Figure 1

Perceptually bistable stimuli that repeat periodically. (A): The visual stimulus alternates between two frames f1 and f2 with a black square flipping between a position to the left (L) or right (R) of a fixed fixation point (+). (B): Schematic of repeating stimulus, illustrating that the black square alternates between the L (f1) and R (f2) locations over time. (C): Two perceptual interpretations are possible for the same repeating stimulus: (1) apparent motion where a single square appears to travel between the L and R locations, (2) blinking squares, where the squares appear to separately blink on and off at two distinct locations. (D): The auditory stimulus features alternating pure tones at frequencies A and B separated by a difference in frequency Δf. (E): Two perceptual interpretations are possible for the same repeating stimulus: (1) an integrated percept where both the A and B tone sequences are heard in a single alternating stream “ABABAB…”, (2) a segregated percept where the A tone sequence “A_A_A_…” is heard separately from the B tone sequence “_B_B_B…” (“_” is a silent gap)