Fig. 1.

Structure of the interleaved sequences in the within-sequence (top panel) and across-sequence (bottom panel) tasks. The syllables within a shaded region correspond to a repeated token. In half the presentations, the interleaved sequences consisted of only different stimuli (not shown) and in the other half, a repeat was introduced. In the within-sequence task, performance should improve when the sequences are heard as two separate streams, whereas in the across-sequence task, performance should improve when the interleaved sequences are heard as a single stream.