A VERBAL DESCRIPTIONS OF THE SYSTEM
The following is the explanation provided to the participants in the negative verbal description
condition:

The first users of ADAPTIMINDTM reported that when using the system, it decreased
their task performance and increased stress making the task more difficult. As it is a
new and untried AI system, it is very unreliable and risky to implement in real-world
applications. In this study, we want to test these preliminary findings in a controlled
setting. We would like to evaluate your performance using AI and compare it to a

Preprint — do not distribute.

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The Placebo Effect Is Robust to Negative Descriptions of AI

condition where the AI is inactive (control condition). We will remind you in which of
the two conditions you are in before starting the tasks.

In the positive verbal description condition, only the system description was altered to reflect

the system positively:
AI enhance sour performance