Figure 1.
Effect of microgravity on VEP, ERSP and ITC recorded in occipital area (O2).
Grand average (n = 5) triggered (arrows and vertical dashed lines) by the checkerboard-reversal pattern (A–F) and by the 3D-tunnel-image (G–L) recorded on Earth before the flight (left) and in weightlessness. Statistical significance (Friedman ANOVA) p<0.05 is indicated by an asterisk.
Figure 2.
Effect of microgravity on VEP, ERSP and ITC recorded in frontal area (F8).
Same disposition as in Fig. 1. Statistical significance (Friedman ANOVA) p<0.05 is indicated by an asterisk.
Figure 3.
Effect of microgravity on the topographical representation of ITC and ERSP.
ITC are represented in the upper part (A–C) and the ERSP in lower part (D–F). Grand average (n = 5) triggered by the 3D-tunnel presentation on Earth before flight (A, D) in weightlessness (B, E) and on Earth after flight (C, F). Each map corresponds to a single recording channel (from F7–F8 to O1–O2) disposed on the scalp. Statistical significance (Friedman ANOVA) p<0.05 is indicated by an asterisk.
Figure 4.
Comparison between checkerboard and 3D tunnel stimuli given at 1 Hz in control participants on Earth.
From top to bottom, the ERS, ITC and ERP triggered by the checkerboard (A, C, E) and by the 3D-tunnel pattern (B, D, F). The triggers (vertical dashed lines) were given at time zero. The stars indicate stronger ERS in the upper alpha band (∼15 Hz) followed by a stronger ERD at about 200 ms in the upper alpha band (∼15 Hz) with respect to the checkerboard pattern.
Figure 5.
Effect of microgravity on the imaginary part of the coherency for the 3D-tunnel presentation.
Non-parametric Statistical t-test on imaginary part of the 10 Hz coherency (n = 5) at the P1 latency (∼100 ms) evoked by the 3D-tunnel-image, on Earth (A) and in weightlessness (B).
Figure 6.
Effect of microgravity on the imaginary part of the coherency for the checkerboard stimulation.
Non-parametric Statistical t-test on imaginary part of the 10 Hz coherency (n = 5) at the P1 latency (∼100 ms) evoked by the checkerboard stimulation, on Earth (A) and in weightlessness (B).
Figure 7.
Effect of microgravity on directionality.
Flow direction of information estimated by the phase-slope index on the imaginary part of the 10 Hz coherency for all pairs of channels averaged over all astronauts (n = 5) at the P1 latency (∼100 ms) evoked by the 3D-tunnel-image. The ith small circle is located at the ith electrode position and is a contour plot of the ith row of the matrix with elements ψ ij. On Earth (A), frontal areas are drivers and occipital areas are receivers. In weightlessness (B) flow is altered, splitting from the central area (drivers) into the frontal and occipital areas (receivers).