Pathophysiology of Vertigo

      Vertigo arise if there is a disruption of the body's balance tool caused a discrepancy between body position (afferent information) actually with what are perceived by the central nervous system (central consciousness). The most important afferent arrangement in this system is, vestibular or balance, array, which is continuously delivers its impulse to the center of balance. Other arrangement that role is an optical system, and proprioceptive, poles connecting the poles vestibular nuclei with nuclei N. III, IV and VI, the vestibulo reticular and vestibulospinal arrangement. Information that is useful to balance the body would be arrested by the receptors vestibular, visual, and proprioceptive; vestibular receptors biggest contributing, that more than 50%, followed later visual receptors and the smallest contribution is proprioceptive.

       Conditions physiological / normal information arrived in the center of integration tools from the balance receptors vestibular, visual and proprioceptive left and right will be compared, if everything is in a state of synchronous and reasonable, will be processed further. The response appears in the form of adjustment of the eye muscles and motor body in motion. In addition, people are aware of the position of the head and body to the surrounding environment. If the function of the balance organs in the peripheral or central in a state of normal / not physiological, or there is a strange movement stimuli or excessive, then the processing of information would be disturbed, resulting in symptoms of vertigo and autonomic symptoms. In addition, the response to be inadequate muscle adjustments that appear to be abnormal movements nystagmus, unsteadiness, ataxia when standing / walking and other symptoms.

There are several theories that seek to explain the incidence of body imbalances:
1. Excessive stimulation theory (overstimulation)
This theory is based on the assumption that excessive stimulation causes hyperemia semicircular canals that function is impaired; consequences will arise vertigo, nystagmus, nausea and vomiting.

2. Sensory conflict theory
According to this theory there is a mismatch of sensory input from a wide range of peripheral sensory receptors, ie between the eyes / visual acuity, vestibule and proprioceptive, or imbalance / asymmetry of sensory input from the left and right. Incompatibility is causing confusion in the central sensory response that arise can be nystagmus (eye correction effort), ataxia or difficulty walking (vestibular disorders, cerebellum) or the sensation of floating, rotating (derived from cortical sensation). In contrast to theories overstimulation, this theory emphasizes the central processing disorder as the cause.

3. The theory of neural mismatch
  This theory is the development of the sensory conflict theory: according to this theory the brain has a memory of a specific movement patterns; so that if at any point felt a strange movement / does not match the pattern of movements that have included memory, a reaction of the autonomic nervous system.  If  the new movement pattern repeated, there will be mechanisms of adaptation, so that is no longer gradual onset of symptoms. 

4. Autonomic theory.
  This theory emphasizes changes in the autonomic nervous system reactions as adaptation efforts motion / position changes, clinical symptoms arise if the system is too dominant sympathetic, parasympathetic otherwise be lost if the system comes into play.

5.  Neurohumoral theory
Among histamine theory (Takeda), dopamine theory  (Kohl) and serotonin theory  (Lucat), each of which emphasizes the role of certain neurotransmitters in the autonomic nervous system influence causing vertigo symptoms.

6. SynapsesTheory .
An earlier theory that the development of neurotransmission and reviewing the role of biomolecular changes that occur in the process of adaptation, learning and memory. Bowel movements will cause stress which triggers the secretion of CRF (corticotropin releasing factor), elevated levels of CRF will further activate the sympathetic nervous system which in turn sparked the adaptation mechanisms such as increased activity of the parasympathetic nervous system. This theory can explain the accompanying symptoms that often arise in the form of pale, sweating in the early attack of vertigo caused by sympathetic activity, which developed into symptoms of nausea, vomiting and hypersalivation after a while due to the dominance of the parasympathetic nervous system activity.

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