This paper presents a functional architecture, system level design, and electronic evaluation of a unilateral vestibular prosthesis. The sensing unit of the prosthesis is a custom-designed one-axis micro-electromechanical system (MEMS) gyroscope. Similar to the natural semicircular canal, the MEMS gyroscope senses angular motion of the head and generates voltages proportional to the correspondi...

UNLABELLED Glucose metabolism has a significant impact on inner ear physiology, and small changes may result in hearing and balance disorders. AIM To investigate vestibulocochlear symptoms in patients with type I diabetes mellitus. STUDY DESIGN a cross-sectional study of a contemporary group. MATERIAL AND METHOD 30 patients referred from Clinical Hospital-UFPR to the Laboratory of Otoneur...

The relative simplicity of the neural circuits that mediate vestibular reflexes is well suited for linking systems and cellular levels of analyses. Notably, a distinctive feature of the vestibular system is that neurons at the first central stage of sensory processing in the vestibular nuclei are premotor neurons; the same neurons that receive vestibular-nerve input also send direct projections...

Previous experiments have demonstrated that the vestibular system contributes to regulating sympathetic nervous system activity, particularly the discharges of vasoconstrictor fibres. In the present study, we examined the physiological significance of vestibulosympathetic responses by comparing blood flow and vascular resistance in the forelimb and hindlimb during head-up tilt from the prone po...

We investigated the effects of an electro-tactile vestibular substitution system (EVSS) on upright postural control in 12 unilateral vestibular-defective patients. The underlying principle of this system consists in supplying the user with additional information about his/her head orientation/motion with respect to gravitational vertical, normally provided by the vestibular system, through elec...

Elevated levels of stress and anxiety often accompany vestibular dysfunction, while conversely complaints of dizziness and loss of balance are common in patients with panic and other anxiety disorders. The interactions between stress and vestibular function have been investigated both in animal models and in clinical studies. Evidence from animal studies indicates that vestibular symptoms are e...

Histaminergic drugs have long been used to treat balance disorders in man, but their mechanisms of action in the vestibular system are poorly understood. In this article we review the current literature on histaminergic neurotransmission in the brain focussing particularly in the brainstem vestibular nuclei, and the role of histamine in brain plasticity during "vestibular compensation", the beh...

The vestibular system detects motion of the head and maintains stability of images on the fovea of the retina as well as postural control during head motion. Signals representing angular and translational motion of the head as well as the tilt of the head relative to gravity are transduced by the vestibular end organs in the inner ear. This sensory information is then used to control reflexes r...

Eye movements were recorded in the pigmented rat during vestibular, optokinetic and combined visual-vestibular stimulation. The dominant time constant in pigmented rats, tested during angular vestibular stimulation in darkness, is about two times longer than the cupular time constant. The gain and the duration of nystagmus, achieved by angular vestibular stimulation, can be enhanced by visual i...

Posttraumatic stress disorder (PTSD) is a chronic and disabling, anxiety disorder resulting from exposure to life threatening events such as a serious accident, abuse or combat (DSM IV definition). Among veterans with PTSD, a common complaint is dizziness, disorientation and/or postural imbalance in environments such as grocery stores and shopping malls. The etiology of these symptoms in PTSD i...