Dizziness: Encyclopedia - Dizziness

Dizziness

Dizziness (Latin: "Vertigo") is the sensation of instability. The term is fairly vague, and can include a number of more specific conditions, ranging from harmless to life-threatening. One of the most common causes of dizziness is rapid spinning; this cause lent its name to the baseball pitcher Dizzy Dean, whose windup while throwing the ball caused him to spin completely around.

Vertigo refers to dizziness with a sensation of motion. The cerebellum takes input about the location and motion of the head from the inner ears, the visual system, and position sensors in the neck. If these signals disagree with one another, or if the processing is not working right, vertigo is experienced. Vertigo is more likely than other types of dizziness to be associated with nausea, vomiting, or double vision, to occur even when lying down, and to feel better with the eyes closed. Pilots experiencing vertigo conditions become spatially detached from their aircraft's flight attitude and it can result in loss of control.

Instability is not necessarily dizziness; uneasiness during walking or standing is often due to musculoskeletal pain, Parkinson's disease or various other conditions.

Neurological dizziness is not due to spinning around, standing up-side-down or motion sickness. It is a light-headed sensation in which there is a head-ache and reduced consciousness. This can be accompanied by seeing stars, blacking out, convulsions, fainting, paralysis and other neurological symptoms. Take note that the dizziness caused by fainting is different from that of dizziness caused by spinning too fast. It is a different sensation. The stars (white spots that appear to move infront of the eyes), colvulsions, and confusion is often the result of excessive neuronal discharges often caused by the chemical glutamate. Oxygen deprivation can result in excessive neurological discharge leading to brain damage or/and convulsions due to glutamate after prolonged periods or about minute.

Dizziness - Causes

Inner ear causes:

• benign paroxysmal postural vertigo
• labyrinthitis
• Meniere's disease
• perilymphatic fistula
• neurinoma of the acoustic nerve
• vestibular neuronitis

Eye causes:

• new glasses
• optical illusions

Neck causes:

• arthritis
• cervical vertigo
• Whiplash and other strains

Central nervous system causes:

• arteria basilaris syndrome
• concussion
• migraine
• multiple sclerosis
• orthostatic hypotension
• stroke

Breathing causes:

• Extreme Intake of Helium
• Hyperventilation [breathing too fast]

See also

• motion sickness

Other causes: Low blood pressure and /or hyperventilation (often situational), such as emotionally-induced "fainting". Some persons may have deliberately or subconsciously "learnt" to induce such "dizziness" symptoms or complaints. Further medical tests may be needed to determine whether there is indeed a true medical cause. If the "dizziness" is psychosomatically linked, then cognitive and "play" therapies may introduce other ways of coping with strange, stressful and unusual situations.

Adapted from the Wikipedia article "Dizziness", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki