Limits...
Getting Your Sea Legs.

Stoffregen TA, Chen FC, Varlet M, Alcantara C, Bardy BG - PLoS ONE (2013)

Bottom Line: We evaluated postural activity (stance width, stance angle, and the kinematics of body sway) before and during a sea voyage.Our results revealed rapid changes in postural activity among novices at sea.Body sway measured at sea differed among participants as a function of their (subsequent) experience of mal de debarquement.

View Article: PubMed Central - PubMed

Affiliation: Affordance Perception-Action Laboratory, University of Minnesota, Minneapolis, Minnesota, United States of America.

ABSTRACT
Sea travel mandates changes in the control of the body. The process by which we adapt bodily control to life at sea is known as getting one's sea legs. We conducted the first experimental study of bodily control as maritime novices adapted to motion of a ship at sea. We evaluated postural activity (stance width, stance angle, and the kinematics of body sway) before and during a sea voyage. In addition, we evaluated the role of the visible horizon in the control of body sway. Finally, we related data on postural activity to two subjective experiences that are associated with sea travel; seasickness, and mal de debarquement. Our results revealed rapid changes in postural activity among novices at sea. Before the beginning of the voyage, the temporal dynamics of body sway differed among participants as a function of their (subsequent) severity of seasickness. Body sway measured at sea differed among participants as a function of their (subsequent) experience of mal de debarquement. We discuss implications of these results for general theories of the perception and control of bodily orientation, for the etiology of motion sickness, and for general phenomena of perceptual-motor adaptation and learning.

No MeSH data available.


Related in: MedlinePlus

Experiment 2: Meanα of DFA as a function of days.The figure illustrates the statistically significant effect of days. The error bars represent standard error of the mean.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3686767&req=5

pone-0066949-g006: Experiment 2: Meanα of DFA as a function of days.The figure illustrates the statistically significant effect of days. The error bars represent standard error of the mean.

Mentions: For the temporal dynamics of sway, DFA revealed a significant main effect of days, F(2,56)  = 14.95, p<.001, partial η2  = 0.348. As shown in Figure 6, there was a reduction in self-similarity at sea, relative to values when the ship was at the dock. The main effect of axis was also significant, F(1,28)  = 11.15, p  = .002, partial η2  = 0.285, with mean α greater in ML (1.413) than in AP (1.372). Finally, the Days × Axis interaction was significant, F(2,56)  = 39.01, p<.001, partial η2  = 0.582. As can be seen in Figure 7, the relation between AP and ML that existed at the dock was reversed at sea. Post-hoc tests revealed that the transition from dock to sea had no effect on self-similarity in the ML axis. By contrast, in the AP axis, self-similarity at the dock (Day 0) was greater than on Day 1 or Day 2 (each p<.001), but self-similarity did not differ between the two days at sea (Day 1 vs. Day 2, p = .20).


Getting Your Sea Legs.

Stoffregen TA, Chen FC, Varlet M, Alcantara C, Bardy BG - PLoS ONE (2013)

Experiment 2: Meanα of DFA as a function of days.The figure illustrates the statistically significant effect of days. The error bars represent standard error of the mean.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3686767&req=5

pone-0066949-g006: Experiment 2: Meanα of DFA as a function of days.The figure illustrates the statistically significant effect of days. The error bars represent standard error of the mean.
Mentions: For the temporal dynamics of sway, DFA revealed a significant main effect of days, F(2,56)  = 14.95, p<.001, partial η2  = 0.348. As shown in Figure 6, there was a reduction in self-similarity at sea, relative to values when the ship was at the dock. The main effect of axis was also significant, F(1,28)  = 11.15, p  = .002, partial η2  = 0.285, with mean α greater in ML (1.413) than in AP (1.372). Finally, the Days × Axis interaction was significant, F(2,56)  = 39.01, p<.001, partial η2  = 0.582. As can be seen in Figure 7, the relation between AP and ML that existed at the dock was reversed at sea. Post-hoc tests revealed that the transition from dock to sea had no effect on self-similarity in the ML axis. By contrast, in the AP axis, self-similarity at the dock (Day 0) was greater than on Day 1 or Day 2 (each p<.001), but self-similarity did not differ between the two days at sea (Day 1 vs. Day 2, p = .20).

Bottom Line: We evaluated postural activity (stance width, stance angle, and the kinematics of body sway) before and during a sea voyage.Our results revealed rapid changes in postural activity among novices at sea.Body sway measured at sea differed among participants as a function of their (subsequent) experience of mal de debarquement.

View Article: PubMed Central - PubMed

Affiliation: Affordance Perception-Action Laboratory, University of Minnesota, Minneapolis, Minnesota, United States of America.

ABSTRACT
Sea travel mandates changes in the control of the body. The process by which we adapt bodily control to life at sea is known as getting one's sea legs. We conducted the first experimental study of bodily control as maritime novices adapted to motion of a ship at sea. We evaluated postural activity (stance width, stance angle, and the kinematics of body sway) before and during a sea voyage. In addition, we evaluated the role of the visible horizon in the control of body sway. Finally, we related data on postural activity to two subjective experiences that are associated with sea travel; seasickness, and mal de debarquement. Our results revealed rapid changes in postural activity among novices at sea. Before the beginning of the voyage, the temporal dynamics of body sway differed among participants as a function of their (subsequent) severity of seasickness. Body sway measured at sea differed among participants as a function of their (subsequent) experience of mal de debarquement. We discuss implications of these results for general theories of the perception and control of bodily orientation, for the etiology of motion sickness, and for general phenomena of perceptual-motor adaptation and learning.

No MeSH data available.


Related in: MedlinePlus