Much of Stewart Hulse's career was spent analyzing how animals can extract patterned information from sequences of stimuli. Yet an additional form of information contained in a sequence may be the number of times different elements occurred. Experiments that required numerical discrimination between different stimulus items presented in sequence…

Three experiments examined the processes mediating rat serial pattern learning for rule-consistent versus rule-violating pattern elements ("violation elements"). In all three experiments, rats were trained to press retractable levers in a circular array in a specific sequence for brain-stimulation reward (BSR). Experiment 1 examined the role of…