Figure 8. Experiment 2: Intrasubject variability of the horizontal EOG: Mean and standard deviations of the EOG during the complete trial of every participant.
Top panels: attending the front speakers. Bottom panels: attending the back speakers. Left panels: younger adults. Right panels: older adults. Blue represents the EOG when attending the left, red when attending the right speaker. A positive EOG indicates that the gaze is directed toward the side of the attended speaker. Note that the deviation of the mean from is well within one standard deviation and therefore indicates that participants did not systematically divert their gaze to the attended speaker. The following figure supplements are available for Figure 8—figure supplement 1. Time-resolved EOG analysis in Experiment 2; Figure 8—figure supplement 2. Activity of the frontalis and zygomaticus muscle in Experiment 2.
Figure 8—figure supplement 1. Time-resolved activity (sampling points represent the energy within consecutive 10 s segments) after pooling the ipsi- and contralateral EOG signals for the front (left) and back speakers (right) in Experiment 2.
Figure 8—figure supplement 2. Grand average of the zygomaticus and frontalis muscle activity when stories were played from the front (top row) and back speakers (bottom row) in Experiment 2.
Shown is the normalized (total) energy of the left/right recording channels during attention to the left or right story (bars represent the standard error). There was no significant interaction of recording channel and attention direction [zygomaticus, frontalis: F(1, 19) = 0.13 and 3.44; 0.73 and 0.08; = 0.007 and 0.15].