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Subjective visual vertical imprecision during lateral head tilt in patients with chronic dizziness. Exp Brain Res 2021; 240:199-206. [PMID: 34687330 DOI: 10.1007/s00221-021-06247-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Accepted: 10/14/2021] [Indexed: 10/20/2022]
Abstract
Most prior studies of the subjective visual vertical (SVV) focus on inaccuracy of subjects' SVV responses with the head in an upright position. Here we investigated SVV imprecision during lateral head tilt in patients with chronic dizziness compared to healthy controls. Forty-five dizzy patients and 45 healthy controls underwent SVV testing wearing virtual reality (VR) goggles, sitting upright (0°) and during head tilt in the roll plane (± 30°). Ten trials were completed in each of three static head positions. The SVV inaccuracy and SVV imprecision were analyzed and compared between groups, along with systematic errors during head tilt, i.e., A-effect and E-effect (E-effect is a typical SVV response during head tilts of ± 30°). The SVV imprecision was found to be affected by head position (upright/right head tilt/left head tilt, p < 0.001) and underlying dizziness (dizzy patients/healthy controls, p = 0.005). The SVV imprecision during left head tilt was greater in dizzy patients compared to healthy controls (p = 0.04). With right head tilt, there was a trend towards greater SVV imprecision in dizzy patients (p = 0.08). Dizzy patients were more likely to have bilateral (6.7%) or unilateral (22.2%) A-effect during lateral head tilt than healthy controls (bilateral (0%) or unilateral (6.7%) A-effect, p < 0.01). Greater SVV imprecision in chronically dizzy patients during head tilts may be attributable to increased noise of vestibular sensory afferents or disturbances of multisensory integration. Our findings suggest that SVV imprecision may be a useful clinical parameter of underlying dizziness measurable with bedside SVV testing in VR.
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Pascucci Sande de Souza LA, Ferreira LR, Silva Bitencourt AC, Bazan R, Luvizutto GJ. Visual and haptic verticality misperception and trunk control within 72 h after stroke. J Bodyw Mov Ther 2021; 27:676-681. [PMID: 34391306 DOI: 10.1016/j.jbmt.2021.05.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Revised: 03/29/2021] [Accepted: 05/07/2021] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Stroke patients often exhibit an altered perception of verticality, but there are no studies evaluating verticality perception in the first 72 h after stroke and its relationship with trunk control. Therefore, this study aimed to analyze visual and haptic verticality in the acute phase of stroke. METHODS This was a cross-sectional study conducted with two groups: (a) 13 individuals with stroke and (b) 12 healthy participants. We assessed verticality via the subjective visual vertical (SVV) and the subjective haptic vertical (SHV); and we measured trunk control with the Trunk Impairment Scale (TIS). We performed t-tests to compare the SVV and SHV between groups. Pearson correlation was performed between verticality tests with National Institutes of Health Stroke Scale (NIHSS) and the TIS. RESULTS Participants with recent stroke presented higher true and absolute SVV deviation values than did the control group. There was significant negative correlation between absolute (r = -0.57; p = 0.02) and true SVV (r = -0.54; p = 0.01) with TIS scores There was also significant positive correlation between absolute (r = 0.63; p = 0.009) and true SVV (r = 0.61; p = 0.003) with NIHSS. A significant negative correlation between NIHSS and TIS scores also was found (r = -0.80; p = 0.005). CONCLUSION Individuals with acute stroke presented larger variability in their perceptions of visual verticality than did healthy controls, and verticality perceptions were positively correlated with trunk impairment.
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Affiliation(s)
| | - Luana Ribeiro Ferreira
- Master's Program in Physical Therapy, Universidade Federal do Triângulo Mineiro (UFTM), Uberaba, Minas Gerais, Brazil
| | - Ana Carolina Silva Bitencourt
- Master's Program in Physical Therapy, Universidade Federal do Triângulo Mineiro (UFTM), Uberaba, Minas Gerais, Brazil
| | - Rodrigo Bazan
- Department of Neurology, Botucatu Medical School (UNESP), Botucatu, São Paulo, Brazil
| | - Gustavo José Luvizutto
- Department of Applied Physical Therapy, Universidade Federal do Triângulo Mineiro (UFTM), Uberaba, Minas Gerais, Brazil.
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Nakamura J, Shiozaki T, Tsujimoto N, Ikuno K, Okada Y, Shomoto K. Role of somatosensory and/or vestibular sensory information in subjective postural vertical in healthy adults. Neurosci Lett 2020; 714:134598. [DOI: 10.1016/j.neulet.2019.134598] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 10/10/2019] [Accepted: 10/28/2019] [Indexed: 10/25/2022]
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Dupuy EG, Leconte P, Vlamynck E, Sultan A, Chesneau C, Denise P, Besnard S, Bienvenu B, Decker LM. Ehlers-Danlos Syndrome, Hypermobility Type: Impact of Somatosensory Orthoses on Postural Control (A Pilot Study). Front Hum Neurosci 2017. [PMID: 28642694 PMCID: PMC5462950 DOI: 10.3389/fnhum.2017.00283] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Elhers-Danlos syndrome (EDS) is the clinical manifestation of connective tissue disorders, and comprises several clinical forms with no specific symptoms and selective medical examinations which result in a delay in diagnosis of about 10 years. The EDS hypermobility type (hEDS) is characterized by generalized joint hypermobility, variable skin hyperextensibility and impaired proprioception. Since somatosensory processing and multisensory integration are crucial for both perception and action, we put forth the hypothesis that somatosensory deficits in hEDS patients may lead, among other clinical symptoms, to misperception of verticality and postural instability. Therefore, the purpose of this study was twofold: (i) to assess the impact of somatosensory deficit on subjective visual vertical (SVV) and postural stability; and (ii) to quantify the effect of wearing somatosensory orthoses (i.e., compressive garments and insoles) on postural stability. Six hEDS patients and six age- and gender-matched controls underwent a SVV (sitting, standing, lying on the right side) evaluation and a postural control evaluation on a force platform (Synapsys), with or without visual information (eyes open (EO)/eyes closed (EC)). These two latter conditions performed either without orthoses, or with compression garments (CG), or insoles, or both. Results showed that patients did not exhibit a substantial perceived tilt of the visual vertical in the direction of the body tilt (Aubert effect) as did the control subjects. Interestingly, such differential effects were only apparent when the rod was initially positioned to the left of the vertical axis (opposite the longitudinal body axis). In addition, patients showed greater postural instability (sway area) than the controls. The removal of vision exacerbated this instability, especially in the mediolateral (ML) direction. The wearing of orthoses improved postural stability, especially in the eyes-closed condition, with a particularly marked effect in the anteroposterior (AP) direction. Hence, this study suggests that hEDS is associated with changes in the relative contributions of somatosensory and vestibular inputs to verticality perception. Moreover, postural control impairment was offset, at least partially, by wearing somatosensory orthoses.
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Affiliation(s)
- Emma G Dupuy
- COMETE, INSERM, UNICAEN, Normandie UniversitéCaen, France
| | | | | | - Audrey Sultan
- COMETE, INSERM, UNICAEN, Normandie UniversitéCaen, France.,Department of Internal Medicine, University Hospital Center of Caen, UNICAEN, Normandie UniversitéCaen, France
| | | | - Pierre Denise
- COMETE, INSERM, UNICAEN, Normandie UniversitéCaen, France
| | | | - Boris Bienvenu
- COMETE, INSERM, UNICAEN, Normandie UniversitéCaen, France.,Department of Internal Medicine, University Hospital Center of Caen, UNICAEN, Normandie UniversitéCaen, France
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Visual verticality perception after stroke: A systematic review of methodological approaches and suggestions for standardization. Ann Phys Rehabil Med 2017; 60:208-216. [PMID: 27079584 DOI: 10.1016/j.rehab.2016.02.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 02/03/2016] [Accepted: 02/07/2016] [Indexed: 11/22/2022]
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Subjective visual vertical with the bucket method in Brazilian healthy individuals. Braz J Otorhinolaryngol 2016; 82:442-6. [PMID: 26895747 PMCID: PMC9449031 DOI: 10.1016/j.bjorl.2015.08.027] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2015] [Revised: 08/16/2015] [Accepted: 08/26/2015] [Indexed: 11/21/2022] Open
Abstract
Introduction Objective Methods Results Conclusion
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Bonan IV, Leman MC, Legargasson JF, Guichard JP, Yelnik AP. Evolution of Subjective Visual Vertical Perturbation After Stroke. Neurorehabil Neural Repair 2016; 20:484-91. [PMID: 17082504 DOI: 10.1177/1545968306289295] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Objective. The perception of visual verticality is often perturbed after stroke and might be an underlying component of imbalance. The aim of this study was to describe the evolution of visual vertical (VV) perturbation and to investigate the factors affecting it. Methods. Thirty patients with hemiplegia after a single hemispheric stroke (17 left lesioned [LL] and 13 right lesioned [RL]) were studied. Visual verticality was tested within 45 days of stroke, and then at 3 and 6 months. Subjects sat in a dark room and adjusted a luminous rod to the vertical position. The differences between patients’ adjustments and vertical were calculated. The effects on VV evolution of the side, size, type, and location of the lesion were tested. Results. Sixty percent of the recent stroke patients had an initial inaccurate perception of verticality, and 39% of these patients recovered during the 1st 3 months after stroke. The evolution of VV tilt depended on the side of the lesion ( P = 0.01), with better recovery in LL patients. None of the other factors studied affected VV normalization. Conclusions. The poorer recovery of vertical perception after right-side stroke might be due to the predominant role of the right hemisphere in spatial cognition, and might be involved in the poorer recovery of balance after stroke in RL patients.
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Affiliation(s)
- I V Bonan
- Department of Physical Medicine and Rehabilitation, Groupe Hospitalier Lariboisière-F. Widal, Paris, France.
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Pavan TZ, Funabashi M, Carneiro JAO, Pontelli TEGDS, Tedeschi W, Colafêmina JF, Carneiro AAO. Software for subjective visual vertical assessment: an observational cross-sectional study. Braz J Otorhinolaryngol 2013; 78:51-8. [PMID: 23108820 PMCID: PMC9450785 DOI: 10.5935/1808-8694.20120008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Accepted: 06/10/2012] [Indexed: 11/20/2022] Open
Abstract
Spatial orientation in relation to the gravitational axis is significantly important for the maintenance of the posture, gait and for most of the human's motor activities. The subjective visual vertical exam evaluates the individual's perception of vertical orientation. Objectives The aims of this study were (1) to develop a virtual system to evaluate the subjective visual vertical exam, (2) to provide a simple tool to clinical practice and (3) to assess the subjective visual vertical values of h ealthy subjects using the new software. Study Design: observational cross-sectional study. Methods Thirty healthy volunteers performed the subjective visual vertical exam in both static and dynamic conditions. The exam consisted in adjusting a virtual line in the vertical position using the computer mouse. For the static condition, the virtual line was projected in a white background. For the dynamic condition, black circles rotated in clockwise or counterclockwise directions. Six measurements were taken and the mean deviations in relation to the real vertical calculated. Results The mean values of subjective visual vertical measurements were: static −0.372°; ± 1.21; dynamic clockwise 1.53° ± 1.80 and dynamic counterclockwise −1.11° ± 2.46. Conclusion This software showed to be practical and accurate to be used in clinical routines.
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Affiliation(s)
- Theo Zeferino Pavan
- Department of Physics, School of Philosophy, Sciences, and Literature of Ribeirão Preto, University of São Paulo, Ribeirão Preto - SP, Brazil
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Abstract
This chapter addresses the important and undertreated problem of balance disorders. The chapter has a simplified summary of the physiology of balance problems in order to set the scene. The issue of assessment is next addressed with discussion of important tests including the Berg Balance Scale and the Get Up and Go Test, and others. Posturography is discussed as well as assessment of the gravitional vertical. The assessment of vestibular function is of key importance and discussed in some detail. The focus of the chapter is on balance rehabilitation. Re-training of postural alignment and of sensory strategies are key but adaptation of the environment and re-training of cognitive strategies are also helpful in individual cases. Vestibular exercises can also be used. The chapter then critically analyses the efficacy of these treatments in specific balance disorders such as in stroke, Parkinson disease, polyneuropathies, multiple sclerosis, and vestibular disorders. Overall, there is a growing body of evidence that balance rehabilitation improves symptoms, function, and quality of life for those troubled by these disabling problems.
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Funabashi M, Santos-Pontelli TEG, Colafêmina JF, Pavan TZ, Carneiro AAO, Takayanagui OM. A new method to analyze the subjective visual vertical in patients with bilateral vestibular dysfunction. Clinics (Sao Paulo) 2012; 67:1127-31. [PMID: 23070337 PMCID: PMC3460013 DOI: 10.6061/clinics/2012(10)02] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Accepted: 05/20/2012] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVE The aim of this study was to assess the subjective visual vertical in patients with bilateral vestibular dysfunction and to propose a new method to analyze subjective visual vertical data in these patients. METHODS Static subjective visual vertical tests were performed in 40 subjects split into two groups. Group A consisted of 20 healthy volunteers, and Group B consisted of 20 patients with bilateral vestibular dysfunction. Each patient performed six measurements of the subjective visual vertical test, and the mean values were calculated and analyzed. RESULTS Analyses of the numerical values of subjective visual vertical deviations (the conventional method of analysis) showed that the mean deviation was 0.326±1.13º in Group A and 0.301±1.87º in Group B. However, by analyzing the absolute values of the subjective visual vertical (the new method of analysis proposed), the mean deviation became 1.35±0.48º in Group A and 2.152±0.93º in Group B. The difference in subjective visual vertical deviations between groups was statistically significant (p<0.05) only when the absolute values and the range of deviations were considered. CONCLUSION An analysis of the absolute values of the subjective visual vertical more accurately reflected the visual vertical misperception in patients with bilateral vestibular dysfunction.
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Affiliation(s)
- Martha Funabashi
- Department of Neurosciences and Behavior, School of Medicine at Ribeirão Preto, University of São Paulo, Ribeirão Preto/SP, Brazil
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Barra J, Pérennou D, Thilo KV, Gresty MA, Bronstein AM. The awareness of body orientation modulates the perception of visual vertical. Neuropsychologia 2012; 50:2492-8. [DOI: 10.1016/j.neuropsychologia.2012.06.021] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Revised: 06/18/2012] [Accepted: 06/26/2012] [Indexed: 11/26/2022]
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Luyat M, Noël M, Thery V, Gentaz E. Gender and line size factors modulate the deviations of the subjective visual vertical induced by head tilt. BMC Neurosci 2012; 13:28. [PMID: 22420467 PMCID: PMC3329413 DOI: 10.1186/1471-2202-13-28] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Accepted: 03/15/2012] [Indexed: 11/16/2022] Open
Abstract
Background The subjective visual vertical (SVV, the visual estimation of gravitational direction) is commonly considered as an indicator of the sense of orientation. The present study examined the impact of two methodological factors (the angle size of the stimulus and the participant's gender) on deviations of the SVV caused by head tilt. Forty healthy participants (20 men and 20 women) were asked to make visual vertical adjustments of a light bar with their head held vertically or roll-tilted by 30° to the left or to the right. Line angle sizes of 0.95° and 18.92° were presented. Results The SVV tended to move in the direction of head tilt in women but away from the direction of head tilt in men. Moreover, the head-tilt effect was also modulated by the stimulus' angle size. The large angle size led to deviations in the direction of head-tilt, whereas the small angle size had the opposite effect. Conclusions Our results showed that gender and line angle size have an impact on the evaluation of the SVV. These findings must be taken into account in the growing body of research that uses the SVV paradigm in disease settings. Moreover, this methodological issue may explain (at least in part) the discrepancies found in the literature on the head-tilt effect.
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Affiliation(s)
- Marion Luyat
- Department of Psychology, University of Lille, Laboratory of Functional Neurosciences and Pathology EA4559, 4 rue du Barreau, Villeneuve d'Ascq, 59653, France.
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Funabashi M, Silva NN, Watanabe LM, Santos-Pontelli TE, Colafêmina JF, Carneiro AA, Takayanagui OM. The use of a neck brace does not influence visual vertical perception. ARQUIVOS DE NEURO-PSIQUIATRIA 2011; 69:509-12. [PMID: 21755131 DOI: 10.1590/s0004-282x2011000400019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2010] [Accepted: 02/09/2011] [Indexed: 11/22/2022]
Abstract
Subjective visual vertical (SVV) evaluates the individual's capacity to determine the vertical orientation. Using a neck brace (NB) allow volunteers' heads fixation to reduce cephalic tilt during the exam, preventing compensatory ocular torsion and erroneous influence on SVV result. OBJECTIVE: To analyze the influence of somatosensory inputs caused by a NB on the SVV. METHOD: Thirty healthy volunteers performed static and dynamic SVV: six measures with and six without the NB. RESULTS: The mean values for static SVV were -0.075º±1.15º without NB and -0.372º±1.21º with NB. For dynamic SVV in clockwise direction were 1.73º±2.31º without NB and 1.53º±1.80º with NB. For dynamic SVV in counterclockwise direction was -1.50º±2.44º without NB and -1.11º±2.46º with NB. Differences between measurements with and without the NB were not statistically significant. CONCLUSION: Although the neck has many sensory receptors, the use of a NB does not provide sufficient afferent input to change healthy subjects' perception of visual verticality.
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Differential integration of visual and kinaesthetic signals to upright stance. Exp Brain Res 2011; 212:33-46. [DOI: 10.1007/s00221-011-2693-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2010] [Accepted: 04/08/2011] [Indexed: 10/18/2022]
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Barra J, Marquer A, Joassin R, Reymond C, Metge L, Chauvineau V, Pérennou D. Humans use internal models to construct and update a sense of verticality. Brain 2010; 133:3552-63. [PMID: 21097492 DOI: 10.1093/brain/awq311] [Citation(s) in RCA: 195] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Julien Barra
- Laboratoire de Psychologie et Neuropsychologie Cognitive, Université Paris Descartes, FRE 3292, France
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Joassin R, Bonniaud V, Barra J, Marquer A, Pérennou D. Somaesthetic perception of the vertical in spinal cord injured patients: A clinical study. Ann Phys Rehabil Med 2010; 53:568-74. [DOI: 10.1016/j.rehab.2010.07.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2010] [Accepted: 07/18/2010] [Indexed: 10/19/2022]
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Holly JE, Wood SJ, McCollum G. Phase-linking and the perceived motion during off-vertical axis rotation. BIOLOGICAL CYBERNETICS 2010; 102:9-29. [PMID: 19937069 PMCID: PMC2905236 DOI: 10.1007/s00422-009-0347-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2008] [Accepted: 11/02/2009] [Indexed: 05/28/2023]
Abstract
Human off-vertical axis rotation (OVAR) in the dark typically produces perceived motion about a cone, the amplitude of which changes as a function of frequency. This perception is commonly attributed to the fact that both the OVAR and the conical motion have a gravity vector that rotates about the subject. Little-known, however, is that this rotating-gravity explanation for perceived conical motion is inconsistent with basic observations about self-motion perception: (a) that the perceived vertical moves toward alignment with the gravito-inertial acceleration (GIA) and (b) that perceived translation arises from perceived linear acceleration, as derived from the portion of the GIA not associated with gravity. Mathematically proved in this article is the fact that during OVAR these properties imply mismatched phase of perceived tilt and translation, in contrast to the common perception of matched phases which correspond to conical motion with pivot at the bottom. This result demonstrates that an additional perceptual rule is required to explain perception in OVAR. This study investigates, both analytically and computationally, the phase relationship between tilt and translation at different stimulus rates-slow (45 degrees /s) and fast (180 degrees /s), and the three-dimensional shape of predicted perceived motion, under different sets of hypotheses about self-motion perception. We propose that for human motion perception, there is a phase-linking of tilt and translation movements to construct a perception of one's overall motion path. Alternative hypotheses to achieve the phase match were tested with three-dimensional computational models, comparing the output with published experimental reports. The best fit with experimental data was the hypothesis that the phase of perceived translation was linked to perceived tilt, while the perceived tilt was determined by the GIA. This hypothesis successfully predicted the bottom-pivot cone commonly reported and a reduced sense of tilt during fast OVAR. Similar considerations apply to the hilltop illusion often reported during horizontal linear oscillation. Known response properties of central neurons are consistent with this ability to phase-link translation with tilt. In addition, the competing "standard" model was mathematically proved to be unable to predict the bottom-pivot cone regardless of the values used for parameters in the model.
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Affiliation(s)
- Jan E Holly
- Department of Mathematics, Colby College, 5845 Mayflower Hill, Waterville, ME, 04901, USA.
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Pérennou DA, Mazibrada G, Chauvineau V, Greenwood R, Rothwell J, Gresty MA, Bronstein AM. Lateropulsion, pushing and verticality perception in hemisphere stroke: a causal relationship? Brain 2008; 131:2401-13. [PMID: 18678565 DOI: 10.1093/brain/awn170] [Citation(s) in RCA: 235] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- D A Pérennou
- Clinique de Médecine Physique et Réadaptation, Hôpital Nord-CHU Grenoble, Université Grenoble 1 degrees, Unité de Rééducation Neurologique du Grau du Roi, CHU Nîmes, France.
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Mazibrada G, Tariq S, Pérennou D, Gresty M, Greenwood R, Bronstein AM. The peripheral nervous system and the perception of verticality. Gait Posture 2008; 27:202-8. [PMID: 17498956 DOI: 10.1016/j.gaitpost.2007.03.006] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2005] [Revised: 03/14/2007] [Accepted: 03/19/2007] [Indexed: 02/02/2023]
Abstract
Orientation of the body with respect to gravity is based on integration of visual, vestibular and somatosensory signals. Here, we investigated the subjective postural vertical (SPV) and visual vertical (SVV) in three patients with bilateral somatosensory deafferentation and a group of age-matched normal subjects. Our hypothesis was that the patients with bilateral somatosensory deafferentation may show tilt induced bias in the construction of their SPV, with a normal SVV. Patient 1 had a severe Guillain Barré syndrome and almost complete absence of peripheral sensation, the two other patients had a thoracic spinal injury with a sensory loss from T6-7 down. On initial testing, compared with normal subjects and the patients with spinal injury, Patient 1 had a significant bias in SPV towards the side of a preceding tilt in both directions. Several months later, after significant improvement of sensation, this tilt-induced bias in SPV had resolved completely. In addition, Patient 1 had a significantly enlarged "cone of verticality", which did not change following improvement in peripheral sensation, reflecting persisting disturbance in the perception of body verticality. In the two patients with spinal injury, bias towards the side of a preceding tilt was not significant. These findings confirm the importance of somatosensory input from the trunk to the perception of SPV in the seated position.
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Affiliation(s)
- G Mazibrada
- Sobell Department of Neurophysiology, Institute of Neurology, Queen Square, London, UK.
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Bonan IV, Guettard E, Leman MC, Colle FM, Yelnik AP. Subjective Visual Vertical Perception Relates to Balance in Acute Stroke. Arch Phys Med Rehabil 2006; 87:642-6. [PMID: 16635626 DOI: 10.1016/j.apmr.2006.01.019] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2005] [Revised: 01/16/2006] [Accepted: 01/18/2006] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To determine whether misperception of the subjective visual vertical (SVV) underlies balance difficulties in hemiplegic patients. DESIGN Descriptive study, using a convenience sample. SETTING Department of physical medicine of a university hospital. PARTICIPANTS Thirty inpatients with hemiplegia after a hemispheric stroke during the 3 previous months. INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES The SVV was tested while subjects sat in a dark room and were asked to adjust a luminous line to the vertical position. Mean SVV deviation and uncertainty, defined as the standard deviation, were calculated for 8 trials. Balance was assessed by the Postural Assessment Scale for Stroke (PASS) and while patients sat on a laterally rocking platform placed on a Satel force platform. The mean body position and the instability score (Lx), calculated as the length of the course of the center of pressure, were recorded. Functional outcome was also evaluated by the FIM instrument. RESULTS An abnormal SVV was recorded for 20 of 30 patients. Balance (ie, PASS, Lx) and FIM correlated significantly with SVV tilt (P<.001, P=.01, and P<.001, respectively) and with uncertainty (PASS, P=.006; FIM, P=.003). CONCLUSIONS Verticality misperception was related to poor balance and might be an important element in the assessment of contributing factors to balance disorders after stroke. It should probably be taken into account when establishing balance rehabilitation programs for patients with hemiplegia.
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Affiliation(s)
- Isabelle V Bonan
- Department of Physical Medicine and Rehabilitation, Groupe Hospitalier Lariboisiere-F. Widal, Paris, France.
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Kaptein RG, Van Gisbergen JAM. Canal and Otolith Contributions to Visual Orientation Constancy During Sinusoidal Roll Rotation. J Neurophysiol 2006; 95:1936-48. [PMID: 16319209 DOI: 10.1152/jn.00856.2005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Using vestibular sensors to maintain visual stability during changes in head tilt, crucial when panoramic cues are not available, presents a computational challenge. Reliance on the otoliths requires a neural strategy for resolving their tilt/translation ambiguity, such as canal–otolith interaction or frequency segregation. The canal signal is subject to bandwidth limitations. In this study, we assessed the relative contribution of canal and otolith signals and investigated how they might be processed and combined. The experimental approach was to explore conditions with and without otolith contributions in a frequency range with various degrees of canal activation. We tested the perceptual stability of visual line orientation in six human subjects during passive sinusoidal roll tilt in the dark at frequencies from 0.05 to 0.4 Hz (30° peak to peak). Because subjects were constantly monitoring spatial motion of a visual line in the frontal plane, the paradigm required moment-to-moment updating for ongoing ego motion. Their task was to judge the total spatial sway of the line when it rotated sinusoidally at various amplitudes. From the responses we determined how the line had to be rotated to be perceived as stable in space. Tests were taken both with (subject upright) and without (subject supine) gravity cues. Analysis of these data showed that the compensation for body rotation in the computation of line orientation in space, although always incomplete, depended on vestibular rotation frequency and on the availability of gravity cues. In the supine condition, the compensation for ego motion showed a steep increase with frequency, compatible with an integrated canal signal. The improvement of performance in the upright condition, afforded by graviceptive cues from the otoliths, showed low-pass characteristics. Simulations showed that a linear combination of an integrated canal signal and a gravity-based signal can account for these results.
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Affiliation(s)
- Ronald G Kaptein
- Department of Biophysics, Radboud University Nijmegen, Geert Grooteplein 21, 6525 EZ Nijmegen, The Netherlands
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Saj A, Honoré J, Davroux J, Coello Y, Rousseaux M. Effect of Posture on the Perception of Verticality in Neglect Patients. Stroke 2005; 36:2203-5. [PMID: 16166576 DOI: 10.1161/01.str.0000182236.73502.19] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE The anticlockwise (ACW) deviation of the visual and visuohaptic subjective verticals (SVs), known to occur in patients with right hemisphere lesion, is amplified by spatial neglect (N). These patients have only been assessed when sitting. We investigated the hypothesis that postural changes modulate visuohaptic SV deviation. METHODS Eight patients presenting with a right hemisphere lesion and spatial N were compared with 6 matched control subjects (C). In the dark, they had to rotate a luminous rod to put it at the vertical in 4 conditions: (1) sitting with plantar sole support; (2) sitting without plantar sole support; (3) sitting with legs extended on a support; and (4) supine position. RESULTS N patients showed a significant ACW deviation (-4.5 degrees) of the SV compared with C subjects (+0.01 degrees). The effect of body position depended on the group (P=0.022) because changes had definite effects in the N but not in the C group. In fact, the former showed a reduction of the ACW deviation, from the first to the fourth condition. CONCLUSIONS Although the possible role of plantar and leg somaesthetic inputs remains to be thoroughly investigated, the modulation of gravitational inputs at trunk or vestibular level influences the SV deviation in N patients. This has to be put in relation with the modulation of N signs reported by other authors when passing from the sitting to the supine position.
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Affiliation(s)
- Arnaud Saj
- Service de Rééducation Neurologique and EA 2691, Hôpital Swynghedauw, CHRU de Lille, France.
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Kaptein RG, Van Gisbergen JAM. Nature of the Transition Between Two Modes of External Space Perception in Tilted Subjects. J Neurophysiol 2005; 93:3356-69. [PMID: 15673551 DOI: 10.1152/jn.01137.2004] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
A striking feature of visual verticality estimates in the dark is undercompensation for lateral body tilt. Earlier studies and models suggest that this so-called Aubert (A) effect increases gradually to around 130° tilt and then decays smoothly on approaching the inverted position. By contrast, we recently found an abrupt transition toward errors of opposite sign (E effect) when body tilt exceeded 135°. The present study was undertaken to clarify the nature of this transition. We tested the subjective visual vertical in stationary roll-tilted human subjects using various rotation paradigms and testing methods. Cluster analysis identified two clearly separate response modes (A or E effect), present in all conditions, which dominated in different but overlapping tilt ranges. Within the overlap zone, the subjective vertical appeared bistable on repeated testing with responses in both categories. The tilt range where bistability occurred depended on the direction of the preceding rotation (hysteresis). The overlap zone shifted to a smaller tilt angle when testing was preceded by a rotation through the inverted position, compared with short opposite rotations from upright. We discuss the possibility that the A-E transition reflects a reference shift from compensating line settings for the head deviation from upright to basing them on the tilt deviation of the feet from upright. In this scenario, both the A and the E effect reflect tilt undercompensation. To explain the hysteresis and the bistability, we propose that the transition is triggered when perceived body tilt, a signal with known noise and hysteresis properties, crosses a fixed threshold.
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Affiliation(s)
- Ronald G Kaptein
- Dept. of Biophysics, Radboud University Nijmegen, Geert Grooteplein 21, 6525 EZ Nijmegen, The Netherlands.
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Pérennou D. Vers une meilleure compréhension et une évaluation quantifiée du « pushing », un comportement postural dû à certains AVC. ACTA ACUST UNITED AC 2005; 48:198-206. [PMID: 15848263 DOI: 10.1016/j.annrmp.2004.10.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2004] [Accepted: 10/26/2004] [Indexed: 11/24/2022]
Abstract
INTRODUCTION Postural control aims to build up and align the body orientation (posture) and stabilize body segments. The existence of two separate mechanisms, one for the control of body orientation with respect to gravity and one for its stabilisation, is an emerging concept that allows a better understanding of postural disorders, including pushing, after stroke. Objectives. - Literature review concerning pushing, one of the most puzzling postural behaviours after stroke. METHODS Critical review of papers indexed in Medline and book chapters dealing with pushing. RESULTS There is no agreement about the definition of pushing: some authors consider that pushers push himself toward the paretic side using the healthy arm or leg; others consider that pushers lean (list) toward the side opposite the lesion and resist any attempt to become more upright. Surprisingly, the push itself has never been measured. Some ordinal scales have been recently proposed, but their psychometric properties have not been analysed. These methodological insufficiencies explain in part the disagreements about frequency (from 5% to 50% of patients with stroke) and cause(s) of pushing. CONCLUSION Pushing may be the most dramatic clinical manifestations of an extreme bias in the construction of the biological vertical. We argue for a better assessment of vertical perception/representation after stroke involving the three modalities of the biological (subjective) vertical: the visual vertical, the haptic or tactile vertical, and especially the postural vertical.
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Affiliation(s)
- D Pérennou
- Service de rééducation neurologique et Inserm ERM 207, centre de médecine physique et réadaptation, CHU de Dijon, France.
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Jarchow T, Wirz M, Haslwanter T, Dietz V, Straumann D. Perceived horizontal body position in healthy and paraplegic subjects: effect of centrifugation. J Neurophysiol 2003; 90:2973-7. [PMID: 12878718 DOI: 10.1152/jn.01129.2002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The perception of body position is mainly mediated by otolith information and visual cues. It has been shown, however, that proprioceptive sources are also involved. To distinguish between the contributions of the vestibular and nonvisual extra-vestibular information to graviception, we tested the effects of a stimulus that leaves the vestibular input unchanged but modifies the information from sense organs located more caudal along the trunk. This was achieved by bringing subjects into a horizontal ear-down position and rotating them around an earth-vertical axis that coincided with the interaural axis. In this paradigm, through centrifugal force, the stimulation of the vestibular and the putative extravestibular graviceptive organs in the body becomes dissociated. Healthy subjects (n = 14) and paraplegic patients with lesions between T4 and T8 (n = 7) adjusted themselves to the perceived horizontal right-ear down body position under two conditions: one with constant velocity rotation (ROT, velocity =120 degrees /s) around the earth-vertical axis of the turntable, and one without rotation (BASE). Among healthy subjects, the individual differences between BASE and ROT varied widely in both the feet-up or feet-down direction. In contrast, adjustments in paraplegic patients during ROT were always in the feet-down direction compared with BASE. A model with two extravestibular graviceptive sensors could explain our results: one sensor is located rostral to T4, and the other is caudal to T8. A load on the rostral graviceptor is interpreted as a tilt of the body in the feet-up direction and shifts the adjustments of perceived body position feet-down; a load on the caudal receptor is interpreted as a tilt in the feet-down direction and shifts the perceived body position feet-up. During ROT, healthy subjects solve the discrepant inputs of both extravestibular graviceptors in a highly variable manner, while paraplegic subjects show less variability because they are restricted to only the rostral graviceptor.
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Affiliation(s)
- T Jarchow
- Department of Psychology University of Zürich, CH-PO32 Zürich, Switzerland.
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Pavlou M, Wijnberg N, Faldon ME, Bronstein AM. Effect of semicircular canal stimulation on the perception of the visual vertical. J Neurophysiol 2003; 90:622-30. [PMID: 12649316 DOI: 10.1152/jn.00960.2002] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
UNLABELLED The subjective visual vertical (SVV) is usually considered a measure of otolith function. Herewith we investigate the influence of semicircular canal (SCC) stimulation on the SVV by rotating normal subjects in yaw about an earth-vertical axis, with velocity steps of +/- 90 degrees /s, for 60 s. SVV was assessed by setting an illuminated line to perceived earth vertical in darkness, during a per- and postrotary period. Four head positions were tested: upright, 30 degrees backward (chin up) or forward, and approximately 40 degrees forward from upright. During head upright/backward conditions, a significant SVV tilt (P < 0.01) in the direction opposite to rotation was found that reversed during postrotary responses. The rotationally induced SVV tilt had a time constant of decay of approximately 30 s. Rotation with the head 30 degrees forward did not affect SVV, whereas the 40 degrees forward tilt caused a direction reversal of SVV responses compared with head upright/backward. Spearman correlation values (Rho) between individual SCC efficiencies in different head positions and mean SVV tilts were 0.79 for posterior, 0.34 for anterior, and - 0.80 for horizontal SCCs. Three-dimensional video-oculography showed that SVV and torsional eye position measurements were highly correlated (0.83) and in the direction opposite to the slow phase torsional vestibuloocular reflex. IN CONCLUSION 1) during yaw axis rotation without reorientation of the head with respect to gravity, the SVV is influenced by SCC stimulation; 2) this effect is mediated by the vertical SCCs, particularly the posterior SCCs; 3) rotationally induced SVV changes are due to torsional ocular tilt; 4) SVV and ocular tilts occur in the "anticompensatory," fast phase direction of the torsional nystagmus; and 5) clinically, abnormal SVV tilts cannot be considered a specific indication of otolith system dysfunction.
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Affiliation(s)
- Marousa Pavlou
- Academic Department of Neuro-Otology, Division of Neuroscience and Psychological Medicine, Faculty of Medicine, Imperial College London, Charing Cross Hospital, London W6 8RF, United Kingdom
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Jaggi-Schwarz K, Hess BJM. Influence of dynamic tilts on the perception of earth-vertical. Exp Brain Res 2003; 149:340-50. [PMID: 12632236 DOI: 10.1007/s00221-002-1343-y] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2002] [Accepted: 11/06/2002] [Indexed: 11/28/2022]
Abstract
The aim of this study was to test the hypothesis that optimal activation of both the semicircular canals and the otoliths provides reliable vestibular cues about self-orientation in space. For this, we measured the ability of subjects to estimate the subjective vertical immediately, 20 s and 90 s after a rapid tilt (180 degrees /s(2)) from upright into different roll positions between 90 degrees left and right side down. Subjects had to estimate the earth-vertical and earth-horizontal direction in the dark by (a) setting a luminous line, (b) performing saccades, and (c) verbally declaring body position relative to gravity. The mean error curves from the three paradigms showed consistent E (Müller)- and A (Aubert)-effects, which did not significantly change over time. Horizontal and vertical saccade tasks exhibited different response characteristics, as previously reported by others, which likely reflect different computation mechanisms. The verbal estimation paradigm yielded complementary results to those of the luminous line paradigm and vertical saccade task. The E-effect of the luminous line and the vertical saccade paradigm might be explained by a bias towards earth-vertical due to interactions of vestibular and neck afferent signals. The invariably small A-effect of the luminous line and the vertical saccade paradigm probably reflects somatosensory signals that had relatively weak influence in our experiments. We conclude that phasic activation of the vestibular system reduces the influence of non-vestibular cues observed in low tilt velocity or static experiments. Although this activation generates an E-effect, the total error in the range of +/-90 degrees is reduced.
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Punt TD, Riddoch MJ. Towards a theoretical understanding of pushing behaviour in stroke patients. Neuropsychol Rehabil 2002. [DOI: 10.1080/09602010244000246] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Yelnik AP, Lebreton FO, Bonan IV, Colle FMC, Meurin FA, Guichard JP, Vicaut E. Perception of verticality after recent cerebral hemispheric stroke. Stroke 2002; 33:2247-53. [PMID: 12215595 DOI: 10.1161/01.str.0000027212.26686.48] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Perception of the subjective visual vertical (SVV) is affected by cerebral hemispheric lesions. Knowledge of this disturbance is of interest for the study of its possible relation to balance disturbances. There is still uncertainty about the possible effects of a visual field defect and of the side and site of the lesion. This study was conducted to assess SVV with the head upright or tilted and to explore its relation to a visual field defect, visuospatial neglect, and the site of lesion. METHODS Forty patients with hemiplegia after a recent hemispheric stroke (20 with left and 20 with right stroke) were studied. The site of the lesion was determined on CT scan, with special attention focused on the vestibular cortex. A neurological examination with determination of the visual field and visual neglect was conducted before SVV was tested. Subjects sat in a dark room and adjusted a luminous rod to the vertical position. Measures were repeated with binocular and monocular vision and with the head upright or tilted to the right or left. RESULTS SVV was abnormally deviated in 23 of 40 patients (57%). The deviation was significantly greater among patients with a right or left hemispheric lesion than among healthy controls (-2.2 degrees and 1.5 degrees versus 0.2 degrees ); the same applied to the range of uncertainty (7.6 degrees and 4.7 degrees versus 1.9 degrees ). SVV deviation was not significantly related to the location of the lesion but was closely related to visuospatial neglect. The "E" effect observed in controls with the head tilted, ie, an SVV shift in the direction opposite to the head tilt, was not observed in hemiplegic patients with the head tilted toward the nonparetic side. CONCLUSIONS Recent hemispheric stroke affects SVV perception, which is closely correlated to visuospatial neglect. It is suggested that the E effect might be mediated by the stretching of the somatosensory structure of the neck.
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Affiliation(s)
- Alain P Yelnik
- Physical Medicine and Rehabilitation Department, GH Lariboisiere-F. Widal, Paris, France.
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Van Beuzekom AD, Medendorp WP, Van Gisbergen JA. The subjective vertical and the sense of self orientation during active body tilt. Vision Res 2002; 41:3229-42. [PMID: 11718769 DOI: 10.1016/s0042-6989(01)00144-4] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Previous testing of the ability to set a luminous line to the direction of gravity in passively-tilted subjects, in darkness, has revealed a remarkable pattern of systematic errors at tilts beyond 60 degrees, as if body tilt is undercompensated or underestimated (Aubert or A-effect). We investigated whether these consistent deviations from orientation constancy can be avoided during active body tilt, where more potential cues about body tilt (e.g. proprioception and efference copy) are available. The effects of active body tilt on the subjective vertical and on the perception of self tilt were studied in six subjects. After adopting a laterally-tilted posture, while standing in a dark room, they indicated the subjective vertical by adjusting a visual line and gave their verbal estimate of head orientation, expressed on a clock scale. Head roll tilts covered the range from -150 degrees to +150 degrees. The subjective vertical results showed no sign of improvement. Actively-tilted subjects still exhibited the same pattern of systematic errors that characterised their performance during passive tilt. Random errors in this task showed a steep monotonic increase with tilt angle, as in earlier passive tilt experiments. By contrast, verbal head-tilt estimates in the active experiments showed a clear improvement and were now almost devoid of systematic errors, but the noise level remained high. Various models are discussed in an attempt to clarify how these task-related differences and the selective improvement of the self-tilt estimates in the active experiments may have come about.
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Affiliation(s)
- A D Van Beuzekom
- 231 Department of Medical Physics and Biophysics, University of Nijmegen, PO Box 9101, 6500 HB, Nijmegen, The Netherlands.
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Guerraz M, Luyat M, Poquin D, Ohlmann T. The role of neck afferents in subjective orientation in the visual and tactile sensory modalities. Acta Otolaryngol 2000; 120:735-8. [PMID: 11099150 DOI: 10.1080/000164800750000261] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
We studied the influence of neck afferents on the perception of orientation. In Experiment 1, we investigated the effect of head tilt on the subjective vertical in both the visual and tactile modalities. The results showed that head tilt triggers an Aubert effect in the visual modality and a Müller effect in the tactile modality. Significant positive correlations between the two adjustment modalities were restricted to head tilt to the left. In Experiment 2, we investigated the role of neck afferents on tactile orientation in seated and supine positions. The results showed that, in the supine position, the tactile E-effect was twice as large as in the seated position. These experiments confirm that tactile perception of orientation is affected by neck afferents, and show that the influence of neck afferents is limited by relevant gravitational cues.
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Affiliation(s)
- M Guerraz
- Laboratoire de Psychologie Expérimentale, UMR CNRS 5105, Grenoble.
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