Figure 1.

Behavioral Results

(A) Adaptation paradigm. The perception of an ambiguous morphed image (A/B) was biased by the previous presentation of one of the pictures used to generate the morphing (picture A or picture B). The task of the subjects was to respond whether they recognized the ambiguous picture as A or B (here, presidents Bill Clinton and George Bush). (B) Mean percentage of trials in which subjects recognized the ambiguous image as B, when previously adapted to picture A (blue) or B (red). For comparison, the responses to the nonambiguous picture presentations (100% A and 100% B, likewise preceded by the adaptors) are also shown. (C) Same as (B) but separating between the 1–1.5 s and the 4 s presentation of the adaptors. The longer presentation of the adaptors led to a larger perceptual bias, namely the tendency to recognize the morphed picture as B when adapted to A (and vice versa). Error bars denote SEM.