title: Secondary-task effects on sequence learning.
abstract: With a repeated sequence of stimuli, performance in a serial reaction-time task improves more than with a random sequence. The difference has been taken as a measure of implicit sequence learning. Implicit sequence learning is impaired when a secondary task is added to the serial RT task. In the first experiment, secondary-task effects on different types of sequences were studied to test the hypothesis that the learning of unique sequences (where each sequence element has a unique relation to the following one) is not impaired by the secondary task, while the learning of ambiguous sequences is. The sequences were random up to a certain order of sequential dependencies, where they became deterministic. Contrary to the hypothesis, secondary-task effects on the learning of unique sequences were as strong or stronger than such effects on the learning of ambiguous sequences. In the second experiment a hybrid sequence (with unique as well as ambiguous transitions) was used with different secondary tasks. A visuo-spatial and a verbal memory task did not interfere with the learning of the sequence, but interference was observed with an auditory go/no-go task in which high- and low-pitched tones were presented after each manual response and a foot pedal had to be pressed in response to high-pitched tones. Thus, interference seems to be specific to certain secondary tasks and may be related to memory processes (but most likely not to visuo-spatial and verbal memory) or to the organizations of sequences, consistent with previous suggestions.
authors.affiliation: Institut für Arbeitsphysiologie an der Universität Dortmund, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Heuer
authors.forename: V
authors.initials: V
authors.lastname: Schmidtke
mesh_terms: D000293:Adolescent; D000328:Adult; D001288:Attention; D005260:Female; D005793:Generalization, Psychological; D006801:Humans; D008297:Male; D010364:Pattern Recognition, Visual; D010897:Pitch Discrimination; D011601:Psychophysics; D011930:Reaction Time; D012691:Serial Learning; D014706:Verbal Learning