International Journal of Comparative Psychology

Evidence from serial pattern learning research has been used to support the controversial claim that rats detect, encode, and use abstract rules. To understand why the evidence indicates that rats’ “rules”are abstract, we examine the basis of “pattern structure” in sequential tasks, how rats respond to pattern structure in highly-organized sequences, the role of “rules” in rats’ representation of patterned sequences, and the notion that rats’ “rules” differ from generalization. We show that “pattern structure” reflects systematic abstractions from stimuli that can be described by abstract relationships,that rats are flexible in representing sequential patterns, that rats use “rules” along with other forms of representation concurrently in serial pattern learning, and that associative/generalization models do not always predict rats’ “rule-governed” behavior. Both behavioral and neurobiological evidence suggest that “rules” are not simply emergent properties of associative networks, that instead rule abstraction and associative processes are mediated by separate concurrently active systems in serial pattern learning. It is not known how “rules” are instantiated in the nervous system, and a key problem at a more molar level of analysis is what determines the output of multiple concurrently active cognitive systems in serial pattern learning.