Assessment of Olfactory Perception in Individuals with Motion Sickness.

Background: Individuals who experience motion sickness (MS) frequently mention the presence of smells in the environment as a factor favoring the occurrence of MS symptoms. The aim of the present work was to compare olfactory function in MS sensitive (MS+) and insensitive (MS-) subjects.

Methods: Olfactory testing included determination of odor detection thresholds, subjective evaluation of the quality (intensity, hedonicity, and familiarity) of three different odorants (limonene, isovaleric acid, and petrol) as well as measures of skin conductance responses to these three odorants.

Prevalence, Predictors, and Prevention of Motion Sickness in Zero-G Parabolic Flights.

Introduction: Zero-G parabolic flight reproduces the weightlessness of space for short periods. However, motion sickness may affect some fliers. The aim was to assess the extent of this problem and to find possible predictors and modifying factors.

Oscillatory neural responses evoked by natural vestibular stimuli in humans.

While there have been numerous studies of the vestibular system in mammals, less is known about the brain mechanisms of vestibular processing in humans. In particular, of the studies that have been carried out in humans over the last 30 years, none has investigated how vestibular stimulation (VS) affects cortical oscillations. Here we recorded high-density electroencephalography (EEG) in healthy human subjects and a group of bilateral vestibular loss patients (BVPs) undergoing transient and constant-velocity passive whole body yaw rotations, focusing our analyses on the modulation of cortical oscillations in response to natural VS.

Visual inference of arm movement is constrained by motor representations.

Several studies support the idea that motion inference is strongly motor dependent. In the present study, we address the role of biomechanical constraints in motion prediction and how this implicit knowledge can interfere in a spatial prediction task. Right-handed (RHS) and left-handed subjects (LHS) had to estimate the final position of a horizontal arm movement in which the final part of the trajectory was hidden.

Visually induced motion sickness can be alleviated by pleasant odors.

Visually induced motion sickness (VIMS) is a common side effect in virtual environments and simulators. Several countermeasures against VIMS exist, but a reliable method to prevent or ease VIMS is unfortunately still missing. In the present study, we tested whether olfactory cues can alleviate VIMS.

Vestibular evoked potentials (VsEPs) of cortical origin produced by impulsive acceleration applied at the nasion.

We report the results of a study to record vestibular evoked potentials (VsEPs) of cortical origin produced by impulsive acceleration (IA). In a sample of 12 healthy participants, evoked potentials recorded by 70 channel electroencephalography were obtained by IA stimulation at the nasion and compared with evoked potentials from the same stimulus applied to the forefingers. The nasion stimulation gave rise to a series of positive and negative deflections in the latency range of 26-72 ms, which were dependent on the polarity of the applied IA.

Sensorial countermeasures for vestibular spatial disorientation.

Spatial disorientation is defined as an erroneous body orientation perceived by pilots during flights. Limits of the vestibular system provoke frequent spatial disorientation mishaps. Although vestibular spatial disorientation is experienced frequently in aviation, there is no intuitive countermeasure against spatial disorientation mishaps to date.

Vestibular receptors contribute to cortical auditory evoked potentials.

Acoustic sensitivity of the vestibular apparatus is well-established, but the contribution of vestibular receptors to the late auditory evoked potentials of cortical origin is unknown. Evoked potentials from 500 Hz tone pips were recorded using 70 channel EEG at several intensities below and above the vestibular acoustic threshold, as determined by vestibular evoked myogenic potentials (VEMPs). In healthy subjects both auditory mid- and long-latency auditory evoked potentials (AEPs), consisting of Na, Pa, N1 and P2 waves, were observed in the sub-threshold conditions.

Thresholds for vestibular-evoked myogenic potentials (VEMPs) produced by impulsive transmastoid acceleration.

Objective: To evaluate methods for estimating thresholds of vestibular evoked myogenic potentials (VEMPs) and ocular VEMPs (OVEMPs) produced by impulsive transmastoid acceleration (ITA).

Design: VEMPs and OVEMPs were obtained simultaneously from subjects in supine posture with both head and eyes elevated. Thresholds to ITA were measured using four different response identification methods.

Contributions of ocular vestibular evoked myogenic potentials and the electrooculogram to periocular potentials produced by whole-body vibration.

In this paper we report the results of an experiment to investigate the emergence of ocular vestibular evoked myogenic potentials (OVEMPs) during the linear vestibular ocular reflex (LVOR) evoked by whole-body vibration (WBV). OVEMP and electrooculogram (EOG) montages were employed to record periocular potentials (POPs) from six subjects during WBV in the nasooccipital (NO) axis over a range of frequencies from 0.5 to 64 Hz with approximately constant peak head acceleration of 1.

Variability of EEG synchronization prior to and during observation and execution of a sequential finger movement.

The aim of this study was to test the validity of mirror neuron activity in humans through analysis of electroencephalographic (EEG) functional connectivity during an action not directed towards an object. We investigated changes in EEG interchannel synchronization prior to and during action execution and also prior to and during observation of the same action. Twelve participants observed a simple finger movement sequence.