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Fitze DC, Mast FW, Ertl M. Human vestibular perceptual thresholds - A systematic review of passive motion perception. Gait Posture 2024; 107:83-95. [PMID: 37778297 DOI: 10.1016/j.gaitpost.2023.09.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 09/12/2023] [Accepted: 09/19/2023] [Indexed: 10/03/2023]
Abstract
BACKGROUND The vestibular system detects head accelerations within 6 degrees of freedom. How well this is accomplished is described by vestibular perceptual thresholds. They are a measure of perceptual performance based on the conscious evaluation of sensory information. This review provides an integrative synthesis of the vestibular perceptual thresholds reported in the literature. The focus lies on the estimation of thresholds in healthy participants, used devices and stimulus profiles. The dependence of these thresholds on the participants clinical status and age is also reviewed. Furthermore, thresholds from primate studies are discussed. RESULTS Thresholds have been measured for frequencies ranging from 0.05 to 5 Hz. They decrease with increasing frequency for five of the six main degrees of freedom (inter-aural, head-vertical, naso-occipital, yaw, pitch). No consistent pattern is evident for roll rotations. For a frequency range beyond 5 Hz, a U-shaped relationship is suggested by a qualitative comparison to primate data. Where enough data is available, increasing thresholds with age and higher thresholds in patients compared to healthy controls can be observed. No effects related to gender or handedness are reported. SIGNIFICANCE Vestibular thresholds are essential for next generation screening tools in the clinical domain, for the assessment of athletic performance, and workplace safety alike. Knowledge about vestibular perceptual thresholds contributes to basic and applied research in fields such as perception, cognition, learning, and healthy aging. This review provides normative values for vestibular thresholds. Gaps in current knowledge are highlighted and attention is drawn to specific issues for improving the inter-study comparability in the future.
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Affiliation(s)
- Daniel C Fitze
- Department of Psychology, University of Bern, Fabrikstrasse 8, 3012, Bern, Switzerland.
| | - Fred W Mast
- Department of Psychology, University of Bern, Fabrikstrasse 8, 3012, Bern, Switzerland.
| | - Matthias Ertl
- Department of Psychology, University of Bern, Fabrikstrasse 8, 3012, Bern, Switzerland.
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Gonzalez ELC, King SA, Karmali F. Your Vestibular Thresholds May Be Lower Than You Think: Cognitive Biases in Vestibular Psychophysics. Am J Audiol 2023; 32:730-738. [PMID: 37084775 PMCID: PMC10721247 DOI: 10.1044/2023_aja-22-00186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 12/23/2022] [Accepted: 02/08/2023] [Indexed: 04/23/2023] Open
Abstract
PURPOSE Recently, there has been a surge of interest in measuring vestibular perceptual thresholds, which quantify the smallest motion that a subject can reliably perceive, to study physiology and pathophysiology. These thresholds are sensitive to age, pathology, and postural performance. Threshold tasks require decisions to be made in the presence of uncertainty. Since humans often rely on past information when making decisions in the presence of uncertainty, we hypothesized that (a) perceptual responses are affected by their preceding trial; (b) perceptual responses tend to be biased opposite of the "preceding response" because of cognitive biases but are not biased by the "preceding stimulus"; and (c) when fits do not account for this cognitive bias, thresholds are overestimated. To our knowledge, these hypotheses are unaddressed in vestibular and direction-recognition tasks. CONCLUSIONS Results in normal subjects supported each hypothesis. Subjects tended to respond opposite of their preceding response (not the preceding stimulus), indicating a cognitive bias, and this caused an overestimation of thresholds. Using an enhanced model (MATLAB code provided) that considered these effects, average thresholds were lower (5.5% for yaw, 7.1% for interaural). Since the results indicate that the magnitude of cognitive bias varies across subjects, this enhanced model can reduce measurement variability and potentially improve the efficiency of data collection.
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Affiliation(s)
- Elena Lopez-Contreras Gonzalez
- Jenks Vestibular Physiology Laboratory, Massachusetts Eye and Ear, Boston
- Department of Otolaryngology–Head and Neck Surgery, Harvard Medical School, Boston, MA
| | - Susan A. King
- Jenks Vestibular Physiology Laboratory, Massachusetts Eye and Ear, Boston
| | - Faisal Karmali
- Jenks Vestibular Physiology Laboratory, Massachusetts Eye and Ear, Boston
- Department of Otolaryngology–Head and Neck Surgery, Harvard Medical School, Boston, MA
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3
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Keriven Serpollet D, Hartnagel D, James Y, Buffat S, Vayatis N, Bargiotas I, Vidal P. Tilt perception is different in the pitch and roll planes in human. Physiol Rep 2023; 11:e15374. [PMID: 36780905 PMCID: PMC9925277 DOI: 10.14814/phy2.15374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 04/21/2022] [Accepted: 05/27/2022] [Indexed: 02/15/2023] Open
Abstract
Neurophysiological tests probing the vestibulo-ocular, colic and spinal pathways are the gold standard to evaluate the vestibular system in clinics. In contrast, vestibular perception is rarely tested despite its potential usefulness in professional training and for the longitudinal follow-up of professionals dealing with complex man-machine interfaces, such as aircraft pilots. This is explored here using a helicopter flight simulator to probe the vestibular perception of pilots. The vestibular perception of nine professional helicopter pilots was tested using a full flight helicopter simulator. The cabin was tilted six times in roll and six times in pitch (-15°, -10°, -5°, 5°, 10° and 15°) while the pilots had no visual cue. The velocities of the outbound displacement of the cabin were kept below the threshold of the semicircular canal perception. After the completion of each movement, the pilots were asked to put the cabin back in the horizontal plane (still without visual cues). The order of the 12 trials was randomized with two additional control trials where the cabin stayed in the horizontal plane but rotated in yaw (-10° and +10°). Pilots were significantly more precise in roll (average error in roll: 1.15 ± 0.67°) than in pitch (average error in pitch: 2.89 ± 1.06°) (Wilcoxon signed-rank test: p < 0.01). However, we did not find a significant difference either between left and right roll tilts (p = 0.51) or between forward and backward pitch tilts (p = 0.59). Furthermore, we found that the accuracies were significantly biased with respect to the initial tilt. The greater the initial tilt was, the less precise the pilots were, although maintaining the direction of the tilt, meaning that the error can be expressed as a vestibular error gain in the ability to perceive the modification in the orientation. This significant result was found in both roll (Friedman test: p < 0.01) and pitch (p < 0.001). However, the pitch trend error was more prominent (gain = 0.77 vs gain = 0.93) than roll. This study is a first step in the determination of the perceptive-motor profile of pilots, which could be of major use for their training and their longitudinal follow-up. A similar protocol may also be useful in clinics to monitor the aging process of the otolith system with a simplified testing device.
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Affiliation(s)
- Dimitri Keriven Serpollet
- Training & Simulation, Thales AVS France SASOsnyFrance
- Centre Borelli, Université de Paris, ENS Paris‐Saclay, CNRS, SSAParisFrance
| | - David Hartnagel
- Département Neurosciences et Sciences CognitivesInstitut de Recherche Biomédicale des ArméesBrétigny‐sur‐OrgeFrance
| | - Yannick James
- Training & Simulation, Thales AVS France SASOsnyFrance
| | - Stéphane Buffat
- Laboratoire d'Accidentologie de Biomécanique et du comportement des conducteursGIE Renault‐PSA GroupesNanterreFrance
| | - Nicolas Vayatis
- Centre Borelli, Université de Paris, ENS Paris‐Saclay, CNRS, SSAParisFrance
| | - Ioannis Bargiotas
- Centre Borelli, Université de Paris, ENS Paris‐Saclay, CNRS, SSAParisFrance
| | - Pierre‐Paul Vidal
- Centre Borelli, Université de Paris, ENS Paris‐Saclay, CNRS, SSAParisFrance
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Bretl KN, Clark TK. Predicting individual acclimation to the cross-coupled illusion for artificial gravity. J Vestib Res 2021; 32:305-316. [PMID: 34806642 DOI: 10.3233/ves-210019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND The cross-coupled (CC) illusion and associated motion sickness limits the tolerability of fast-spin-rate centrifugation for artificial gravity implementation. Humans acclimate to the CC illusion through repeated exposure; however, substantial inter-individual differences in acclimation exist, which remain poorly understood. To address this, we investigated several potential predictors of individual acclimation to the CC illusion. METHODS Eleven subjects were exposed to the CC illusion for up to 50 25-minute acclimation sessions. The metric of acclimation rate was calculated as the slope of each subject's linear increase in spin rate across sessions. As potential predictors of acclimation rate, we gathered age, gender, demographics, and activity history, and measured subjects' vestibular perceptual thresholds in the yaw, pitch, and roll rotation axes. RESULTS We found a significant, negative correlation (p = 0.025) between subjects' acclimation rate and roll threshold, suggesting lower thresholds yielded faster acclimation. Additionally, a leave-one-out cross-validation analysis indicated that roll thresholds are predictive of acclimation rates. Correlations between acclimation and other measures were not found but were difficult to assess within our sample. CONCLUSIONS The ability to predict individual differences in CC illusion acclimation rate using roll thresholds is critical to optimizing acclimation training, improving the feasibility of fast-rotation, short-radius centrifugation for artificial gravity.
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Affiliation(s)
- Kathrine N Bretl
- University of Colorado Boulder, 3775 Discovery Drive, Boulder, CO, United States
| | - Torin K Clark
- University of Colorado Boulder, 3775 Discovery Drive, Boulder, CO, United States
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5
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Diaz-Artiles A, Karmali F. Vestibular Precision at the Level of Perception, Eye Movements, Posture, and Neurons. Neuroscience 2021; 468:282-320. [PMID: 34087393 PMCID: PMC9188304 DOI: 10.1016/j.neuroscience.2021.05.028] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 05/20/2021] [Accepted: 05/24/2021] [Indexed: 11/18/2022]
Abstract
Precision and accuracy are two fundamental properties of any system, including the nervous system. Reduced precision (i.e., imprecision) results from the presence of neural noise at each level of sensory, motor, and perceptual processing. This review has three objectives: (1) to show the importance of studying vestibular precision, and specifically that studying accuracy without studying precision ignores fundamental aspects of the vestibular system; (2) to synthesize key hypotheses about precision in vestibular perception, the vestibulo-ocular reflex, posture, and neurons; and (3) to show that groups of studies that are thoughts to be distinct (e.g., perceptual thresholds, subjective visual vertical variability, neuronal variability) are actually "two sides of the same coin" - because the methods used allow results to be related to the standard deviation of a Gaussian distribution describing the underlying neural noise. Vestibular precision varies with age, stimulus amplitude, stimulus frequency, body orientation, motion direction, pathology, medication, and electrical/mechanical vestibular stimulation, but does not vary with sex. The brain optimizes precision during integration of vestibular cues with visual, auditory, and/or somatosensory cues. Since a common concern with precision metrics is time required for testing, we describe approaches to optimize data collection and provide evidence that fatigue and session effects are minimal. Finally, we summarize how precision is an individual trait that is correlated with clinical outcomes in patients as well as with performance in functional tasks like balance. These findings highlight the importance of studying vestibular precision and accuracy, and that knowledge gaps remain.
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Affiliation(s)
- Ana Diaz-Artiles
- Bioastronautics and Human Performance Laboratory, Department of Aerospace Engineering, Department of Health and Kinesiology, Texas A&M University, College Station, TX 77843-3141, USA. https://bhp.engr.tamu.edu
| | - Faisal Karmali
- Jenks Vestibular Physiology Laboratory, Massachusetts Eye and Ear Infirmary, Boston, MA, USA; Department of Otolaryngology - Head and Neck Surgery, Harvard Medical School, Boston MA, USA.
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6
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Karmali F, Goodworth AD, Valko Y, Leeder T, Peterka RJ, Merfeld DM. The role of vestibular cues in postural sway. J Neurophysiol 2021; 125:672-686. [PMID: 33502934 DOI: 10.1152/jn.00168.2020] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Controlling posture requires continuous sensory feedback about body motion and orientation, including from the vestibular organs. Little is known about the role of tilt vs. translation vs. rotation vestibular cues. We examined whether intersubject differences in vestibular function were correlated with intersubject differences in postural control. Vestibular function was assayed using vestibular direction-recognition perceptual thresholds, which determine the smallest motion that can be reliably perceived by a subject seated on a motorized platform in the dark. In study A, we measured thresholds for lateral translation, vertical translation, yaw rotation, and head-centered roll tilts. In study B, we measured thresholds for roll, pitch, and left anterior-right posterior and right anterior-left posterior tilts. Center-of-pressure (CoP) sway was measured in sensory organization tests (study A) and Romberg tests (study B). We found a strong positive relationship between CoP sway and lateral translation thresholds but not CoP sway and other thresholds. This finding suggests that the vestibular encoding of lateral translation may contribute substantially to balance control. Since thresholds assay sensory noise, our results support the hypothesis that vestibular noise contributes to spontaneous postural sway. Specifically, we found that lateral translation thresholds explained more of the variation in postural sway in postural test conditions with altered proprioceptive cues (vs. a solid surface), consistent with postural sway being more dependent on vestibular noise when the vestibular contribution to balance is higher. These results have potential implications for vestibular implants, balance prostheses, and physical therapy exercises.NEW & NOTEWORTHY Vestibular feedback is important for postural control, but little is known about the role of tilt cues vs. translation cues vs. rotation cues. We studied healthy human subjects with no known vestibular pathology or symptoms. Our findings showed that vestibular encoding of lateral translation correlated with medial-lateral postural sway, consistent with lateral translation cues contributing to balance control. This adds support to the hypothesis that vestibular noise contributes to spontaneous postural sway.
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Affiliation(s)
- Faisal Karmali
- Department of Otolaryngology-Head and Neck Surgery, Harvard Medical School, Boston, Massachusetts.,Jenks Vestibular Physiology Laboratory, Massachusetts Eye and Ear, Boston, Massachusetts
| | - Adam D Goodworth
- Kinesiology Department, Westmont College, Santa Barbara, California
| | - Yulia Valko
- Departments of Ophthalmology and Neurology, University Hospital Zurich, University of Zurich, Switzerland
| | - Tania Leeder
- Jenks Vestibular Physiology Laboratory, Massachusetts Eye and Ear, Boston, Massachusetts
| | - Robert J Peterka
- Department of Neurology, Oregon Health and Science University, Portland, Oregon.,National Center for Rehabilitative Auditory Research, Veterans Affairs Portland Health Care System, Portland, Oregon
| | - Daniel M Merfeld
- Department of Otolaryngology - Head and Neck Surgery, The Ohio State University, Columbus, Ohio
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von Laßberg C, Campos JL, Beykirch KA. Long term measures of vestibulo-ocular reflex function in high level male gymnasts and its possible role during context specific rotational tasks. PLoS One 2020; 15:e0243752. [PMID: 33315913 PMCID: PMC7735588 DOI: 10.1371/journal.pone.0243752] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 11/25/2020] [Indexed: 11/18/2022] Open
Abstract
In a prior publication, we described a previously unknown eye movement phenomenon during the execution of actively performed multiaxial rotations in high level gymnasts. This phenomenon was consistently observed during the phase of fast free flight rotations and was marked by a prolonged and complete suppression of nystagmus and gaze stabilizing “environment referenced eye movements” (EREM; such as the vestibulo-ocular reflex, optokinetic reflex, smooth pursuit and others). Instead, these eye movements were coupled with intersegmental body movements. We have therefore called it “spinal motor-coupled eye movements” (SCEM) and have interpreted the phenomenon to likely be caused by anti-compensatory functions of more proprioceptive mediated reflexes and perhaps other mechanisms (e.g., top-down regulation as part of a motor plan) to effectively cope with a new-orientation in space, undisturbed by EREM functions. In the phase before landing, the phenomenon was replaced again by the known gaze-stabilizing EREM functions. The present study specifically evaluated long-term measures of vestibulo-ocular reflex functions (VOR) in high level gymnasts and controls during both passively driven monoaxial rotations and context-specific multiaxial somersault simulations in a vestibular lab. This approach provided further insights into the possible roles of adaptive or mental influences concerning the VOR function and how they are associated with the described phenomenon of SCEM. Results showed high inter-individual variability of VOR function in both gymnasts and controls, but no systematic adaptation of the VOR in gymnasts, neither compared to controls nor over a period of three years. This might generally support the hypothesis that the phenomenon of SCEM might indeed be driven more by proprioceptively mediated and situationally dominant eye movement functions than by adaptative processes of the VOR.
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Affiliation(s)
- Christoph von Laßberg
- Department Sports Medicine, Medical Clinic, University of Tübingen, Tübingen, Germany
- * E-mail:
| | - Jennifer L. Campos
- Toronto Rehabilitation Institute–University Health Network, Toronto, Canada
- Department of Psychology, University of Toronto, Toronto, Canada
| | - Karl A. Beykirch
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany
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8
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Human vestibular perceptual thresholds for pitch tilt are slightly worse than for roll tilt across a range of frequencies. Exp Brain Res 2020; 238:1499-1509. [DOI: 10.1007/s00221-020-05830-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 05/08/2020] [Indexed: 01/18/2023]
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9
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Allum JHJ, Rust HM, Honegger F. Functional Testing of Vestibulo-Spinal Contributions to Balance Control: Insights From Tracking Improvement Following Acute Bilateral Peripheral Vestibular Loss. Front Neurol 2019; 10:550. [PMID: 31191439 PMCID: PMC6546919 DOI: 10.3389/fneur.2019.00550] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 05/07/2019] [Indexed: 11/13/2022] Open
Abstract
Background: A battery of stance and gait tasks can be used to quantify functional deficits and track improvement in balance control following peripheral vestibular loss. An improvement could be due to at least 3 processes: partial peripheral recovery of sensory responses eliciting canal or otolith driven vestibular reflexes; central compensation of vestibular reflex gains, including substitution of intact otolith responses for pathological canal responses; or sensory substitution of visual and proprioceptive inputs for vestibular contributions to balance control. Results: We describe the presumed action of all 3 processes observed for a case of sudden incapacitating acute bilateral peripheral loss probably due to vestibular neuritis. Otolith responses were largely unaffected. However, pathological decreases in all canal-driven vestibular ocular reflex (VOR) gains were observed. After 3 months of vestibular rehabilitation, balance control was normal but VOR gains remained low. Conclusions: This case illustrates the difficulty in predicting balance control improvements from tests of the 10 vestibular end organs and emphasizes the need to test balance control function directly in order to determine if balance control has improved and is normal again despite remaining vestibular sensory deficits. This case also illustrates that the presence of residual otolithic function may be crucial for balance control improvement in cases of bilateral vestibular hypofunction.
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Affiliation(s)
- John H. J. Allum
- Division of Audiology and Neurootology, Department of Otorhinolaryngology (ORL), University Hospital Basel, Basel, Switzerland
| | - Heiko Mario Rust
- Department of Neurology, University of Basel Hospital, Basel, Switzerland
- Division of Brain Sciences, Academic Department of Neuro-Otology, Charing Cross Hospital, Imperial College, London, United Kingdom
| | - Flurin Honegger
- Division of Audiology and Neurootology, Department of Otorhinolaryngology (ORL), University Hospital Basel, Basel, Switzerland
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10
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Paillard T. Plasticity of the postural function to sport and/or motor experience. Neurosci Biobehav Rev 2017; 72:129-152. [DOI: 10.1016/j.neubiorev.2016.11.015] [Citation(s) in RCA: 103] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 10/27/2016] [Accepted: 11/15/2016] [Indexed: 11/27/2022]
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11
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Maitre J, Paillard T. Postural Effects of Vestibular Manipulation Depend on the Physical Activity Status. PLoS One 2016; 11:e0162966. [PMID: 27627441 PMCID: PMC5023127 DOI: 10.1371/journal.pone.0162966] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Accepted: 08/31/2016] [Indexed: 12/02/2022] Open
Abstract
The purpose of this study was to compare the effects of galvanic vestibular stimulation (GVS) on postural control for participants of different physical activity status (i.e. active and non-active). Two groups of participants were recruited: one group of participants who regularly practised sports activities (active group, n = 17), and one group of participants who did not practise physical and/or sports activities (non-active group, n = 17). They were compared in a reference condition (i.e bipedal stance with eyes open) and four vestibular manipulation condition (i.e. GVS at 0.5 mA and 3 mA, in accordance with two designs) lasting 20 seconds. The centre of foot pressure displacement velocities were compared between the two groups. The main results indicate that the regular practice of sports activities counteracts postural control disruption caused by GVS. The active group demonstrated better postural control than the non-active group when subjected to higher vestibular manipulation. The active group may have developed their ability to reduce the influence of inaccurate vestibular signals. The active participants could identify the relevant sensory input, thought a better central integration, which enables them to switch faster between sensory inputs.
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Affiliation(s)
- Julien Maitre
- Laboratoire Mouvement, Equilibre, Performance et Santé, EA 4445, Université de Pau et des Pays de l’Adour, Département STAPS, Tarbes, France
| | - Thierry Paillard
- Laboratoire Mouvement, Equilibre, Performance et Santé, EA 4445, Université de Pau et des Pays de l’Adour, Département STAPS, Tarbes, France
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12
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Karmali F, Chaudhuri SE, Yi Y, Merfeld DM. Determining thresholds using adaptive procedures and psychometric fits: evaluating efficiency using theory, simulations, and human experiments. Exp Brain Res 2015; 234:773-89. [PMID: 26645306 DOI: 10.1007/s00221-015-4501-8] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 11/12/2015] [Indexed: 11/29/2022]
Abstract
When measuring thresholds, careful selection of stimulus amplitude can increase efficiency by increasing the precision of psychometric fit parameters (e.g., decreasing the fit parameter error bars). To find efficient adaptive algorithms for psychometric threshold ("sigma") estimation, we combined analytic approaches, Monte Carlo simulations, and human experiments for a one-interval, binary forced-choice, direction-recognition task. To our knowledge, this is the first time analytic results have been combined and compared with either simulation or human results. Human performance was consistent with theory and not significantly different from simulation predictions. Our analytic approach provides a bound on efficiency, which we compared against the efficiency of standard staircase algorithms, a modified staircase algorithm with asymmetric step sizes, and a maximum likelihood estimation (MLE) procedure. Simulation results suggest that optimal efficiency at determining threshold is provided by the MLE procedure targeting a fraction correct level of 0.92, an asymmetric 4-down, 1-up staircase targeting between 0.86 and 0.92 or a standard 6-down, 1-up staircase. Psychometric test efficiency, computed by comparing simulation and analytic results, was between 41 and 58% for 50 trials for these three algorithms, reaching up to 84% for 200 trials. These approaches were 13-21% more efficient than the commonly used 3-down, 1-up symmetric staircase. We also applied recent advances to reduce accuracy errors using a bias-reduced fitting approach. Taken together, the results lend confidence that the assumptions underlying each approach are reasonable and that human threshold forced-choice decision making is modeled well by detection theory models and mimics simulations based on detection theory models.
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Affiliation(s)
- Faisal Karmali
- Jenks Vestibular Physiology Lab, Massachusetts Eye and Ear Infirmary, 243 Charles St., Boston, MA, 02114, USA. .,Department of Otology and Laryngology, Harvard Medical School, Boston, MA, USA.
| | - Shomesh E Chaudhuri
- Jenks Vestibular Physiology Lab, Massachusetts Eye and Ear Infirmary, 243 Charles St., Boston, MA, 02114, USA.,Department of Electrical Engineering and Computer Science, MIT, Cambridge, MA, USA
| | - Yongwoo Yi
- Jenks Vestibular Physiology Lab, Massachusetts Eye and Ear Infirmary, 243 Charles St., Boston, MA, 02114, USA.,Department of Otology and Laryngology, Harvard Medical School, Boston, MA, USA
| | - Daniel M Merfeld
- Jenks Vestibular Physiology Lab, Massachusetts Eye and Ear Infirmary, 243 Charles St., Boston, MA, 02114, USA.,Department of Otology and Laryngology, Harvard Medical School, Boston, MA, USA
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13
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Moser I, Grabherr L, Hartmann M, Mast FW. Self-motion direction discrimination in the visually impaired. Exp Brain Res 2015. [PMID: 26223579 DOI: 10.1007/s00221-015-4389-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Despite the close interrelation between vestibular and visual processing (e.g., vestibulo-ocular reflex), surprisingly little is known about vestibular function in visually impaired people. In this study, we investigated thresholds of passive whole-body motion discrimination (leftward vs. rightward) in nine visually impaired participants and nine age-matched sighted controls. Participants were rotated in yaw, tilted in roll, and translated along the interaural axis at two different frequencies (0.33 and 2 Hz) by means of a motion platform. Superior performance of visually impaired participants was found in the 0.33 Hz roll tilt condition. No differences were observed in the other motion conditions. Roll tilts stimulate the semicircular canals and otoliths simultaneously. The results could thus reflect a specific improvement in canal-otolith integration in the visually impaired and are consistent with the compensatory hypothesis, which implies that the visually impaired are able to compensate the absence of visual input.
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Affiliation(s)
- Ivan Moser
- Department of Psychology, University of Bern, Fabrikstrasse 8, Bern, 3012, Switzerland. .,Center for Cognition, Learning and Memory, University of Bern, Fabrikstrasse 8, Bern, 3012, Switzerland.
| | - Luzia Grabherr
- Sansom Institute for Health Research, University of South Australia, GPO Box 2471, Adelaide, SA, 5001, Australia
| | - Matthias Hartmann
- Department of Psychology, University of Bern, Fabrikstrasse 8, Bern, 3012, Switzerland.,Center for Cognition, Learning and Memory, University of Bern, Fabrikstrasse 8, Bern, 3012, Switzerland
| | - Fred W Mast
- Department of Psychology, University of Bern, Fabrikstrasse 8, Bern, 3012, Switzerland.,Center for Cognition, Learning and Memory, University of Bern, Fabrikstrasse 8, Bern, 3012, Switzerland
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