Добірка наукової літератури з теми "Vestibular activities"

Otolaryngologists often prescribe head movement exercise programs for patients with vestibular disorders, although the effectiveness of these programs and the critical features of the exercises are poorly understood. Because many patients who dislike exercising do not follow through with their exercises, alternatives to the traditional repetitive exercises would be useful. Subjects diagnosed with vestibular disorders were treated for 6 weeks with either an outpatient exercise program that incorporated interesting, purposeful activities or a simple home program of head movements, comparable with the exercises otolaryngologists often give their patients when they do not refer to rehabilitation. Both treatments incorporated repetitive head movements in all planes in space, graduated in size and speed. Subjects were all tested before and after treatment with standard measures of vestibulo-ocular reflex and balance, level of vertigo, gross motor skills, and self-care independence. Subjects in both groups improved significantly on the functional measures, with slightly greater improvements in the occupational therapy group. The results were maintained 3 months after the cessation of intervention. These data suggest that graded purposeful activities are a useful alternative for treating this patient population and that the essential factor in any exercise program is the use of repetitive head movements.

This article summarizes six recent degree-of-freedom studies of visual-vestibular interaction during natural activities and relates the findings to canalotolith interactions evaluated during eccentric axis rotations. Magnetic search coils were used to measure angular eye and head movements of young and elderly subjects. A flux gate magnetometer was used to measure three-dimensional head translation. Three activities were studied: standing quietly, walking in place, and running in place. Each activity was evaluated with three viewing conditions: a visible target viewed normally, a remembered target in darkness, and a visible target viewed with x2 binocular telescopic spectacles. Canal-otolith interaction was assessed with passive, whole-body, transient, and steady-state rotations in pitch and yaw at multiple frequencies about axes that were either oculocentric or eccentric to the eyes. For each rotational axis, subjects regarded visible and remembered targets located at various distances. Horizontal and vertical angular vestibulo-ocular reflexes were demonstrable in all subjects during standing, walking, and running. When only angular gains were considered, gains in both darkness and during normal vision were less than 1.0 and were generally lower in elderly than in young subjects. Magnified vision with x2 telescopic spectacles produced only small gain increases as compared with normal vision. During walking and running all subjects exhibited significant mediolateral and dorsoventral head translations that were antiphase locked to yaw and pitch head movements, respectively. These head translations and rotations have mutually compensating effects on gaze in a target plane for typical viewing distances and allow angular vestibulo-ocular reflex gains of less than 1.0 to be optimal for gaze stabilization during natural activities. During passive, whole-body eccentric pitch and yaw head rotations, vestibulo-ocular reflex gain was modulated as appropriate to stabilize gaze on targets at the distances used. This modulation was evident within the first 80 msec of onset of head movement, too early to be caused by immediate visual tracking. Modeling suggests a linear interaction between canal signals and otolith signals scaled by the inverse of target distance. Vestibulo-ocular reflex performance appears to be adapted to stabilize gaze during translational and rotational perturbations that occur during natural activities, as is appropriate for relevant target distances. Although immediate visual tracking contributes little to gaze stabilization during natural activities, visual requirements determine the performance of vestibulo-ocular reflexes arising from both canals and otoliths. (Otolaryngol Head Neck Surg 1998;119:78-88.)

OBJECTIVE: We sought to determine the effectiveness in decreasing some symptoms, such as vertigo, and increasing performance of daily life skills after vestibular rehabilitation. STUDY DESIGN AND SETTING: Patients who had chronic vertigo due to peripheral vestibular impairments were seen at a tertiary care center. They were referred for vestibular rehabilitation and were assessed on vertigo intensity and frequency with the use of the Vertigo Symptom Scale, the Vertigo Handicap Questionnaire, the Vestibular Disorders Activities of Daily Living Scale, and the Dizziness Handicap Inventory. They were then randomly assigned to 1 of 3 home program treatment groups. RESULTS: Vertigo decreased and independence in activities of daily living improved significantly. Improvement was not affected by age, gender, or history of vertigo. CONCLUSION: For many patients a simple home program of vestibular habituation head movement exercises is related to reduction in symptoms and increasing independence in activities of daily living.

Background: Postural stability depends on the integration of multisensory inputs to drive motor outputs. When visual and somatosensory input is available and reliable, this reduces the postural control system’s reliance on the vestibular system. Despite this, vestibular loss can still cause severe postural dysfunction (1,2). Training one or more of the three sensory systems can alter sensory weighting and change postural behavior. Vestibular activation exercises, including horizontal and vertical headshaking, influence vestibular-ocular and -motor responses and have been showed to be effective in vestibular rehabilitation (3–8). Purpose/Hypothesis: To assess sensory reweighting of postural control processing and vestibular-ocular and -motor responses after concurrent vestibular activation with postural training. It was hypothesized that the effect of this training would significantly alter the pattern of sensory weighting by changing the ratio of visual, somatosensory and vestibular dependence needed to maintain postural stability, and significantly decrease vestibular responses. Methods: Forty-two young healthy individuals (22 females; 23.0+3.9 years; 1.6+0.1 meters) were randomly assigned into four groups: 1) visual feedback weight shift training (WST) coupled with an active horizontal headshake (HHS), 2) same WST with vertical headshake (VHS), 3) WST with no headshake (NHS) and 4) no training/headshake control (CTL) groups. The headshake groups performed an intensive body WST together with horizontal or vertical rhythmic headshake at 80 to 120 beats/minute. The NHS group performed the WST with no headshake while the controls did not perform any training. Five 15-minute training sessions were performed on consecutive days for one week with the weight shift exercises involving upright limits of stability activities on a flat surface, foam or rocker board (Fig. 1). All groups performed baseline- and post-assessments including sensory organization test (SOT) and force platform ramp perturbations, coupled with electromyographic (EMG) recordings. A video head impulse test was also used to record horizontal vestibulo-ocular reflex (VOR) gain. A between- and within-group repeated measures ANOVA was used to analyze five COP sway variables, the equilibrium and composite scores and sensory ratios of the SOT as well as EMG signals and horizontal VOR gain. Similarly, COP variables, EMG, as well as vestibular reflex data (vertical VOR, vestibulo-collic reflex [VCR] and vestibulo-spinal [VSR] gains) during ramp perturbations were analyzed. Alpha level was set at p<.05. Results: The training showed a significant somatosensory downweighting (p=.050) in the headshake groups compared to the other groups. Training also showed significant decreased horizontal VOR gain (p=.040), faster automatic postural response (p=.003) (Figs. 2-4) with improved flexibility (p=.010) in the headshake groups. Muscle activation pattern in medial gastrocnemius (p=.033) was significantly decreased in the headshake. Conclusion: The concurrent vestibular activation and weight shift training modifies vestibular-dependent responses after the training intervention as evidenced in somatosensory downweighting, decreased VOR gain, better postural flexibility and faster automatic postural response. Findings suggest this is predominantly due to vestibular adaptation and habituation of VOR, VCR and VSR which induced sensory reweighting. Clinical relevance: Findings may be used to guide the development of a vestibular-postural rehabilitation intervention in impaired neurological populations, such as with vestibular disorders or sensory integration problems.

Vestibular symptoms are symptoms that interfere with daily activities. Diagnosing these symptoms often relies on radiologic examinations that lead to a false negative. Proper clinical approach and study showed higher accuracy than radiologic examination on vestibular disease. These clinical approaches are based on time, triggers, and targeted analysis. The new vestibular symptoms will be classified into acute vestibular syndrome, episodic vestibular syndrome, and chronic vestibular syndrome. An acute vestibular syndrome is a vestibular symptom that lasts for days up to weeks. The episodic vestibular syndrome is vestibular symptoms that periodically appear. The chronic vestibular syndrome is a vestibular symptom that appears from months to years. Diagnosing vestibular symptoms must be precisely made. The proper termination is the best way to facilitate doctors in communicating with each other. Using this classification is a precise and easy way to detect vestibular etiology. This review is made for clinicians to determine and differentiate the etiology of the vestibular syndrome and gives information in uniforming nomenclature of vestibular symptoms.

Patients with panic disorder often describe dizziness as a disturbing symptom, with more severe episodes reported than in other psychiatric populations. Nineteen patients diagnosed as having a panic disorder were tested for vestibulo-ocular (VOR) abnormalities with the Vestibular Autorotation Test (VAT), a computerized test of the high-frequency (2 to 6 Hz) VOR. The patients were unselected for the presence or absence of balance disorders. Results showed VOR abnormalities, relative to a normal population, in the horizontal and/or vertical VORs of all 19 patients. Vestibulo-ocular reflex asymmetries were commonly present. Because the VAT tested the VOR over a frequency range encountered during common daily activities, the observed abnormalities could result in a perceptually moving visual field (oscillopsia). We hypothesize that the resulting experience of a visual-vestibular disturbance—perhaps in a biologically or psychologically predisposed individual—is catastrophically misinterpreted, leading to more bodily symptoms and anxiety. These could then contribute to more misinterpretation in a positive feedback sense, ultimately leading to a panic attack.

Although the use of vestibular exercises for patients with persistent vertigo and dysequilibrium has received some attention for many years, organized vestibular rehabilitation therapy programs have only recently been introduced. The benefits of such programs are becoming widely accepted. They typically involve a three-pronged approach: habituation exercises designed to facilitate central nervous system compensation by extinguishing pathologic responses to head motion, postural control exercises, and general conditioning activities. This article will describe the programmatic approach to vestibular rehabilitation, emphasizing selection criteria and reviewing results that may be anticipated when this treatment modality is used in a variety of patient populations.

Background. The vestibular system is vital for gaze stability via the vestibulo-ocular reflex, which generates compensatory eye motion in the direction opposite to head motion. Consequently, individuals with peripheral vestibular loss demonstrate impaired gaze stability that reduces functional capacity and quality of life. To facilitate patients’ compensatory strategies, two classes of gaze stabilization exercises are often prescribed: (i) transient (eg, ballistic) and (ii) continuous. However, the relative benefits of these two classes of exercises are not well understood. Objective. To quantify head motion kinematics in patients with vestibular loss while they performed both classes of exercises. Methods. Using inertial measurement units, head movements of 18 vestibular schwannoma patients were measured before and after surgical deafferentation and compared with age-matched controls. Results. We found that the head movement during both classes of exercises paralleled those of natural head movement recorded during daily activities. However, head movement patterns were more informative for continuous than transient exercises in distinguishing patients from healthy controls. Specifically, we observed coupling between kinematic measures in control subjects that was absent in patients for continuous but not transient head motion exercises. In addition, kinematic measures (eg, cycle duration) were predictive of standard clinical measures for continuous but not transient head motion exercises. Conclusions. Our data suggest that performing continuous head motion is a greater motor control challenge than transient head motion in patients with less reliable vestibular feedback during the sub-acute stage of recovery, which may also prove to be a reliable measure of progression in vestibular rehabilitation protocols.

Les informations proprioceptives musculaire et vestibulaire occupent un rôle majeur dans l'organisation des activités posturales et locomotrices. L'exercice musculaire chez l'homme et l'exposition à un environnement hypergravitaire chez le rat ont été utilisés pour moduler ces informations. Nous avons analysé les conséquences de ces modulations sur l'acuité du sens de la position chez l'homme, le comportement postural et locomoteur ainsi que les propriétés des muscles antigravitaires chez l'animal. Chez l'homme l'exercice musculaire améliore la sensibilité kinesthésique. Cette amélioration peut contribuer à expliquer les meilleures performances motrices résultant d'un échauffement musculaire. Par ailleurs, des rats conçus, nés et élevés en hypergravité (2 g) manifestent au passage à 1 g des désordres posturaux (élargissement de la surface d'appui, déficits dans la réaction de retournement) et locomoteurs (hyperactivité et désorientation spatiale, modifications de la cinématique). La sensibilité du système vestibulaire et le fonctionnement musculaire semblent être principalement impliqués dans ces perturbations dont la plupart disparaissent au bout de trois semaines passées en gravité terrestre. Les muscles extenseurs de la cheville présentent chez les mêmes animaux au passage à 1 g des propriétés contractiles et une composition différentes de celles des animaux témoins. Le soléaire et le plantaire développent une force plus importante et accentuent leurs caractéristiques de muscles respectivement lent et rapide. L'absence de normalisation au bout de deux mois passés en gravité terrestre suggère soit une imprégnation irréversible du système neuro-musculaire, soit un ralentissement des processus de plasticité en hypergravité.

Critical elements of early infant motor development can be observed when very young babies spontaneously kick and wave their arms. This initial movement phase progresses through various motor milestones from engaging the inhibition of the primitive reflexes through to rudimentary movements, fundamental motor skills, and finally to engaging in specialised sports activities in the early primary school age years (Gabbard, 2012; Goodway, Ozmun, & Gallahue, 2019). Even though infants have the propensity to naturally move through these rudimentary motor milestones, time spent in awake prone positions is central to achieving to achieving these skills (Ohman, Nilsson, Lagerkvist, & Beckung, 2009). Prone positioning is commonly referred to as tummy time, which has been described as a practice whereby an infant is placed on their stomach during awake play times (Hewitt, Stanley, & Okely, 2017). This tummy time positioning encourages head, neck and arm strength supporting timely rudimentary rolling and crawling skills (Dudek-Shriber & Zelazny, 2007; Jennings, Sarbaugh, & Payne, 2009; Lobo & Galloway, 2012; Majnemer & Snider, 2005), and also reducing the risk of deformational plagiocephaly or flat head syndrome (Kennedy, Majnemer, Farmer, Barr, & Platt, 2009). Researchers have proposed that motor development and motor milestones in infants may be affected or in some cases delayed, following the introduction of sleeping babies on their backs as a result of the SIDS (Sudden Infant Death Syndrome) campaign of the 1990s (Davis, Moon, Sachs, & Ottolini, 1998; Speltz et al., 2010). As a consequence of this campaign the incidence of SIDs declined worldwide in the following years although it was reported that parents tended to avoid placing their infants on their stomach during awake times, subsequently affecting motor milestones, head shape and core strength (Davis et al., 1998; Robertson, 2011). This doctoral research centres on the Baby Activity Chart-Program (BAC-Program) that was devised and created to support families and to provide a variety of fun, tummy time and vestibular focused actions for infants from 6 weeks post birth. Families are encouraged to interact with BAC-Program’s four milestone focused divisions of 34 activities, and culminating when the infant is mobile, feasibly crawling on hands and knees. The doctoral research incorporated the concept and activities within the BAC- Program, and subsequently undertook two separate but inter-linked research studies. Study one involves the evaluation of the BAC-Program through an ‘experts’ response questionnaire’ (ERQ) presented to sixteen experts in the early childhood and the allied health professions. The questionnaire consisted of five sections covering all aspects of the BAC Program’s design, layout, diagrams, text and contents. The Experts were instructed to rate all milestone divisions within the BAC-Program within the questionnaire’s five sections and to also include comments and suggestions according to each expert’s professional expertise. Overall, this first study produced a very positive result with the BAC-Program being effectively recommended by 93% of the experts. Consequently, a BAC-Program/2 (BAC- P/2) was created as the Expert’s recommendations were carefully analysed and those considered significant and theory based to enhance the activities were incorporated into the newly produced infant activity program-edition two. The positive endorsement and results achieved in Study one enabled the newly created BAC-P/2 to be investigated in a further study within this doctoral research. Study two investigated whether an experimental group of twenty nine infants that commenced participation in the BAC-Program/2 at 10 weeks of age, were more advanced in their motor skills (prone, supine, sitting, standing) when compared to a control group of thirty four infants also observed at 7-9 months post birth. The control group had not participated in the BAC-P/2 but were presented with the program at the completion of the testing procedure. The overall results defined that the total percentage mean score on the Alberta Infant Motor Scale (AIMS) of the experimental group was significantly higher (the difference was significant at .023 alpha level) than the control group’s mean score based on all sixty three infant’s AIMS’ motor development scores. The interpretation at a practical level suggests that the participation by parents and carers in the activities within the BAC-P/2 have contributed to the overall differences in the recorded scores when comparing the means between the sample groups using the SPSS independent sample t-test. Study two also examined the differences in overall motor development between groups in relation to time spent daily in tummy time and in vestibular stimulating activities. The experimental group spent greater time daily in both activity categories (tummy time and vestibular) and recorded a higher total percentage mean AIMS score when compared to the control group, however, the differences were not statistically significant. The data revealed that the association between the two study group’s AIMS scores may be influenced by the varying amount of both daily tummy time and daily vestibular time. Interestingly, both study groups reported higher total mean percentage scores in relation to greater amounts of time spent in both tummy time and vestibular activities. The overall conclusion to this study was reinforced by the result that when participating in the BAC-Program/2 from 10 weeks to 7-9 months, involving specifically modified infant movement activities, the twenty nine experimental group infants were significantly advanced in their motor development. There are also recognisable benefits (e.g. improved head control, core strength, response to gravity, spatial and body awareness) for infants to spend significant time in tummy and vestibular focused movements in regard to achieving their motor milestones.

The thesis deals with the issues of balance disorders in patients after vestibular schwannoma surgery. The aim of this thesis is to evaluate the effect of targeted rehabilitation with biofeedback on balance disorders and subjective visual vertical compensation. During the period of one year, a group of 20 vestibular schwannoma patients were examined and treated in University Hospital Motol. The compensation of vestbuloocular refex was assessed by a tilt of subjective visual vertical. The level of vestibulospinal compensation was determined according to score of the Activities-Specific Balance Confidence Scale. Patients were examined before the surgery, after the surgery and after the rehabilitation. The Homebalance system, developed by Support center for application outputs and spin-off companies at the 1st Faculty of Medicine, Charles University in Prague, branch office in Kladno, was used for the therapy with visual biofeedback. Another aim of this thesis was to monitor the effect of vestibular prehabituation with ototoxic gentamicin application two months before surgery. The statistical analysis of data proved in the case of subjective visual vertical tilt a significant increase of deviation after surgery and a decrease after rehabilitation. According to the ABC questionnaire the confidence of...

Vestibular rehabilitation (VR) is a therapeutic approach prepared specifically for each individual who has a vestibular and balance disorder. VR helps in the treatment of unilateral or bilateral vestibular hypofunction and vestibular problems such as labyrinthitis and vestibular neuronitis. Individuals who have inner ear problems which have not been solved for a long time or have received medical treatment benefit from VR. In addition, VR helps to alleviate the complaints of individuals who have undergone surgery due to vestibular problems. With the VR program, regulative activities are carried out to decrease the duration, intensity, and frequency of vertigo; the symptoms of vertigo; increase independency in daily life activities; and to make it possible for patients to deal with the feelings of dizziness, imbalance, and anxiety, in addition to training patients about this issue and regulating the general conditions. The aim is to increase the life quality of patients.

The vestibular system is responsible for sensing the velocity and acceleration of angular and linear movements of the head and sensitivity to gravity in maintaining balance with its peripheral and central structures. It performs this function through vestibular reflexes. When peripheral vestibular diseases occur unilaterally or bilaterally, the functions of vestibular reflexes are affected, resulting in deterioration in eye movements compatible with head movements and anti-gravity muscle activity coordination, which ensures upright posture against gravity. Dizziness and/or imbalance persist in patients in whom the central compensation process cannot be completed, resulting in restrictions in the patient’s independent movements, daily activities, and quality of life. In the middle and long term, these restrictions cause sedentary life, fear of falling, loss of general condition, emotional problems, and social isolation. In patients diagnosed with unilateral peripheral vestibular disease, vestibular rehabilitation methods based on exercise and living environment arrangements are used as valid and reliable methods to support central compensation mechanisms and to eliminate movement restrictions. Along with conventional exercises, virtual reality-based vestibular rehabilitation systems on stable or unstable platforms are also used for this purpose. In this chapter, the essential principles of conventional and virtual reality-based vestibular rehabilitation methods take place.

In being seated, standing, and walking, many uncontrollable factors contribute to the degradation of our balance system. The maintenance of balance involves many essential sensory (visual, vestibular, and somatosensory) and motor processes. Each sensory input provides unique internal and external reference frame information to the central nervous system (CNS). The CNS interprets the sensory information, from which preplanned and/or preventative (feedforward controls) and corrective (feedback controls) actions can be taken and conflicting sensory information can be mediated (Peterka, 2002). In the absence of a sensory input, balance can still be maintained; however, the compensatory actions become larger and different balance strategies may be employed. Serious problems facing older adults and many people with neurological disorders (e.g., stroke, traumatic head injuries, incomplete spinal cord injuries, Parkinson’s, multiple sclerosis, diabetic peripheral neuropathy, and osteoarthritis) are balance impairment, mobility restriction, and falling (Gill et al., 2001; Harris, Eng, Marigold, Tokuno, & Louis, 2005). In these cases, even small disturbances may result in a fall and injuries are very likely to occur. This increased risk of falling combined with mobility limitations precipitates patient dependency in instrumental and basic activities of daily living; in turn, this results in reduced levels of physical activity.

The otoliths of the vestibular system are seen as the primary gravitational sensors and are responsible for a compensatory eye torsion called the ocular counter-roll (OCR). The OCR ensures gaze stabilization and is sensitive to a lateral head roll with respect to gravity and the Gravito-Inertial Acceleration (GIA) vector during e.g., centrifugation. This otolith-mediated reflex will make sure you will still be able to maintain gaze stabilization and postural stability when making sharp turns during locomotion. To measure the effect of prolonged spaceflight on the otoliths, we measured the OCR induced by off-axis centrifugation in a group of 27 cosmonauts before and after their 6-month space mission to the International Space Station (ISS). We observed a significant decrease in OCR early post-flight, with first- time flyers being more strongly affected compared to frequent or experienced flyers. Our results strongly suggest that experienced space crew have acquired the ability to adapt faster after G-transitions and should therefore be sent for more challenging space missions, e.g., Moon or Mars, because they are noticeably less affected by microgravity regarding their vestibular system.