Successiveness discrimination: Two models

Two models for successiveness discrimination, an attention-switching model and a duration-discrimination model, are described. Data are reported from a forced-choice successiveness discrimination task in which the standard stimulus assumed one of three values during a session. Of major interest is the ability of the models to account for the absence of observed variation in performance with changes in value of the standard. Conventional signal detection-type models or discrete state models would be unable to account for the data.