Abstract
In 2021 a new measure for the assessment of cardiac interoceptive accuracy—
the Phase Adjustment Task (PAT)—was developed that overcomes several
limitations of existing methods and can be administered using a smartphone
application. In this report, we describe several refinements to the PAT.
These include: (1) triggering tones from the detection of the heartbeat
via the smartphone camera, rather than using an algorithm for predicting
the occurrence of the next heartbeat; (2) technical amendments to enable
implementation on iPhones with multiple cameras; (3) changes to instructions
and (4) changes to the collection of confidence ratings to improve participant
understanding and the utility of confidence ratings for interpretation of results;
(5) the introduction of new practice trials to improve clarity; (6) changes to
the analysis approach to identify cardiac phase-based heartbeat perceivers; (7)
a review of the use of continuous scores; (8) a reanalysis of data comparing
PAT performance in supervised laboratory settings and unsupervised remote
settings using the new analysis method, and (9) the implementation of
additional measures to discourage participants from checking their pulse. In
this paper we outline our justification for these changes and provide details
of where researchers can access the materials required for implementing
the PAT and analyzing data. Finally, we provide further recommendations
for implementation