age
    2. Being a female
    3. Complete recoveries - no disability
    4. Sensory System involvement at onset:
    5. Longer first inter-attack interval

Also See: Natural history of Multiple Sclerosis

Progressive/Relapsing MS - A rare type of MS that shows disease progression (increased Disability) from onset, but with clear, acute relapses, with or without full recovery after each relapse. #29, #28

Prospective Memory - The ability to remember an event or commitment planned for the future. Thus, a person who agrees to meet or call someone at a given time on the following day, must be able to remember the appointment when the time comes. Both Prospective and Recent Memory are frequently major Cognitive problems for MSers. #28

Proteins - A group of complex organic compounds, composed of Amino Acids, with defined three-dimensional structures (encoded in DNA) that controls its particular function. Proteins are responsible for all reactions and activities of Cells. #01

Pseudo-Exacerbation - A temporary aggravation of disease symptoms, resulting from an elevation in body temperature or other stressor (ex. an infection, fatigue, heat, or constipation), that disappears once the stressor is removed. A pseudo-exacerbation involves only pre-existing symptoms (flare-up), rather than new disease activity or progression. #28

Pyramidal Tract (CorticoSpinal) - One of the major Motor Tracts from the Brain to the Spinal Cord. The Pyramidal System is specialized for making discrete movements, its Axons form the Pyramids of the Medulla Oblongata. It originates in the Cortex of the Frontal Lobe. #01
  • It communicates directly with Motor Neurons in the Spinal Cord, to activate Fine Motor Control. Ex: tying shoelaces, writing, etc.
  • It orchestrates the Motor Response and helps to Specify Body Posture at all levels of the Spinal Cord.
  • It Adjusts Muscle Tone to counter the changing centers of gravity.
- Plaque here causes the symptoms of Spasticity: Muscle Tightness, Ankle Clonus, Flexor Spasms, Exhaustion, Loss Of Muscle Power, and Paralysis. #02

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