Figure 1.
Experimental design. A, The screening session was based on a temporal order judgment task and comprised three conditions: no adaptation, audio-leading adaptation (A200V) and visual-leading adaptation (V200A). We assessed the individual bias in temporal order perception (PSSno), adapted PSSs (PSSA200V and PSSV200A), and JNDs. B, Schematics of a psychometric curve obtained after the screening session. The PSS was defined as the SOA for which a participant's performance was at chance level (50%). The JNDs were defined as the SOAs for which a participant's performance was at 30% (JND1) and 70% (JND2) of performance. If a participant has a negative PSS as shown here, i.e., the sound needs to be presented first so that s/he can perceive simultaneity, s/he has an increased tendency to reply Vfirst (matching-bias response) compared with Afirst (against-bias response). C, In the EEG session, the two JNDs derived per condition in the screening session were used as SOAs. D, The correctness and biasedness contrasts are fully orthogonal, and they comprise the same number of audio-leading and visual-leading pairs.