Article

Vestibular Labyrinth Contributions to Human Whole-Body Motion Discrimination

Departments of Otology and Laryngology and Neurology, Harvard Medical School, and Jenks Vestibular Physiology Laboratory, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts 02114.
The Journal of Neuroscience : The Official Journal of the Society for Neuroscience (Impact Factor: 6.34). 09/2012; 32(39):13537-42. DOI: 10.1523/JNEUROSCI.2157-12.2012
Source: PubMed

ABSTRACT

To assess the contributions of the vestibular system to whole-body motion discrimination in the dark, we measured direction recognition thresholds as a function of frequency for yaw rotation, superior-inferior translation ("z-translation"), interaural translation ("y-translation"), and roll tilt for 14 normal subjects and for 3 patients following total bilateral vestibular ablation. The patients had significantly higher average threshold measurements than normal (p < 0.01) for yaw rotation (depending upon frequency, 5.4× to 15.7× greater), z-translation (8.3× to 56.8× greater), y-translation (1.7× to 4.5× greater), and roll tilt (1.3× to 3.0× greater)-establishing the predominant contributions of the vestibular system for these motions in the dark.

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Available from: Adrian J Priesol, Dec 26, 2013
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    • "Given the dynamic ranges (i.e., 04 frequency ranges) investigated, these measured threshold variations as a function of frequency typically reflect 05 peripheral transduction processes and typically have not told us much about decision-making dynamics. With 06 the exception of some vestibular threshold studies (e.g., Benson et al. 1989; Benson et al. 1986; Grabherr et al. 07 2008; Haburcakova et al. 2012; Karmali et al. 2014; Lewis et al. 2011a; b; Lim and Merfeld 2012; Mardirossian 08 et al. 2014; Priesol et al. 2014; Soyka et al. 2012; Soyka et al. 2011; Valko et al. 2012), decision-making 09 studies using signal detection methods have rarely focused on dynamics (e.g., perceptual decisions as a 10 function of frequency , where the frequency is in a range relevant to decision -making as opposed to sensory 11 transduction ). As discussed later in this review , such vestibular threshold studies may help inform us about 12 decision - making dynamics because behaviorally relevant stimulus frequencies overlap with frequencies 13 influenced by decision - making dynamics . "
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    • "In addition to this, we measured thresholds at two different frequencies because vestibular thresholds depend on frequency (Grabherr et al. 2008; Valko et al. 2012). Importantly, Karmali et al. (2014), who directly compared visual and vestibular motion perception, found lower visual thresholds at frequencies between 0.1 and 1 Hz and observed the opposite pattern at frequencies higher than 2 Hz. "
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    • "The optokinetically induced effect is likely to be stronger in vestibular patients because they rely more on visual information than healthy controls (Huygen et al. 1989; Huygen and Verhagen 2011). Recently, Valko et al. (2012) tested dynamic tilt perception in patients with total vestibular loss, showing motion discrimination thresholds during roll rotation about twice as high as healthy controls. While this indicates an important role of vestibular cues in dynamic tilt perception, caution should be taken when extrapolating their results to static tilt perception, for which contribution of other extravestibular cues might be weighted more heavily. "
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