Human sequence learning under incidental and intentional conditions.

Abstract

This research explored the role that dissociable associative learning and hypothesis-testing processes may play in human sequence learning. Two 2-choice serial reaction time (SRT) tasks were conducted, 1 under incidental conditions and the other under intentional conditions. In both cases an experimental group was trained on 4 subsequences (i.e., XXX, XYY, YYX, and YXY). To control for sequential effects, sequence learning was assayed by comparing their performance to a control group that had been trained on a pseudorandom ordering, during a test phase in which both groups experienced effectively the same trial order. Under incidental conditions participants demonstrated learning of the subsequences that ended in an alternation, but not of those that ended in a repetition. In contrast, under intentional conditions XXX showed the greatest evidence of learning. This dissociation is explained using a 2-process model of learning, with an associative process (the augmented simple recurrent network [SRN]) capturing the incidental pattern, and a rule-based process explaining the advantage for XXX under intentional conditions.