Serial-pattern learning in mice: Pattern structure and phrasing

In two experiments, mice learned 24-element serial patterns. In Experiment 1, patterns either were perfectly structured or had a single violation elem ent and were either phrased by temporal pauses or unphrased. In Experiment 2, the same violation pattern of Experiment 1 was phrased by temporal cues, visual cues, or a combination of the two. For mice, as for rats and humans in earlier studies, pattern structure predicted pattern learning difficult y and also the nature and relative frequency of errors. Mice, like rats and humans, also found a violation element especially difficult to learn and a t that point in the pattern made errors consistent with the structure of th e remainder of the pattern. However, in both experiments, phrasing interfer ed with responding correctly on the element after the phrasing cue. In a th ird experiment, mice were able to use temporal intervals and, to a lesser d egree, visual stimuli as discriminative cues to control spatial responses i n the same apparatus used in earlier studies. The results support the view that mice are sensitive to pattern organization but may have difficulty usi ng phrasing cues in the context of serial patterns.