Projects

Movement at sea


In 2009, APAL conducted the first experimental studies of the quantitative kinematics of human movement on ships at sea. At the invitation of the University-National Oceanographic Laboratory Systems (UNOLS) and the Semester at Sea program, we have conducted research on a several ships in nautical settings all over the world, calling in ports in Oceania, Hawaii, the Bahamas, Brazil, Chile, England, Russia, and Mexico, as well as Seattle, San Diego, and Duluth.

APAL research at sea addresses a wide variety of issues relating to the perception and control of the body, including suprapostural tasks, perceptual-motor learning, seasickness, mal de debarquement, and getting your sea legs. Working with Dr. Nick Stergiou at the University of Nebraska-Omaha, in April 2013 we conducted the first experimental studies of the quantitative kinematics of human gait at sea.

R/V Blue Heron

Operated by the University of Minnesota-Duluth Large Lakes Observatory

R/V Atlantis

Operated by the Woods Hole Oceanographic Institution

R/V Thomas G. Thompson

Operated by the University of Washington School of Oceanography

Publications

Stoffregen, T. A., Chen, F.-C., Varlet, M., Alcantara, C., & Bardy, B. G. (2013). Getting your sea legs. PLOS ONE, 8(6), e66949.

Chen, F.-C., & Stoffregen, T. A. (2012).  Specificity of postural sway to the demands of a precision task at sea.  Journal of Experimental Psychology: Applied, 18, 203-212.

Stoffregen, T. A., Villard, S., Chen, F.-C., & Yu, Y. (2011).  Standing body sway on land and at sea.  Ecological Psychology, 23, 19-36.

Mayo, A. M., Wade, M. G., & Stoffregen, T. A. (2011).  Postural effects of the horizon on land and at sea.  Psychological Science, 22, 118-124.

Yu, Y., Yank, J. R., Villard, S., & Stoffregen, T. A. (2010).  Postural activity and visual vigilance performance during rough seas. Aviation, Space, and Environmental Medicine, 81, 843-849.

Yu, Y., Yank, J. R., Katsumata, Y., Villard, S., Kennedy, R. S., & Stoffregen, T. A. (2010).  Visual vigilance performance and standing posture at sea.  Aviation, Space, and Environmental Medicine, 81, 375-382.

Stoffregen, T. A., Chen, F.-C., Yu, Y., & Villard, S. (2009). Stance width and angle at sea: Effects of sea state and body orientation.  Aviation, Space, and Environmental Medicine, 80, 845-849.

Stoffregen, T. A., Villard, S., & Yu, Y. (2009).  Body sway at sea for two visual tasks and three stance widths. Aviation, Space, and Environmental Medicine, 80, 1039-1043.


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Motion sickness


Motion sickness is an age-old problem, which has afflicted humanity for thousands of years. Historically, motion sickness has been associated with vehicles: Nausea derives from the Greek word for "ship".  In the past several decades, new motion sickness situations have emerged.  These include space flight (where motion sickness occurs during weightlessness), virtual environments, vehicle simulators, and video games. The cause of motion sickness remains controversial.

In APAL, we are studying motion sickness in three situations.

  1. In the moving room, our current research is focused on visually induced motion sickness as it relates to coordination of different body segments (torso and legs) and joints (hips and ankles) in the control of stance.
  2. In a separate series of studies, we are examining the nauseogenic properties of video games (XBox, Wii).  These studies are of direct relevance to the widespread (and increasing) incidence of motion sickness among people who play these game. 
  3. In addition, we exploit characteristics of video game technology to study general issues relating to the causes of motion sickness, including the role of active control vs. passive viewing.
  4. On ships at sea, we evaluate relations between movement data (posture and gait) and the occurrence of seasickness. 
  5. We study relations between body sway and subjective symptoms (e.g., nausea) that occur in situations not traditionally associated with motion sickness, such as morning sickness in pregnancy, and mild traumatic brain injury in boxers. 
Publications

Stoffregen, T. A., Chen, F.-C., Varlet, M., Alcantara, C., & Bardy, B. G. (2013). Getting your sea legs. PLOS ONE, 8(6), e66949. doi:10.1371/journal.pone.0066949

Chang, C.-H., Pan, W.-W., Chen, F.-C., & Stoffregen, T. A. (2013). Console video games, postural activity, and motion sickness during passive restraint. Experimental Brain Research, in press.

Chen, Y.-C., Tseng, T.-C., Hung, T.-H., Hsieh, C. C., Chen, F.-C., & Stoffregen, T. A. (2013). Cognitive and postural precursors of motion sickness in adolescent boxers. Gait & Posture, in press.

Yu, Y., Chung, H.-C., Hemingway, L., & Stoffregen, T. A. (2013). Standing body sway in women with and without morning sickness in pregnancy. Gait & Posture, 37, 103-107.

Chen, Y.-C., Hung, T.-H., Tseng, T.-C., Hsieh, C. C., Chen, F.-C., & Stoffregen, T. A. (2012). Pre-bout standing body sway differs between adult boxers who do and do not report post-bout motion sickness. PLOS ONE, 7(10): e46136. doi:10.1371/journal.pone.0046136.

Chen, Y.-C., Dong, X., Chen, F.-C., & Stoffregen, T. A. (2012). Control of a virtual avatar influences postural activity and motion sickness. Ecological Psychology, 24, 279-299.

Chang, C.-H., Pan, W.-W., Tseng, L.-Y., & Stoffregen, T. A. (2012). Postural activity and motion sickness during video game play in children and adults. Experimental Brain Research, 217, 299-309.

Dong, X., Yoshida, K., & Stoffregen, T. A. (2011). Control of a virtual vehicle influences postural activity and motion sickness. Journal of Experimental Psychology: Applied, 17, 128-138.

Stoffregen, T. A., Yoshida, K., Villard, S., Scibora, L., & Bardy, B. G. (2010). Stance width influences postural stability and motion sickness. Ecological Psychology, 22, 169-191.

Bonnet, C. T., Faugloire, E. M., Riley, M. A., Bardy, B. G., & Stoffregen, T. A. (2008). Self-induced motion sickness and body movement during passive restraint. Ecological Psychology.

Stoffregen, T. A., Faugloire, E., Yoshida, K, Flanagan, M., & Merhi, O. (2008). Motion sickness and postural sway in console video games. Human Factors, 50, 322-331.

Villard, S., Flanagan, M. B., Albanese, G., & Stoffregen, T. A. (2008). Postural instability and motion sickness in a virtual moving room. Human Factors, 50, 332-345.

Merhi, O., Faugloire, E., Flanagan, M., & Stoffregen, T. A. (2007). Motion sickness, console video games, and head mounted displays. Human Factors, 49, 920-934.

Faugloire, E., Bonnet, C. T., Riley, M. A., Bardy, B. G., & Stoffregen, T. A. (2007). Motion sickness, body movement, and claustrophobia during passive restraint. Experimental Brain Research, 177, 520-532.

Bonnet, C. T., Faugloire, E. M., Riley, M. A., Bardy, B. G., & Stoffregen, T. A. (2006). Motion sickness preceded by unstable displacements of the center of pressure. Human Movement Science, 25, 800-820.

Suprapostural tasks


Stoffregen, Smart, Bardy, & Pagulayan (1999) found that postural sway is often modulated so as to facilitate performance at the supra-postural task task of visual inspection (looking). This is in contrast to the more common assumption that visually-derived information is used primarily or exclusively to facilitate minimization of postural sway. Participants fixated targets at different distances. Earlier research has been interpreted as indicating that posture is controlled by optical flow from the nearest surface in the environment. We included a condition in which participants ignored a nearby surface and instead fixed a distance surface. In this condition, flow from nearby surface was available, but was irrelevant to the suprapostural looking task. As we had predicted, the amplitude of postural sway was related to the distance of fixation, and not to the distance of environmental surfaces, per se.

Stoffregen, Pagulayan, Bardy, & Hettinger (2000) extended the earlier findings to situations involving on-line changes in fixation distance. We also added a second, more constrained looking task. In addition to looking at simple graphical targets, in a second condition participants searched blocks of text for designated target letters. Results showed that the fixation distance effect can be observed across on-line changes in fixation distance. In addition, the distance effect was preserved during reading, and its magnitude is increased.


Affordance learning through body sway

Publications

Stoffregen, T. A., Yang, C.-M., Giveans, M. R., Flanagan, M., & Bardy, B. G. (2009). Movement in the perception of an affordance for wheelchair locomotion. Ecological Psychology, 21, 1-36.

Yu, Y., & Stoffregen, T. A. (2009, July). Locomotor and postural contributions to affordance perception. Talk presented at the 15th International Conference on Perception and Action, Minneapolis, MN.

Supported by a grant from the National Science Foundation.


Postural stabilization of visually-guided eye movements

In the study of Stoffregen, Pagulayan, Bardy, & Hettinger (2000) variation in supra-postural visual tasks involved changes in the difficulty of fixation (presumably, participants had to position their eyes more carefully in reading letters than in looking at a blank target), but also changes in the difficulty of eye movements (inspection tolerated by did not require eye movements, while the letter search task required the use of precisely guided eye movements). In a new study (currently under review), we examined relations between postural control and the execution of eye movements. Participants used eye movements to track very simple, side-to-side motion of targets on a computer monitor. Sway in this condition was compared with sway during fixation of a stationary target, and with sway when the eyes were closed and participants moved their eyes behind their lids. Sway was reduced during visually guided eye movements, relative to sway during stationary fixation, and relative to sway during eye movements with the eyes closed. We conclude that postural control can be used to facilitate the control of eye movements, but that this occurs only when eye movements are visually guided. When the eyes are closed, body sway has no effect on the accuracy of eye movements.

Publications

Stoffregen, T. A., Bardy, B. G., Bonnet, C. T., Hove, P., & Oullier, O. (2007). Postural sway and the frequency of horizontal eye movements. Motor Control, 11, 86-102.

Stoffregen, T. A., Bardy, B. G., Bonnet, C. T., & Pagulayan, R. J. (2006). Postural stabilization of visually guided eye movements. Ecological Psychology, 18, 191-222.

Carried out in collaboration with Dr. Benoît G. Bardy of the Universite' Montpellier-1. Supported by the National Science Foundation, the University of Montpellier-1, and the Institut Universitaire de France.


Task-specific postural responses to imposed optic flow

Publications

Stoffregen, T. A., Hove, P., Schmit, J., & Bardy, B. G. (2006). Voluntary and involuntary postural responses to imposed optic flow. Motor Control, 10, 24-33.

Carried out in collaboration with Dr. Benoît G. Bardy of the Universite' Montpellier-1. Our international collaboration was supported by grants from the National Science Foundation and the French Centre National de la Recherche Scientifique.


Postural stabilization of visual but not cognitive performance

In several studies, we have shown that the variability of postural movement is related to the level of demand of visual tasks that are performed while standing. Are such postural variations functional? One way to answer this question is to measure postural motion while participants perform different supra-postural tasks that are equated for "mental effort", but that differ in the level of visual demand. In our study, participants performed a visual signal detection task, or they performed mental arithmetic. Using a standard scale for mental workload, we showed that the subjective difficulty of the signal detection and mental arithmetic tasks did not differ. The signal detection task had a high level of visual demand, while the mental arithmetic task had none. The variability of postural motion was reduced during performance of the signal detection task, relative to sway during mental arithmetic. The results support our contention that task-specific changes in sway were functional. The results also suggest that theorists and experimenters may need to distinguish clearly between perceptual and non-perceptual supra-postural tasks in research relating postural to supra-postural activity (e.g., the dual task paradigm).

Publications

Stoffregen, T. A., Hove, P., Bardy, B. G., Riley, M. A., Bonnet, C. T. (2007). Postural stabilization of perceptual but not cognitive performance. Journal of Motor Behavior, 39, 126-138.

Lifespan issues

Among older adults, falling is the leading secondary cause of death. Falling is related to stability in control of the body. Research shows that older adults choose to avoid situations that challenge postural stability. Yet, at the same time, millions of older adults pay large sums of money to take vacation cruises, where they are subjected to ship motion 24/7, in 6 degrees of freedom and, often, on the order of meters. We have begun to investigate postural control and postural performance among older adults in both terrestrial and nautical settings.

Publications

Munafo, J., Wade, M. G., Stergiou, N., & Stoffregen, T. A. (2016). The rim and the ancient mariner: The nautical horizon affects postural sway in older adults. PLoS ONE, 11(12): e0166900. doi:10.1371/journal.pone.0166900.

Munafo, J., Curry, C., Wade, M. G., & Stoffregen, T. A. (2016). The distance of visual targets affects the spatial magnitude and multifractal scaling of standing body sway in younger and older adults. Experimental Brain Research, 234, 2721-2730.

Munafo, J., Wade, M. G., Stergiou, N., & Stoffregen, T. A. (2015). Subjective reports and postural performance among older adult passengers on a sea voyage. Ecological Psychology, 27, 127-143.

Prediction of athletic concussion


Motor control is affected by many clinical conditions, including traumatic brain injury. Several studies have shown that athletic concussion is followed by substantial changes in the control of standing body sway. Researchers have suggested that quantitative data on body sway can be used as an aid to diagnosis of athletic concussion, and for monitoring of recovery.

We have taken a qualitatively different approach to relations between body sway and traumatic brain injury. We measure standing body sway *before* athletes are exposed to situations that may result in concussive or sub-concussive brain injury. Our focus has been on competitive boxing. Before boxers enter the ring, we measure their standing body sway. After the completion of boxing matches we evaluate symptoms that are associated with concussive and sub-concussive brain injury. In several studies, we have found that body sway differs between boxers who later report symptoms and those who do not. Our research suggests that 1) there may be individual differences in susceptibility to traumatic brain injury, and 2) these individual differences may be reflected in characteristic patterns of body sway that can be measured (objectively, and non-invasively) before individuals are exposed to situations that may induce traumatic brain injury. If so, then it may be possible to use data on body sway to screen individuals for eligibility to participate in certain sports. >.

Publications

Chen, Y.-C., Tseng, T.-C., Hung, T.-H., & Stoffregen, T. A. (2014). Precursors of post-bout motion sickness in adolescent female boxers. Experimental Brain Research, DOI 10.1007/s00221-014-3910-4

Chen, Y.-C., Tseng, T.-C., Hung, T.-H., Hsieh, C. C., Chen, F.-C., & Stoffregen, T. A. (2013). Cognitive and postural precursors of motion sickness in adolescent boxers. Gait & Posture, 38, 795-799.

Chen, Y.-C., Hung, T.-H., Tseng, T.-C., Hsieh, C. C., Chen, F.-C., & Stoffregen, T. A. (2012). Pre-bout standing body sway differs between adult boxers who do and do not report post-bout motion sickness. PLOS ONE, 7(10): e46136. doi:10.1371/journal.pone.0046136.