title: Arousal modulates temporal preparation under increased time uncertainty: Evidence from higher-order sequential foreperiod effects.
abstract: When the foreperiod (FP) is unpredictably varied in reaction-time tasks, responses are slow at short but fast at long FPs (variable-FP effect), and further vary asymmetrically as a function of FP sequence (sequential FP effect). A trace-conditioning model attributes these phenomena to time-related associative learning, while a dual-process model views them as resulting from combined effects of strategic preparation and trial-to-trial changes in arousal. Sometimes, responses are slower in long-long than in short-long FP sequences. This pattern is not predicted from the trace-conditioning account, since FP repetitions should speed up, rather than slow down, responses (due to reinforcement). The effect, however, might indicate the contribution of arousal, which according to the dual-process model, is heightened after a short FP(n-1) but decreased after a long FP(n-1). In five experiments, we examined higher-order sequential FP effects on performance, with a particular emphasis on analyzing performance in long-FP(n) trials as a function of FP length in the two preceding trials, varying temporal FP context (i.e. average FP length) and reaction mode (simple vs. choice reaction). Slower responses in long-long-long (compared with short-short-long) FP sequences were not found within a short-FP context (Exps. 1 & 2) but clearly emerged within a long-FP context (Exps. 3-5). This pattern supports the notion that transient arousal changes contribute to sequential performance effects in variable-FP tasks, in line with the dual-process account of temporal preparation.
authors.affiliation: Evolutionary Cognition, University of Tübingen, Germany. michael.steinborn@uni-tuebingen.de
authors.forename: Michael B
authors.initials: MB
authors.lastname: Steinborn
authors.forename: Robert
authors.initials: R
authors.lastname: Langner
mesh_terms: D000293:Adolescent; D000328:Adult; D001143:Arousal / Q000502:physiology*; D001288:Attention / Q000502:physiology*; D002755:Choice Behavior / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D011597:Psychomotor Performance / Q000502:physiology; D011930:Reaction Time / Q000502:physiology; D013998:Time Perception / Q000502:physiology*; D035501:Uncertainty