(Jrt)
Dizziness
Two types of sensations dizziness are commonly named:
The true vertigo, corresponding to the rotation and nauseous sensation caused by a perception of movement between different vision and the vestibular organ.
The dizziness, without sensation of rotation, attached to many clinical syndromes, without specific net, including one can count malaise, the HTA, hypotension, fever, (non-exhaustive list).
Dizziness, feeling of unease and anxiety when the subject is in height, is a phenomenon from which the correct name is acrophobia.
Pathophysiology
The concept of vertigo is strongly associated with that movement in space. The body perception of these movements is the vestibular system, located in the inner ear. The latter receives a movement that is often also seen through the eyes so that even if this movement can be felt as unpleasant (for example, when in a roller coaster), it does not conflict with information from the visual path.
The vertigo comes from the disagreement between the movement seen and the movement perceived by the inner ear. If the inner ear perceives a movement not passed by the vision, then the dizziness occurs, with its procession nauseous.
Under the vertigo true, it can be two types:
The physiological vertigo, in which the discomfort is caused by the confrontation of the duo vision / vestibule with a situation / conformation unusual. Vertigo at the top of the scale or the Eiffel Tower is classified in this category. Similarly, if you handle a child 2 years old in your arms, moving from one position to another, possibly even bringing it to both arms above you, this is most often present no problem, the child often being manipulated by adults arm. If you repeat the experiment with the same child as an adult, biped to life without acrobatics calm during 70 years, a person of 72 years, it is plausible to observe a much more limited tolerance.
The pathological vertigo, caused by a pathology of vestibular or visual perception, or at least a difference between the two perceptions. The anomaly of perception, both visual vestibular that may occur in the perception and in neurological transmission of the message, as finally in the processing of information at the visual cortex and vestibular, or in their relationship.
Read also Ear
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