Fig. 1

Experimental design. a Schematic illustration of the order in which subjects undertake memory tasks during the experiment. We apply the same smoothing procedure to this illustration and the data. (1) The initial order of tasks and fixation (405 ticks). (2) The fMRI method measures blood oxidation rather than the actual neural activity, which offsets the measurement. To offset the sequence by the same amount we convolve it with the hemodynamic response function (Glover 1999) (see (b)). (3) We apply a mean filter of width w=25 across the sequence. The final sequence is of length 381 ticks