Rate-change effects during a pre-schedule-change stimulus.

The team used a simple lab setup. Pigeons pecked a key for food on a VI schedule.

A red light came on three minutes before the schedule changed. The researchers counted pecks during this warning and right before it.

They wanted to know if the birds changed speed when they got the heads-up.

The birds did shift their pecking speed once the red light appeared.

The paper does not say if the speed went up or down, only that it moved.

Pliskoff et al. (1978) later showed the same kind of rate jump right after birds switch between two VI keys. Their 2-second changeover delay kept the burst going for three seconds.

McLean et al. (1981) ran multiple-schedule sessions and saw the biggest rate swings just after each new component began. Both teams built on the 1961 warning effect by pinning down when the swing starts and how long it lasts.

Schaal et al. (1990) used longer pre-reinforcement signals and also saw higher peck rates. Their work widens the 1961 finding: any stimulus that fills the gap before a change can nudge responding.

Your learners can feel the same nudge. Before you move from easy to hard tasks, give a brief visual or verbal cue. Watch the work pace for a few seconds. If it jumps too high or drops, adjust the next schedule or add a brief pause. These tiny timing tweaks can smooth transitions and keep the session calm.