The Threat of Scream paradigm: A tool for studying sustained physiological and subjective anxiety

Progress in understanding the emergence of pathological anxiety depends on the availability of paradigms effective in inducing anxiety in a simple, consistent and sustained way. Much progress has been made using the Threat-of-Shock paradigm (TOS), which generates anxiety through the delivery of unpredictable electric shocks to participants. However, TOS may be problematic when testing vulnerable populations. Moreover, it is not clear whether anxiety can be sustained throughout experiments of long duration. Here, we bring support for an alternative approach called the Threat-of-Scream paradigm (TOSc), in which the tactile delivery of shocks is replaced by the auditory delivery of distress screams. We report on an one-hour long study (plus its replication) in which participants were exposed to blocks before which they were told that they could hear aversive screams at any time (threat blocks), vs. blocks before which they were told that no scream will be heard (safe blocks). Both the experiment and its replication showed higher subjective reports of anxiety, higher skin conductance level, and positive correlation between the two measures, in threat compared to safe blocks. Anxiety measures were sustained throughout the experiments, suggesting little emotional and physiological habituation. Our results suggest that the delivery of low intensity distress screams can be an efficient, stable and cheap methodology to assess the impact of sustained anxiety on a diversity of cognitive functions and populations. We therefore believe the TOSc will become an essential part of the psychological toolkit, particularly so for researchers interested in the emergence of pathological anxiety.