Poorer performance in conditions involving task repetition within blocks of mixed tasks relative to task repetition within blocks of single task is called mixing cost (MC). In 2 experiments exploring 2 hypotheses regarding the origins of MC, participants either switched between cued shape and color tasks, or they performed them as single tasks. Experiment 1 supported the hypothesis that mixed-tasks trials require the resolution of task ambiguity by showing that MC existed only with ambiguous stimuli that afforded both tasks and not with unambiguous stimuli affording only 1 task. Experiment 2 failed to support the hypothesis that holding multiple task sets in working memory (WM) generates MC by showing that systematic manipulation of the number of stimulus-response rules in WM did not affect MC. The results emphasize the role of competition management between task sets during task control.Keywords: task switching, switching cost, mixing cost, task ambiguity, working memory One of the prominent questions in psychological research concerns behavior control. Whereas the behaviorists' tradition has ascribed most behavioral control to the environment, recent cognitive theorists have emphasized more internally driven, top-down forms of control. This idea of cognitive control involves concepts such as goal-directed behavior, initiation, executive control processes, and so forth. A key concept in the context of top-down control is the task-set. According to Rogers and Monsell (1995), the control of task-sets is manifested in the ability to configure processing resources to perform one rather than another of the many cognitive tasks that a stimulus affords.A common paradigm for studying task-set control is the taskswitching paradigm. In the original version of this paradigm, performance in blocks of trials in which a task is repeated is compared with performance in blocks in which the participants switch between two different tasks (Allport, Styles, & Hsieh, 1994;Jersild, 1927;Spector & Biederman, 1976). More recent studies have used a modified paradigm that makes it possible to contrast task-switch trials and task-repetition trials within blocks of mixed tasks (e.g., De Jong, 1995bGoschke, 2000;Mayr & Keele, 2000;Meiran, 1996;Rogers & Monsell, 1995). In most cases, switching tasks is accompanied by a robust performance cost, seen both in reaction time (RT) and error rates, indicating switch cost.A recent conceptualization that incorporates knowledge from the variety of task-switching paradigms elaborates and sharpens the understanding of the switch mechanisms by differentiating between several cost components. The difference in performance between switch and repetition trials (in mixed-tasks blocks) is termed switching cost, and the difference between repetition trials (in mixed-tasks blocks) and single-task trials (in pure blocks) is termed mixing cost (

To switch from one cognitive task to another is thought to rely on additional control effort being indicated by performance costs relative to repeating the same task. This switch cost can be reduced by advance task preparation. In the present experiment the nature of advance preparation was investigated by comparing a situation where an explicit task cue was presented 2000 ms in advance of the target stimulus (CTI-2000) with a situation where cue and target were presented in close succession (CTI-100). We mapped the blood-oxygenation-leveldependent (BOLD) activation correlates of switch-related control effort and advance task preparation to test alternative explanations why advance preparation is reducing switch costs. A previously reported control-related cortical network of frontal and parietal brain areas emerged that was more strongly activated for switching between tasks. However, this was true exclusively for CTI-100 where no advance task preparation was possible. At CTI-2000 these same brain areas were equally engaged in both switch and repeat trials. For some of these areas, this common activation was time-locked to the presentation of both the cue as well as the target. Other areas were exclusively associated with target processing. The overall pattern of results suggests that advance task preparation is a common process of pre-activating (cue-locked activation) the currently relevant task set which does not face interference from a persisting N − 1 task set. During target processing the same brain areas are re-engaged (subsequent target-locked activation) to apply the pre-activated task set. Though being common to repeat and switch trials, advance preparation has a differential benefit for switch trials. This is because the instructed task set has time to settle into a stable state, thus becoming resistant against disruption from the previous task set, which is retrieved by the current target stimulus.

MOR is a reliable tool for measuring non-cognitive attributes in medical school candidates. It has high content and face validity. Furthermore, its implementation conveys the importance of maintaining humanist characteristics in the medical profession to students and faculty staff.

Simulation-based training can be incorporated into the risk management process and can contribute to patient safety practice.