Figure 3.
Event related potentials for midline electrodes (see Appendix for laterality effects) during the cue epoch confirm the effects described by the saliences in LV1 (Fig. 2). Black horizontal bars indicate onset and duration of cue (0 - 250 ms) and target (1000+ ms). Note that since ISI was variable (750 – 1000 ms) the waveform is contaminated by noise at time points greater than 1000 ms following cue onset. Shading indicates intervals showing reliable differences between saliences as assessed through bootstrap re-sampling and confirmed by univariate analyses. Three time windows show effects of context: frontal electrodes show this effect at a peak around 200 ms and again as a late slow negativity, posterior electrodes show the same effect midway through the interval, at P3b.