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Miller, Patterson, and Ulrich (1998) introduced a jackknife-based method for measuring the differences between two conditions in the onset latencies of the lateralized readiness potential (LRP). The present paper generalizes such jackknife-based methods to factorial experiments with any combination of within- and between subjects factors. Specifically, we(More)
Within the context of the psychological refractory period (PRP) paradigm, we developed a general theoretical framework for deciding when it is more efficient to process two tasks in serial and when it is more efficient to process them in parallel. This analysis suggests that a serial mode is more efficient than a parallel mode under a wide variety of(More)
In divided-attention tasks, responses are faster when two target stimuli are presented, and thus one is redundant, than when only a single target stimulus is presented. Raab (1962) suggested an account of this redundant-targets effect in terms of a race model in which the response to redundant target stimuli is initiated by the faster of two separate target(More)
OBJECTIVE This study used reaction time (RT) as an objective marker of cognitive fatigue and fatigability in patients with multiple sclerosis (MS). METHOD RT was measured in fifteen healthy controls and in thirty MS patients with cognitive fatigue identified with the Fatigue Scale for Motor and Cognitive Function (FSMC). Secondary fatigue was excluded(More)
Four experiments examined effects of bimodal stimulation on response force (RF) in addition to reaction time (RT). In a divided-attention task (Experiments 1 to 3), subjects were asked for a speeded response to either a visual or an auditory signal. In unimodal signal trials, either a visual or an auditory signal was presented alone, and in(More)
The metaphoric mapping theory suggests that abstract concepts, like time, are represented in terms of concrete dimensions such as space. This theory receives support from several lines of research ranging from psychophysics to linguistics and cultural studies; especially strong support comes from recent response time studies. These studies have reported(More)
Tse et al. (Percept Psychophys 66:1171-1189, 2004) reported that participants tend to overestimate the duration of an oddball stimulus. The size of this effect was much larger than the one reported by Ulrich et al. (Psychol Res 70:77-87, 2006). More crucially, the effect in the study of Tse et al. already emerged at short standard durations, arguing against(More)
STUDY OBJECTIVE To estimate the 12-month prevalence of cognitive-enhancing drug use. DESIGN Paper-and-pencil questionnaire that used the randomized response technique. SETTING University in Mainz, Germany. PARTICIPANTS A total of 2569 university students who completed the questionnaire. MEASUREMENTS AND MAIN RESULTS An anonymous, specialized(More)
In simple, go/no-go, and choice reaction time (RT) tasks, responses are faster to two redundant targets than to a single target. This redundancy gain has been explained in terms of a race model assuming that whichever target is processed faster determines RT (Raab, 1962). Miller (1982) presented a race model inequality to test the race model by comparing(More)
BACKGROUND Anabolic ergogenic substance use, in particular the use of anabolic androgenic steroids, is a serious problem in general. Nevertheless, it is subject to debate whether ergogenic substance users exhibit similar features as multiple substance users or whether they constitute a discrete group. METHODS One thousand eight hundred and two(More)