Journal of Vestibular Research - Volume 29, issue 5

Authors: Massingale, Shelly | Alexander, Amy | Gerkin, Richard | Leddon, Charles | McQueary, Elizabeth | Allred, Richard Cameron | Pardini, Jamie E.

Article Type: Research Article

Abstract: BACKGROUND: The ability to clearly perceive an object while the head is in motion is important in athletics, as it relates to performance and potentially to injury prevention. Normative data for healthy adults on measures of gaze stability have been established. However, data for elite athletes is scarce. OBJECTIVE: To describe performance of elite athletes on computerized gaze stability testing and establish normative data for reference. METHODS: Data were acquired via retrospective chart review. 134 male professional baseball players completed computerized Visual Acuity, Visual Perception Time and Gaze Stability Tests as part of a multi-modal baseline …testing session. RESULTS: Performance of all athletes was superior to general population norms reported in the literature. There were no significant differences between the optimal and suboptimal consistency groups or between English-speaking and non- or limited-English speaking players. CONCLUSIONS: Similar to prior studies with smaller samples that have examined GST in athletes, we found high levels of GST performance in professional baseball players relative to normative data for the general population. Normative data for elite athletes was established using this healthy sample. This study underscores the importance of understanding the unique abilities of elite athletes when providing therapy after injury. Show more

Keywords: Gaze stability, elite athlete, sport

DOI: 10.3233/VES-190678

Citation: Journal of Vestibular Research, vol. 29, no. 5, pp. 221-228, 2019

Authors: Bretl, Kathrine N. | Sherman, Sage O. | Dixon, Jordan B. | Mitchell, Thomas R. | Clark, Torin K.

Article Type: Research Article

Abstract: BACKGROUND: Humans can adapt to the “Coriolis” cross-coupled illusion with repeated exposure, improving the tolerability of faster spin rates and enabling short-radius, intermittent centrifugation for artificial gravity implementation. OBJECTIVE: This investigation assesses the criticality of personalization in acclimation to the cross-coupled illusion. METHODS: We used the median stimulus sequence of our previous effective and tolerable personalized, threshold-based protocol to develop a standardized (non-personalized) approach. During each of 10, 25-minute sessions, the spin rate was incremented independent of whether each subject reported experiencing the cross-coupled illusion. RESULTS: In comparison to the previous personalized protocol, the …standardized protocol resulted in significantly reduced acclimation to the cross-coupled illusion (17.7 RPM threshold for the personalized protocol versus 11.8 RPM threshold for the standardized) and generally increased motion sickness reports (average reporting of 1.08/20 (personalized) versus 1.98/20 (standardized)), on average. However, the lack of individualization also leads to significantly less variance in subjects’ acclimation. CONCLUSIONS: These findings are critical for future missions that may require several astronauts to be acclimated concurrently, due to resource and time constraints. Assessing feasibility of fast spin rate, short-radius centrifugation is crucial for the future of artificial gravity implementation during spaceflight. Show more

Keywords: Artificial gravity, short-radius centrifuge, physiological countermeasure, standardized acclimation

DOI: 10.3233/VES-190673

Citation: Journal of Vestibular Research, vol. 29, no. 5, pp. 229-240, 2019

Authors: Clément, Gilles | Wood, Scott J. | Paloski, William H. | Reschke, Millard F.

Article Type: Research Article

Abstract: BACKGROUND: The vestibulo-ocular reflex (VOR) is a basic function of the vestibular system that stabilizes gaze during head movement. Investigations on how spaceflight affects VOR gain and phase are few, and the magnitude of observed changes varies considerably and depends on the protocols used. OBJECTIVE: We investigated whether the gain and phase of the VOR in darkness and the visually assisted VOR were affected during and after spaceflight. METHODS: We measured the VOR gain and phase of 4 astronauts during and after a Space Shuttle spaceflight while the subjects voluntary oscillated their head around the yaw …axis at 0.33 Hz or 1 Hz and fixed their gaze on a visual target (VVOR) or imagined this target when vision was occluded (DVOR). Eye position was recorded using electrooculography and angular velocity of the head was recorded with angular rate sensors. RESULTS: The VVOR gain at both oscillation frequencies remained near unity for all trials. DVOR gain was more variable inflight and postflight. Early inflight and immediately after the flight, DVOR gain was lower than before the flight. The phase between head and eye position was not altered by spaceflight. CONCLUSION: The decrease in DVOR gain early in the flight and after the flight reflects adaptive changes in central integration of vestibular and proprioceptive sensory inputs during active head movements. Show more

Keywords: Vestibular nystagmus, visual fixation, visual-vestibular interaction, microgravity, vestibulo-ocular reflex

DOI: 10.3233/VES-190670

Citation: Journal of Vestibular Research, vol. 29, no. 5, pp. 241-251, 2019

Authors: Lee, Geonho | Lee, Seul-Gi | Park, Hee-Sung | Kim, Bong Jik | Choi, Seong-Jun | Choi, Jin Woong

Article Type: Research Article

Abstract: BACKGROUND: Canal switch benign paroxysmal positional vertigo (CS-BPPV) is a transition of BPPV involving one canal to another canal during or after canalith repositioning procedures (CRP). OBJECTIVE: To investigate the clinical characteristics of CS-BPPV and its associated factors. METHODS: The data of 2,303 patients with BPPV involving the lateral canal (LC) or posterior canal (PC) were retrospectively analyzed. Demographics, etiologies, and various clinical parameters related to CRP were compared between patients with and without CS-BPPV. RESULTS: Sixty-eight (2.95%) patients exhibited CS-BPPV. For patients with CS-BPPV from the PC to the LC, as well as …those with CS-BPPV from the LC to the PC, the CRP number for the original canal in CS-BPPV was significantly greater than in non-CS-BPPV (P  = 0.002). More CRP cycles were required to treat CS-BPPV than non-CS-BPPV involving the same canal. Multivariate analysis showed that CS-BPPV from the LC to the PC was significantly associated with multiple CRP cycles and use of the Gufoni maneuver (P  = 0.038 and P  < 0.001, respectively). CONCLUSIONS: The use of multiple cycles of CRP and the Gufoni maneuver were significantly associated with the onset of CS-BPPV. Furthermore, more CRP cycles were needed for the treatment of CS-BPPV than for non-CS-BPPV involving the same canal. Show more

Keywords: Benign paroxysmal positional vertigo, canal conversion, canal switch, canalith repositioning procedures, Gufoni maneuver

DOI: 10.3233/VES-190667

Citation: Journal of Vestibular Research, vol. 29, no. 5, pp. 253-260, 2019

Authors: Micarelli, Alessandro | Viziano, Andrea | Lanzillotta, Alessia | Giorgino, Federica Maria | Pisano, Calogera | Ruvolo, Giovanni | Alessandrini, Marco

Article Type: Research Article

Abstract: BACKGROUND: Marfan syndrome (MFS) is a rare autosomal dominant connective tissue disorder affecting virtually every organ. Sleep disturbances, associated to high collapsibility in upper airways, are common in MFS; daytime sleepiness could lead to reduction in attention and motor coordination, with detrimental effects on balance. OBJECTIVE: To evaluate otoneurological function in MFS patients, compared to healthy subjects, and to investigate possible correlations with sleep deprivation extent. METHODS: Forty-one MFS patients underwent a thorough otoneurological examination, video Head Impulse Test (vHIT), and static posturography. Sleep parameters were recorded by home monitoring. Daytime sleepiness and dizziness-related handicap were …screened by means of Dizziness Handicap Inventory (DHI) and Epworth Sleepiness Scale (ESS). Results were compared with 49 healthy controls (HC). RESULTS: DHI and ESS scores were increased in MFS patients (p  < 0,01). vHIT scores showed no between-group effect. Classical (surface and length) and frequency-domain posturographic parameters were significantly increased in MFS with respect to HC (p  < 0,01). A positive correlation was found between ESS scores and posturographic parameters in MFS patients. CONCLUSIONS: An impaired postural control, related to the extent of sleep deprivation, was found in MFS patients. Such results could advocate for screening and treating sleep deprivation and balance dysfunctions in MFS patients. Show more

Keywords: Marfan syndrome, posturography, sleep apnea, sleep deprivation

DOI: 10.3233/VES-190684

Citation: Journal of Vestibular Research, vol. 29, no. 5, pp. 261-269, 2019

Authors: Holly, Jan E. | Cohen, Helen S. | Masood, M. Arjumand

Article Type: Research Article

Abstract: BACKGROUND: Perception of self-motion is difficult for patients to describe. In addition, the relationship between perceived rotation and eye movements is poorly understood, because most studies of patients have investigated only static orientation. OBJECTIVE: First, to determine whether patients with benign paroxysmal positional vertigo (BPPV) can use visual images to report perceived rotation elicited by the Dix-Hallpike maneuver. Second, to determine if the direction of patients’ perceptions align with data on classical nystagmus direction. METHODS: After the Dix-Hallpike maneuver, BPPV patients viewed images – sketches or video animations – representing possible perceived motions. They selected one …or more images representing perception. RESULTS: All subjects could select images. The directions of the videos were most often backward pitch and/ or ipsilateral roll and yaw relative to body orientation in the supine Dix-Hallpike position, generally consistent with the canal stimulus. Perceived direction of rotation was statistically significantly different from the direction of eye movements as published previously, suggesting a difference in mechanisms for perception and eye movements. CONCLUSION: Patients can easily learn to use a video language to describe their experiences. Perception is generally aligned with canal stimulus and nystagmus, but not exactly. Show more

Keywords: Spatial orientation, vertigo, nystagmus, self-motion perception

DOI: 10.3233/VES-190676

Citation: Journal of Vestibular Research, vol. 29, no. 5, pp. 271-279, 2019