Article Figures & Data
Figures
- Figure 1.
Interception responses as a function of the ball's acceleration, direction of movement, and the gravitational context. a, Average trigger time with respect to the arrival of the ball (mean ± SEM). b, Average within-subject difference in trigger time between above and below (mean ± SEM) for subjects that performed the experiment in both gravity conditions. c, Success rate.
- Figure 2.
Results of control tests. a, Effect of performing the experiment in normal gravity either on the ground or in level flight of the aircraft (n.s.). b, Effect of performing the experiment on the ground with or without the influence of anti-nausea medication (n.s.).
- Figure 3.
Idealized otolith characteristics based on known physiological properties. a, Gravity profile for a 20 s upside-down handstand in normal Earth gravity (blue) and for a single cycle in parabolic flight (red). b, Fictive cell discharge rates for hypothetical saccular cells that are preferentially sensitive to upward (Z+) or downward (Z−) acceleration. c, Net gravitational estimate based on a simple subtraction of Z+ and Z− activities. Green shading highlights when the change from hypergravity to 0g might generate a net, transient signal consistent with negative acceleration.
Tables
Effect Gravity as a group factor Gravity as a repeated measure F Significance F Significance Approach acceleration F(2,106) = 580.47 p < 0.001 F(2,34) = 333.78 p < 0.001 Approach duration F(2,106) = 26.47 p < 0.001 F(2,34) = 10.33 p < 0.001 Acceleration × duration F(4,212) = 33.45 p < 0.001 F(4,68) = 19.67 p < 0.001 Direction F(1,53) = 7.68 p < 0.01 F(1,17) = 2.47 n.s. Gravity F(1,53) = 0 n.s. F(1,17) = 0.84 n.s. Direction × gravity F(1,53) = 23.45 p < 0.001 F(1,17) = 14.87 p < 0.01
