Abstract
In this paper, we show that differences in reaction times (RT) to self-motion depend not only on the duration of the profile, but also on the actual time course of the acceleration. We previously proposed models that described direction discrimination thresholds for rotational and translational motions based on the dynamics of the vestibular sensory organs (otoliths and semi-circular canals). As these models have the potential to describe RT for different motion profiles (e.g., trapezoidal versus triangular acceleration profiles or varying profile durations), we validated these models by measuring RTs in human observers for a direction discrimination task using both translational and rotational motions varying in amplitude, duration and acceleration profile shape in a within-subjects design. In agreement with previous studies, amplitude and duration were found to affect RT, and importantly, we found an influence of the profile shape on RT. The models are able to fit the measured RTs with an accuracy of around 5 ms, and the best-fitting parameters are similar to those found from identifying the models based on threshold measurements. This confirms the validity of the modeling approach and links perceptual thresholds to RT. By establishing a link between vestibular thresholds for self-motion and RT, we show for the first time that RTs to purely inertial motion stimuli can be used as an alternative to threshold measurements for identifying self-motion perception models. This is advantageous, since RT tasks are less challenging for participants and make assessment of vestibular function less fatiguing. Further, our results provide strong evidence that the perceived timing of self-motion stimulation is largely influenced by the response dynamics of the vestibular sensory organs.
Highlights
The ability to model how and when we perceive selfmotion has several important implications
Since the perception of passive self-motion in the dark is mainly mediated by the vestibular system (Walsh 1961; Valko et al 2012), it provides a measure for vestibular function and has potential applications for diagnosing vestibular patients without the necessity to rely on oculomotor recordings (Merfeld et al 2010)
Since the mode is not obtained as part of the maximum likelihood fit there is no estimate of its standard deviation
Summary
The ability to model how and when we perceive selfmotion has several important implications. Exp Brain Res (2013) 228:51–62 as the vestibulo-ocular reflex (VOR). Both perception and action processes are determined by sensory signals from the vestibular system; differences in the response dynamics for perception and action have been reported and might reflect additional involvement of central processing (Merfeld et al 2004; Barnett-Cowan et al 2005; Merfeld et al 2005a, b; Bertolini et al 2011, 2012). Despite the importance of being able to model the perceived timing of self-motion, previous efforts have limited power as to date they have been restricted to exposing participants to sinusoidal acceleration profiles of different durations
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
