Real-time assessment of temperature sensitivity, pain processing, and pain behavior across the lifespan: Integrating stimulus data, contact force, and subjective ratings

Assessments of temperature sensitivity and pain processing play an important role in psychological and psychiatry research, including with adolescent participants and across the lifespan. To ensure the validity and comparability of findings, experimental settings must be well tolerated and easily manageable for participants of all age groups and reliably monitored by the experimenter. These settings should promote reproducible procedures and support computer-assisted data acquisition and analysis to enable robust, efficient scientific evaluation. We present CAREST (Controlling and Recording Experiments in Sensitivity to Temperature), a PsychoPy-based tool for real-time assessment of temperature sensitivity, pain sensation, and pain response behavior via thermal induction. CAREST controls and communicates with a cold/hot plate and provides a touchscreen slider to assess pain sensation on a visual analog scale (VAS). The plate is placed on a platform with load cells to measure hand-plate contact force, providing an objective assessment of thermal contact between hand and plate surface during the experiment and participants' approach versus avoidance tendencies in response to pain. CAREST continuously and synchronously records timestamped values of plate surface temperature, participants' VAS ratings, and hand-plate contact force, enabling computation of several established and novel measures of pain sensitivity and related behavioral factors within a single experimental setting. In a pilot study with 94 participants, we examined heat and cold pain thresholds, intensities, tolerances, and hand-plate contact forces. The results highlight substantial heterogeneity in pain response behavior, with one out of five participants differing markedly from the modest average tendency toward pain avoidance.