Deception in stress reactivity and recovery research.

OBJECTIVE Testing stress reactivity in the laboratory often requires deception or at least concealment of the hypothesis in order to mimic real-life provocations. Researchers routinely conduct a post-experimental validity check about the success of deception in order to rule out competing hypotheses. The research literature on the impact of failed deception offers contradictory results about the 'cost' of failed deception. To date, no evaluation of this threat to internal validity has used objective physiological indices to assess the extent of damage to the results when deception or concealment fails. In this study we evaluated whether or not post-experimental assessment of participants' ability to see through a protocol affected physiological and subjective responses to an anger-provoking laboratory task. METHOD One hundred and thirty-seven participants were subjected to an anger provocation task disguised as a 'cognitively challenging arithmetic task'. RESULTS Forty-six participants declared during debriefing that they had seen through or suspected that the underlying hypotheses were related to anger provocation but neither blood pressure, heart rate, or self-reported affect responses to the tasks differentiated the 'aware' from the 'unaware' group. DISCUSSION We posit that concealment of the hypothesis in anger provocation experiments is usually effective and may not be a threat to the study's internal validity.