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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 3: Meanα of DFA on Day 0 (before the voyage began) for the three seasickness severity groups.The figure illustrates the statistically significant effect of seasickness severity groups. The error bars represent standard error of the mean.
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pone-0066949-g010: Experiment 3: Meanα of DFA on Day 0 (before the voyage began) for the three seasickness severity groups.The figure illustrates the statistically significant effect of seasickness severity groups. The error bars represent standard error of the mean.

Mentions: There were 33 participants. For positional variability of the COP, there were no significant effects. For the temporal dynamics of the COP, DFA revealed a significant main effect of seasickness severity groups, F(2,31)  = 6.98, p = .003, partial η2  = 0.317, which is illustrated in Figure 10. Post-hoc tests (multiple comparisons) revealed that the None group differed from the Mild group, p = .035, and from the Moderate/Severe group, p<.001. The Mild and Moderate/Severe groups did not differ from each other, p = .086. In addition, the Seasickness Group × Target Distance interaction was significant, F(2,31)  = 3.03, p = .045, partial η2  = 0.168 (Figure 11). Post-hoc tests revealed that α did not differ between the near target and horizon conditions for the None group or for the Mild group. For the Mod/Severe group, the mean difference was significant, p = 0.015; for this group, α was greater when looking at the horizon than when looking at the nearby target.


Getting Your Sea Legs.

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

Experiment 3: Meanα of DFA on Day 0 (before the voyage began) for the three seasickness severity groups.The figure illustrates the statistically significant effect of seasickness severity groups. The error bars represent standard error of the mean.
© Copyright Policy
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC3686767&req=5

pone-0066949-g010: Experiment 3: Meanα of DFA on Day 0 (before the voyage began) for the three seasickness severity groups.The figure illustrates the statistically significant effect of seasickness severity groups. The error bars represent standard error of the mean.
Mentions: There were 33 participants. For positional variability of the COP, there were no significant effects. For the temporal dynamics of the COP, DFA revealed a significant main effect of seasickness severity groups, F(2,31)  = 6.98, p = .003, partial η2  = 0.317, which is illustrated in Figure 10. Post-hoc tests (multiple comparisons) revealed that the None group differed from the Mild group, p = .035, and from the Moderate/Severe group, p<.001. The Mild and Moderate/Severe groups did not differ from each other, p = .086. In addition, the Seasickness Group × Target Distance interaction was significant, F(2,31)  = 3.03, p = .045, partial η2  = 0.168 (Figure 11). Post-hoc tests revealed that α did not differ between the near target and horizon conditions for the None group or for the Mild group. For the Mod/Severe group, the mean difference was significant, p = 0.015; for this group, α was greater when looking at the horizon than when looking at the nearby target.

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