Search results for "VESTIBULAR"
showing 10 items of 183 documents
The role of the thalamus in the human subcortical vestibular system1
2014
Most of our knowledge concerning central vestibular pathways is derived from animal studies while evidence of the functional importance and localization of these pathways in humans is less well defined. The termination of these pathways at the thalamic level in humans is even less known. In this review we summarize the findings concerning the central subcortical vestibular pathways in humans and the role of these structures in the central vestibular system with regard to anatomical localization and function. Also, we review the role of the thalamus in the pathogenesis of higher order sensory deficits such as spatial neglect, pusher syndrome or thalamic astasia and the correlation of these p…
General remarks on the role of the vestibular system in weightlessness
1987
Different methods are described to experimentally achieve weightlessness. Since the function of the otolith system depends on the presence of contact forces opposing gravity, it is disabled in weightlessness and may send misleading positional information to the brain. Without the contributions of the otolith system it is difficult in space to distinguish self-motion from object motion. Furthermore, the disintegration of information from the neck position receptors from those of the otolith system can lead to additional illusory positional sensations. Since the function of the semicircular canal system in previous space flights was found to be essentially undisturbed, the vestibular experime…
Responses to eccentric rotation in two space-bound subjects
1993
Two subjects were rotated eccentrically in the manner described previously. In contrast to a normal control group, settings of a luminous line to the subjective vertical were almost unrelated to the gravitoinertial vector before, and totally so shortly after, space flight. Only 3 days postflight did a clear relation to the gravitoinertial vector re-establish itself in the one subject who actually flew. The correspondence became normal 5 days after the flight. Since there were no clinical abnormalities evident in the subjects, it is suggested that both subjects suppressed their vestibular information, presumably as an effect of vestibular deconditioning training before the flight. In additio…
Threshold-based vestibular adaptation to cross-coupled canal stimulation
2008
Prior experiments have demonstrated that people are able to adapt to cross-coupled accelerations associated with head movements while spinning at high rotation rates (e.g., 23 rpm or 138°/s). However, while adapting, subjects commonly experience serious side effects, such as motion sickness, non-compensatory eye movements, and strong and potentially disorienting illusory body tilt or tumbling sensations. In the present study, we investigated the feasibility of adaptation using a threshold-based method, which ensured that the illusory tilt sensations remained imperceptible or just barely noticeable. This was achieved by incrementally increasing the angular velocity of the horizontal centrifu…
Vertigo, Masseter Paresis or Masseter Reflex Abnormality, and Impaired Caloric Response
1993
Symptoms and signs of acute peripheral-type vestibular abnormalities occasionally occur in patients with multiple sclerosis and brain-stem ischemia. Such patients may show reduced excitability of the lateral semicircular canal. From this observation, the question arises as to the location of the causative lesion.
Vaskulärer Schwindel
2002
Ischemia,hemorrhages, and other vascular disorders can result in various central or peripheral vestibular syndromes with vertigo, oculomotor/balance disturbances, and nausea. The vascular vertigo syndromes listed in Table 1 can however be brought about by other causes such as demyelitizing focuses in multiple sclerosis or space-occupying lesions, so that not only localization of the damaged structure but also the various etiologies are decisive for the choice of therapy. Occasionally, combined functional disturbances of the peripheral and central vestibular system appear, such as an infarction of the inferior anterior cerebellar artery, which supplies the labyrinth and parts of the brainste…
Easy, Inexpensive, and Effective: Vestibular Exercises for Balance Control
2004
The convincing study by Yardley and colleagues in this issue broadens our knowledge of treating dizziness and provides strong arguments to get our patients up and exercising.
Solitary Vestibular Schwannoma: Decision Making of Treatments
2012
Therapeutic strategies of vestibular schwannomas treatment are changed in the last years. The improvement of surgical equipments and skills allowed increasing the numbers of successful operations in the last 10 years. The results improved in terms of survival, quality of life, recurrences, facial nerve function, and hearing preservation. Also the age of operated patients, once a restriction, becomes progressively a relative limitation to surgical indication. However the progressive widening of MRI availability give to the Otoneurologist the possibility to follow-up the patients with a relative simple radiological examination, delaying the decision to treat surgically the neoplasm only in ca…
Intralabyrinthine neurinoma: Management, exeresis and auditory restoration with cochlear implant
2021
Abstract Background and objective Vestibular schwannoma is a benign tumour that originates in the eighth cranial nerve. It is termed intralabyrinthine schwannoma (ILS) when it develops in the inner ear, this being a rare origin. We present our experience in the management of three patients with ILS. Materials and methods The results of tumour excision and cochlear implantation were evaluated in three patients with ILS: two intracochlear schwannomas (ICS) and one intravestibular schwannoma (IVS). Results Prior to surgery, all patients presented progressive sensorineural hearing loss and tinnitus. Complete tumour resection and cochlear implantation was possible in all patients, with favourabl…