Restoration of the orienting response to a light by a change in its predictive accuracy

In three experiments the orienting response (OR) to a light was reduced by presenting rats with a serial conditioning schedule in which the light was always followed by a tone, and the tone was intermittently paired with food. The original strength of the OR was then restored by changing the nature of the serial conditioning: the light was followed either by the tone and food, or by nothing. Experiments 1 and 2 demonstrated that this change resulted in an increase in the OR relative to control groups, which continued to receive the original training. Experiment 3 revealed a similar effect using a within-subjects design. A further finding from the first two experiments was that the recovery of the OR was accompanied by an enhancement in the conditionability of the light. Overall, the results suggest that the accuracy with which the light signals the events that immediately follow it is an important determinant of the strength of the OR it elicits.