Figure 1. Observational slot machine task with hidden outcomes.

(A) Trial timeline. The first screen signals whether the agent or the participant has to make a choice. Subsequently two slot machines are presented, along with on agent trials a (pseudo) video feed of the agent making a selection, and the choice of the slot machine is revealed after a jittered interval. (B) The probabilistic food distribution behind the slot machines: each of the three slot machines is labeled by a unique fractal and yields the same three food items, but at differing stationary probabilities, as indicated in the table. (C) Agent and participant choice ratio. Choice ratio is defined as choice frequency of a slot machine given its total number of presentations. Agent performance (grey bars) are collapsed across conditions, and depicted in agent-referential space. Participant performance (cyan for similar, pink for dissimilar) is depicted in self-referential space. Regardless of whether they are observing a similar or dissimilar agent, participants are equally good at choosing their best slot machine, nearly matching the agent’s performance.

Figure 1—figure supplement 1. Additional task information.

(A) Pre-MRI phase and agent preferences construction: Participants first made pairwise food comparisons before entering the MRI sessions. From their actual food rating, we then constructed one similar and one dissimilar agent (B) Learning curve of agent (across both conditions, grey) and participant (separately for similar and dissimilar). Dotted line depicts plateau of agent behavior (C) Debrief: All participants classified agents correctly as similar, resp. dissimilar.