Experimental paradigm. (a) Subjects had to decide whether the fly occurred at a predefined position (0-back = low load) - one of the four corners of the screen - or whether the stimulus of the current trial occurred at the same position than the stimulus two trials before (2-back = high load). Before each visual stimulus a task irrelevant standard (88%) or a novel sound (12%) was presented. (b) In the displayed box the time line of one trial is shown.
Ruhnau et al. BMC Neuroscience 2010 11:126 doi:10.1186/1471-2202-11-126