Tilman Stephani

ALT Figure 7A-C from the paper "Respiration, heartbeat, and conscious tactile perception" by Martin Grund and colleagues (2021, accepted for publication in the Journal of Neuroscience) shows that participants adapted their respiratory cycle to expected stimulus onsets to preferentially occur during late inspiration / early expiration. This closely matched heart rate variation (sinus arrhythmia) across the respiratory cycle such that most frequent stimulation onsets occurred during the period of highest heart rate probably indicating highest alertness and cortical excitability. Tactile detection rate was highest during the first quadrant after expiration onset. Inter-individually, stronger respiratory phase-locking to the task was associated with higher detection rates.

ALT Circular distribution of mean stimulus onsets relative to the respiratory cycle for (A) correct rejections (green), (B) misses (purple), and (C) hits (red). Zero degree indicates the inspiration onset. Each dot indicates a mean angle by one participant. The line around the inner circle shows the density distribution of these mean angles. The direction of the arrow in the center indicates the mean angle across the participants while the arrow length represents the mean resultant length R. The resulting p-value of the Rayleigh test of uniformity is noted below.