Fig. 5.

(Left) Physiological-noise magnitudes from the silent periods in the inattention (white bars), and dichotic-listening conditions (black bars), averaged across eight subjects. These data were collected from triplet 1. Error bars show one standard deviation. The physiological-noise magnitudes recorded in the ear canals of our subjects were lower in the dichotic-listening condition than in the inattention condition, and this was true for all eight subjects individually (see Table 2). The mean difference between conditions was statistically significant. (Right) Physical noise-floor magnitudes calculated across three repeated measures of each condition in a passive cavity (a syringe). Error bars show one standard deviation. In contrast with the human data, the physical noise-floor magnitudes recorded in the passive cavity did not differ across conditions.