The temporal locations of heartbeat sensations.

This experiment examined individual differences in the temporal location of heartbeat sensations and the reliability of their detection. Following practice on a familiarization task in judging light-tone simultaneity, 50 subjects were studied for two sessions on a heartbeat detection task, which required judging the simultaneity of heartbeat sensations and tones presented at six intervals following the onset of ventricular contraction. Subjects inspected the heartbeat-tone intervals as frequently and for as long as desired before choosing the one in which heartbeat sensations and tones were most simultaneous. The temporal locations of heartbeat sensations in subjects classified as "good heartbeat perceivers" (n = 16) ranged from 131 and 363 ms following ventricular contraction (mean = 228 ms). Correlations between the familiarization and heartbeat detection tasks in the accuracy of simultaneity judgments and in the frequency and duration of interval inspections suggest that general perceptual abilities and strategies may underlie success in detecting heartbeat sensations.