Figure 4.

MEG task

(A) The task consisted of an inference and probe phase. During inference, subjects were presented with a silhouette and had to infer its relational composition. During probe, subjects were presented with two building blocks and were asked to indicate the relation between these two building blocks in the previous silhouette, if any.

(B) Subjects’ performance on the task improved over time.

(C) The MEG experiment started with a functional localizer, where subjects observed individual building blocks with different textures (wood, concrete, steel, or bricks) on the screen. Intermittently, they received a probe question. The functional localizer was followed by a rest session, followed by three task sessions. The task was identical to training, except that we included an additional probe time window in which subjects were asked to infer the relation between two building blocks but could not yet indicate a response. The three task sessions were followed by another rest, followed by another three task sessions and a final rest session.

(D) Subjects’ performance again improved over time, such that the proportion of correct responses increased, and reaction times decreased, with ongoing task experience.

(E) In the MEG experiment, one building block was always present in every silhouette (stable, highlighted in red for an example stimulus set, see Figure S4 for all used stimuli), whereas two out of the remaining three had to be inferred (present) and one building block was absent.

Shaded colored areas reflect standard errors.