Procedure

Twenty participants were randomly assigned in equal number to one of the two cue conditions. In the cued condition, a row of asterisks was presented on a screen 500 msec before the onset of break signal. This condition was compared with a no-cue condition, where no asterisks were presented. Location and duration of breaks were varied from trial to trial. Break location had four levels, 700, 1200, 1700, and 2200 msec; break duration had three levels, 1, 2, and 3 sec. Thus, a 2 (cue or no cue) x 4 (break location) x 3 (break duration) mixed design was used, with repeated measures on the latter two factors.

The two training sessions were followed by two experimental sessions, either in the cue or in the no-cue condition, depending on the group of participants. The data submitted to analyses were collected in the two experimental sessions, which comprised four 24-trial experimental blocks.

Participants were informed that a tone was presented in all trials. In both cue and no-cue groups, the instructions were to interrupt timing at the beginning of tone presentation and to resume timing at the tone offset. In the cued group, participants were told that they would be forewarned of the break location with a row of asterisks presented on the screen at a constant duration before the tone onset.

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