A PSYCHOPHYSICAL APPROACH TO MEASURE THE SENSE OF AGENCY
AbstractIncreasing a prosthesis user's sense of agency over their device may lead to improved patient outcomes. Measuring agency, however, can be difficult. Widely used questionnaires may be prone to cognitive biases and an established proxy for agency, the intentional binding paradigm, can be attentionally demanding. In this study, we present and test a novel psychophysical time discrimination task to detect the intentional binding effect, i.e. the perceived compression of the time interval between a controlled action and its effect. The task uses a two-alternative forced choice time comparison task to avoid the attentional demands associated with temporal estimation using an auxiliary clock display (such as a standard Libet clock protocol). We show that the psychophysics protocol can detect the intentional binding effect during voluntary movements in a small pilot study (n=4). Participants also completed a standard Libet clock protocol that showed inconsistent results. We conclude with a discussion of protocol improvements. The psychophysical time discrimination assessment shows promise for use as an objective sense of agency metric suitable for prosthesis users.
How to Cite
R. Steele, A. Shehata, J. Sensinger, J. Hebert, and D. Blustein, “A PSYCHOPHYSICAL APPROACH TO MEASURE THE SENSE OF AGENCY”, MEC Symposium, Aug. 2022.