A Swap Methodology Applied to Implicit Sequence Learning

Two experiments used a methodology in which elements in a serially presented sequence of 5 elements were randomly reinforced during training. To assess what was learned, elements were systematically swapped with each other during testing. The usual outcome measures in implicit sequence learning of this type are either a random test in which elements are disarrayed, or pairwise tests in which subjects choose between two elements. Each of these methods possesses shortcomings. The random test is a blunt measure, whereas pairwise tests disrupt the usual flow of elements in a serial sequence. Pairwise tests also present the problem of how to reinforce subjects during testing in a way that doesn't violate the delivery of reinforcement on a random basis. The swaps methodology is more targeted in that only two elements exchange ordinal positions. The procedure is at once more precise than the standard random test and is less disruptive to the flow of an implicit sequence than are pairwise tests. Results of both experiments indicated that the swaps manipulation was successful in disrupting latencies. Regression analyses indicated that subjects learned something about the ordinal position of elements. The separate analysis of symbolic distance versus spatial distance in Experiment 2 provided evidence, but only provisional evidence, of a symbolic distance effect in implicit learning.