Vestibular evoked myogenic potentials (VEMP) have gained in clinical significance in recent years, now forming an integral part of neurootological examinations to establish the functional status of the otolith organs. They are sensitive to low-frequency acoustic stimuli. When stimulated, receptors in the sacculus and utriculous are activated. By means of reflexive connections, myogenic potentials can be recorded when the relevant muscles are tonically activated. The vestibulocolic (sacculocollic) reflex travels from the otolith organs over the central circuitry to the ipsilateral sternocleidomastoid muscle. Myogenic potentials can be recorded by means of cervical VEMP (cVEMP). The vestibuloocular reflex crosses contralaterally to the extraocular eye muscle. Ocular VEMP (oVEMP) are recorded periocularly, preferably from the inferior oblique muscle. Various stimulation methods are used including air conduction and bone conduction.

VEMP measurements are subject to various influencing factors: patient age, threshold, sound intensity and frequency. Using air (AC) and bone conduction (BC) the vestibular receptors and afferents of the otolith organs can be activated to varying degrees. Recordings of cervical (cVEMP) and ocular VEMP (oVEMP) are clinically possible. AC-cVEMP are primarily an indicator of the sacculocollic reflex pathway. Together with findings on the vestibuloocular reflex (VOR) and complimentary otolith tests, VEMP enable otolith function analysis of each side separately. In addition, the distinction between combined or isolated canal and otolith dysfunction in terms of subtyping and patterns of damage in mono- and bilateral disorders, such as vestibular neuritis or bilateral vestibulopathy, is possible. Moreover, VEMP is relevant in terms of prognostic and therapeutic considerations as well as expert assessments.

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Perturbation of semicircular canal function may result in a pathological angular vestibulo-ocular reflex (aVOR). The resulting impairment in gaze stabilization is perceived as "vertigo" or "dizziness" and may occur following receptor function impairment of all three semicircular canals. The head impulse test reveals hidden (covert-catchup) or visible (overt-catchup) saccades in disturbances of semicircular function. Most peripheral vestibular disorders can be treated conservatively. There are surgical treatment options for some diseases, such as intractable benign paroxysmal positional vertigo and superior semicircular canal dehiscence. Vestibular training promotes central reorganization of the VOR. Impaired semicircular receptor function, in particular bilateral vestibulopathy, may affect spatial orientation and cognitive processes. Balance prostheses could serve as a replacement for receptors in the future.

NIR generates temperature differences and nystagmus. By using a broad scale as well as a monochromatic NIR-emission source, it is possible to generate a nystagmus. The procedure of NIR-irritation occurs without physical contact, is painless and quiet.