The technical explanation of what is going on follows: The vestibular system functions to provide: (1) spatial orientation at rest or during acceleration, (2) visual fixation during head and/or body movement (the vestibulo-ocular reflex), and (3) feedback control of muscle tone to maintain posture. These functions and their control mechanisms are interconnected in a complex fashion. Thus, the symptoms of episodic vertigo reflect disturbances in more than one system. The combination of multiple sensory deficits (Brandt 1991) can produce disorientation or disequilibration that is interpreted as dizziness or vertigo. This often occurs in the elderly, in whom vision (cataracts), hearing (presbycusis), and proprioception (peripheral neuropathy) may all be impaired. There is an entity known as presbylibrium or imbalance resulting from aging which may be due to a selective progressive deterioration of the peripheral vestibular apparatus or a combination of sensory deficits.

Even an intact person is easily confused by afferent sensory information, as exemplified by the sensation of spinning or true vertigo experienced during full-field optokinetic stimulation. Almost every individual, while quietly seated, will experience a compelling illusion of rotation while viewing a moving environment of optokinetic stripes (the circular-vection illusion). Thus, it is not surprising that patients with subtle abnormalities of peripheral or central vestibular mechanisms experience definite momentary periods of disorientation while viewing a moving patterned environment. Some experience episodic vertigo during vehicular travel.

The age-related degeneration of vestibular receptors, presbylibrium, contributes to vertigo. Although most younger patients readily compensate for unilateral peripheral vestibular damage, older patients frequently cannot or have very gradual improvement, indicating either bilateral peripheral vestibular dysfunction or a separate central abnormality that decreases their ability to compensate.

Thus many people who have multiple sensory defects are in fact, "dizzy" or "imbalanced" due to the subtle combination of different sensory defects. Medication is usually not helpful unless there is clear episodic vertigo (spinning) due to inner ear dysfunction. Patients can be helped however, by increasing their sensory input by using a "dragging cain". Using a cane, not to support a weak leg, but by dragging it along the ground, increases sensory input through the arm where the cane is held. The individual has a better sense of stability and "where the ground is" and many times can walk more steadily and safely.