Acquisition and retention of habituation as a function of intertrial interval duration during training in the blowfly

The influence of the duration of the interval between successive stimulations during habituation training on the dynamics of motor response decrement and its retention over time has been studied in the blowfly, Calliphora vomitoria . The intertrial interval (ITI) duration during training was either 7, 15, 30, 60 or 120 seconds. After a rest period of 30 minutes, a second session was given with the same ITI duration of 30 seconds for all groups. The response decrement observed during training is faster the longer the ITI duration. At the end of this session, the lower response level is reached with an ITI of 60 seconds. After the rest period, the lower responsiveness is observed in the animals which have been trained with the longer ITI. These results are discussed with reference to the dual-process theory of habituation, which can account for the results obtained during training, and memory-centered models to interpret the influence of ITI duration on retention performance.