Analysis of Heartbeat Tracking Tasks by Means of the Signal-Detection Theory

Heartbeat detection and tracking tasks are standard approaches for measuring comprehensive interoceptive abilities. Proper measures for the sensitivity of the conscious sensation of bodily signals, however, are rarely applied during analyses of such tasks. The present study aims to contribute significantly to this problem and, therefore, analyzes the data of a heartbeat-detection task (HBDT) by means of the signal-detection theory (SDT). The results (N = 44) showed that the sensitivity index (d') is significantly less dependent on the sheer number of putative detection reactions than traditional measures (accuracy scores) of interoceptive abilities. Hence, by using d', a prevalent criticized confounding can be resolved and thus the validity of the HBDT increases. In addition, evidence for the trainability of interoceptive awareness - as shown by past studies utilizing the traditional accuracy score - was also provided by use of the sensitivity index d'. A further novelty of this study is the application of duplex ultrasonography for the visualization of cardiac activity in a HBDT.