Visual Occlusion Decreases Motion Sickness in a Flight Simulator.

Sensory conflict theories of motion sickness (MS) assert that symptoms may result when incoming sensory inputs (e.g., visual and vestibular) contradict each other.

The Effects of Training on Anxiety and Task Performance in Simulated Suborbital Spaceflight.

Introduction: In commercial spaceflight, anxiety could become mission-impacting, causing negative experiences or endangering the flight itself. We studied layperson response to four varied-length training programs (ranging from 1 h-2 d of preparation) prior to centrifuge simulation of launch and re-entry acceleration profiles expected during suborbital spaceflight. We examined subject task execution, evaluating performance in high-stress conditions.

A Wearable Device Providing a Visual Fixation Point for the Alleviation of Motion Sickness Symptoms.

Objectives: Motion sickness (MS) can be problematic for many military operations. Some pharmaceutical countermeasures are effective but can lead to side effects. Non-pharmaceutical countermeasures vary in effectiveness and can require time to be beneficial (e.

Visual blur and motion sickness in an optokinetic drum.

Background: The most commonly cited hypotheses for motion sickness (MS) focus on inconsistent sensory inputs. Visual/vestibular conflicts may lead to MS, but visual input from retinal regions/neural pathways that are sensitive to motion might bear more weight in MS etiology. We hypothesized that inducing blurred vision in an optokinetic drum would attenuate the influence of foveal (parvocellular) input, but not peripheral (magnocellular) input that is sensitive to motion.

Space motion sickness and motion sickness: symptoms and etiology.

The adverse symptoms of space motion sickness (SMS) have remained problematic since the beginning of manned spaceflight. Despite over 50 yr of research SMS remains a problem that affects about half of all space travelers during the first 24-72 h of a spaceflight. SMS has been treated as another form of motion sickness (MS) despite distinct differences in symptomology.

Motion sickness adaptation to Coriolis-inducing head movements in a sustained G flight simulator.

Background: Technological advances have allowed centrifuges to become more than physiological testing and training devices; sustained G, fully interactive flight simulation is now possible. However, head movements under G can result in vestibular stimulation that can lead to motion sickness (MS) symptoms that are potentially distracting, nauseogenic, and unpleasant. In the current study an MS adaptation protocol was tested for head movements under +Gz.

Simulated angular head oscillation enhances vection in depth.

Research has shown that adding simulated linear head oscillation to radial optic flow displays enhances the illusion of self-motion in depth (ie linear vection). We examined whether this oscillation advantage for vection was due to either the added motion parallax or retinal slip generated by insufficient compensatory eye movement during display oscillation. We constructed radial flow displays which simulated 1 Hz horizontal linear head oscillation (generates motion parallax) or angular head oscillation in yaw (generates no motion parallax).

Simulated viewpoint jitter shakes sensory conflict accounts of vection.

Sensory conflict has been used to explain the way we perceive and control our self-motion, as well as the aetiology of motion sickness. However, recent research on simulated viewpoint jitter provides a strong challenge to one core prediction of these theories -- that increasing sensory conflict should always impair visually induced illusions of self-motion (known as vection). These studies show that jittering self-motion displays (thought to generate significant and sustained visual-vestibular conflict) actually induce superior vection to comparable non-jittering displays (thought to generate only minimal/transient sensory conflict).

The sickening rug: a repeating static pattern that leads to motion-sickness-like symptoms.

The nauseogenic properties of a patterned rug that reputedly caused motion-sickness-like symptoms in those who viewed it was the topic of this study. Naive observers viewed a 1:1 scale image of the black-and-white patterned rug and a homogeneous gray region of equivalent luminance in a counterbalanced within-subjects design. After 5 min of viewing, symptoms were assessed with the simulator sickness questionnaire (SSQ), yielding a total SSQ score and sub-scores for nausea, oculomotor symptoms, and disorientation.

Natural visual-field features enhance vection.

When a large optic-flow pattern is viewed, induced self-motion perception (vection) can result even for observers who are stationary relative to Earth. Vection is common in optokinetic drums, large-screen cinemas, vehicle simulators, and other virtual environments. However, not all optic-flow patterns are equally effective in producing vection.

Combined pitch and roll and cybersickness in a virtual environment.

Background: Stationary subjects who perceive visually induced illusions of self-motion, or vection, in virtual reality (VR) often experience cybersickness, the symptoms of which are similar to those experienced during motion sickness. An experiment was conducted to test the effects of single and dual-axis rotation of a virtual environment on cybersickness. It was predicted that VR displays which induced illusory dual-axis (as opposed to single-axis) self-rotations in stationary subjects would generate more sensory conflict and subsequently more cybersickness.

Expanding and contracting optic-flow patterns and vection.

When stationary observers view an optic-flow pattern, visually induced self-motion perception (vection) and a form of motion sickness known as simulator sickness (SS), can result. Previous results suggest that an expanding flow pattern leads to more SS than a contracting pattern. Sensory conflict, a possible cause of SS, may be more salient when an expanding optic-flow pattern is viewed.

Vertical display oscillation effects on forward vection and simulator sickness.

Background: The current study investigated the effects that vertical display oscillation had on the development of both vection and simulator sickness.

Methods: There were 16 subjects who were exposed to optic flow displays which simulated either: 1) constant velocity forward self-motion (pure radial flow); or 2) combined constant velocity forward and vertically oscillating self-motion (radial flow with vertical oscillation at one of three frequencies: 1.8, 3.

Expanding and contracting optical flow patterns and simulator sickness.

Background: Sensory conflict may be a factor in simulator sickness (SS) given that visual input is often inconsistent with other sensory inputs. It was predicted that an expanding optical flow pattern would lead to more sensory conflict, and subsequently more SS than a contracting pattern.

Methods: There were 16 individuals who participated in the experiment (6 men, 10 women, mean age = 24.