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Fig. 3. Study Procedure: In this mixed-design study examining the induction of placebo and nocebo effects,
participants were divided into two groups (Description), with each group receiving altered system descriptions.
Participants in each group performed a letter discrimination task under two conditions (Status): in the sham-
AI condition, they were informed the task pace was adjusted by an AI system based on their measured stress
responses; in the No-AI condition, they were told adjustments in task pace were random. Before and after
interacting with the sham-AI system, expectations on performance with and without the sham-AI system set
as active were assessed. After the tasks and before debriefing, additional questionnaires assessing i.e., user
experience and AI literacy were implemented. Ultimately, we revealed the manipulation and assessed the
participants’ belief in the manipulation.
AI enhance sour performance