双作业信息输入通道对作业绩效的影响

采用单作业和双作业操作,探讨了不同信息输入通道对双作业操作绩效的影响。实验结果证明：若采用相同的信息输入通道,同时操作的两种作业就会产生相互干扰,降低操作绩效;相反,若采用不同信息输入通道,双作业之间的相互干扰将减小,作业绩效得到提高。     

不同反应方式对双作业操作信息干扰的影响

本研究采用单作业双作业操作,探讨了不同反应方式对双作业操作信息干扰的影响。实验结果证明;若采用相同的反应方式,同时操作的两种作业就会产生相互干扰,降低作业绩效;相反,若采用不同反应方式将减小双作业操作的相互干扰,提高双作业操作绩效。     

双重作业的颜色编码方式对作业绩效的影响

研究探讨了不同颜色编码方式对双重任务操作绩效的影响。实验结果证明：若采用同类颜色编码方式,同时操作的两种作业就会产生结构限制,降低双重任务操作绩效;相反,若采用异常颜色编码方式,将有效地减少双重任务操作的结构限制,使双重任务的操作绩效得到提高。     

结果冲突与作业难度对双重作业绩效的影响

运用单作业和双作业操作探讨结果冲突与作业难度对双重作业绩效的影响。结果表明：（１）信息干扰对双作业操作有着明显的影响。信息干扰越大,结果冲突效应越大,双作业操作绩效越差。（２）作业难度对双作业绩效有明显影响。作业难度越大,双作业操作绩效越差。根据实验结果,本研究提出了双因素假设：信息干扰和资源竞争是影响双作业操作绩效的两个主要因素。     

结构限制和信息干扰对双重作业绩效的影响

研究通过改变双重任务呈现的间隔时间来探讨结构限制与信息干扰对双重任务操作绩效的影响。实验结果表明：(1)两种作业呈现的间隔时间对双重任务操作绩效有明显的影响。间隔时间越大,双重任务的作业绩效越高。(2)信息干扰对双重任务的操作有明显的影响。信息干扰越大,双重任务的操作绩效越差。(3)两个作业呈现的间隔时间不同并不影响信息干扰对双重任务操作绩效的作用。根据实验结果,该研究提出了三因素假设：结构限制、信息干扰和资源竞争是影响双重任务操作绩效的三个主要因素。     

结构限制和作业难度对双重作业绩效的影响

通过对不同双重任务的呈现间隔时间和不同任务难度的双重任务的操作研究,探讨了结构限制与资源竞争对双重任务操作绩效的影响。实验结果表明：(1)两种作业呈现的间隔时间对双重任务操作绩效有明显的影响。间隔时间越大,双重任务的作业绩效越好。(2)作业难度对双重任务的操作有明显的影响。作业难度越大,双重任务的操作绩效越差。(3)两个作业呈现的间隔时间不同并不影响作业难度对双重任务操作绩效的作用。本研究的实验结果进一步证实了双重任务操作的三因素假设：结构限制、信息干扰和资源竞争是影响双重任务操作绩效的三个独立的原因。     

作业中断对任务绩效的影响及心理疲劳的调节作用

作业中断会对中断后行为绩效产生影响,探讨不同疲劳状态下中断对作业绩效影响的认知机制将有助于完善和发展中断的认知理论。本研究采用事件相关电位(ERP),通过在不同心理疲劳状态下执行数学题任务中断、暂停中断和不中断的空间2-back任务,结合行为数据和ERPs结果,分析作业中断对任务绩效的影响以及心理疲劳在其中的调节作用。实验结果发现,中断后诱发的P200和P300振幅显著提高,作业中断使得主任务的注意力资源下降,任务中断的无关信息干扰了主任务工作记忆,而疲劳状态则进一步加剧了中断对注意资源、工作记忆及行为绩效的负面效应。本研究在揭示作业中断认知过程及疲劳对其影响机理的同时,也支持了中断的目标记忆模型。     

选择反应作业中的反应组织

通过2-选择反应作业的两个反应复杂度不对称（不等）实验因素考察反应组织,发现在同一作业中无反应复杂度效应,而作业之间反应复杂度效应显著。这提示选择反应是选择已完成组织的反应,而不是实时地进行反应动作组织,进而引入动作模块的概念。即把反应组织视为选择动作模块过程。其实际意义是,在操作界面的优化设计中,要提高一组同时可选择操作R中的某一种操作Ri(R∈Ri|i=1,2,…,n）的绩效,其有效途径是应降低这一组操作R的平均复杂度;如果只降低Ri的复杂度,要提高其绩效收效甚微。     

团队作业与团队互动两类共享心智模型的发展特征

共享心智模型指团队成员关于团队作业、策略、团队情境、团队互动等的共同的知识结构,根据内容不同可以分为团队作业模型和团队互动模型两类。该研究通过实验室实验探讨两类共享心智模型的发展特征。132名大学生组成44个3人团队,随机分为团队绩效反馈组和无团队绩效反馈组。采用相似性评定法在团队执行作业前、中、后三次测量两类共享心智模型。结果发现：（1）共享心智模型随团队运作时间增加而发展;（2）团队互动模型形成和发展的难度高于团队作业模型;（3）团队绩效反馈对两类心智模型发展的作用不同,反馈加速了团队作业模型的发展速度,但却是团队互动模型能否得以发展的决定性因素。两类共享心智模型的不同发展特征应归因于两者特异性高低的不同     

作业绩效和关系绩效

关系绩效是最近抛起的一个热点。该对关系绩效的提出,作业绩效和关系绩效划分的根据,以及绩效可以分为作业绩效和关系绩效、可以用不同的预测源预测作业绩效和关系绩效的证明的有关献进行了回顾。并从中获得了几点启示。     

Working memory capacity does not always promote dual-task motor performance: The case of juggling in soccer

The aim of this research was to refine our understanding of the role of working memory capacity (WMC) on motor performances that require attentional control in dual-task situations. Three studies were carried out on soccer players. Each participant had to perform a juggling task in both normal and dual-task conditions. In Study 1, the interfering task was a mental calculation test performed under time pressure (strong cognitive load). In Study 2, the interfering task was a count-down test (low cognitive load). In Study 3 an intra-individual design in which participants perform dual-tasks increasingly complex has been proposed. Results showed a positive relationship between participants’ WMC and their dual-task motor performance when the cognitive load was low and a negative relationship when the cognitive load was high. This paper highlights the role of the WMC in the activation of different modes of processing and its importance on the performance in dual-task.     

A neuropsychological assessment of dual-task costs in closed-head injury patients using Cohen’s effect size estimation method

A test of whether patients suffering from a severe closed-head injury (CHI) were affected by disproportionate dual-task costs compared to those of healthy control participants was carried out through a direct comparison of CHI effects on dual-task (psychological refractory period, or PRP) performance and on single-task performance. In the dual-task condition of the present experiment, independent choice-responses were required to two sequential stimuli presented at a variable stimulus onset asynchrony (SOA). A significant delay of the reaction time (RT) to the second stimulus was reported by both CHI patients and controls at short (SOA) compared to long SOA, i.e., a PRP effect. The PRP effect was more pronounced for CHI patients than controls. In the single-task condition, a single choice-response was required to a stimulus presented in isolation. The RT produced by CHI patients in the single-task paradigm was longer than the RT produced by controls. CHI effects on dual-task performance and on single-task performance were compared following (1) their transformation into Cohen’s ds, and (2) the application of a correction algorithm taking into account the different reliability of single-task and dual-task measures. The analysis of Cohen’s ds revealed that CHI effects on performance were, if anything, smaller in the dual-task condition than in the single-task condition. The results imply that CHI patient’s slower responding in single- and dual-task performance reflects a single common cause—slowing of the central processing.     

Age- and practice-related influences on dual-task costs and compensation mechanisms under optimal conditions of dual-task performance

Impaired dual-task performance in younger and older adults can be improved with practice. Optimal conditions even allow for a (near) elimination of this impairment in younger adults. However, practice effects under these conditions in older adults are unknown. Further, it is open, how changed task scheduling and/ or the acquisition of task coordination skills affect the temporal overlap of two tasks in different age groups; this overlap indicate the involvement of these practice-related mechanisms to compensate for impaired dual-task performance. In a dual-task situation of Schumacher et al. (2001 , Psychological Science, 12, 230) including optimal conditions for dual-task performance, both younger and older adults were able to achieve an improvement in dual-task performance with 8 practice sessions to the same degree. The temporal task overlap changed similarly in both age groups during these sessions demonstrating a similar degree of the involvement of compensation mechanisms in younger and older adults. At the end of practice, however, we showed that older adults do not achieve the same optimized dual-task performance level of younger adults.     

Age-related differences in executive control of working memory

In two experiments, we used dual-task methodology to assess the effect of aging on executive control of working memory. We hypothesized that (1) age-related dual-task costs would be observed even when individual tasks represent different perceptual modalities; (2) age would modulate the effect of increased temporal overlap on dual-task performance; and (3) the vulnerability of specific memory mechanisms to interference would be age related. We found that aging was associated with disproportionate dual-task costs that increased when extending the overlap between individual tasks. The effect of interference with encoding, and arguably output, was disproportionately larger in old than in young individuals. Ensuring that individual tasks represent different perceptual modalities is important but insufficient when using dual-task methodology to assess the effect of aging on executive function. The degree of temporal overlap between individual tasks and the sensitivity of specific memory operations to interference should be considered, as well.     

Task-set inertia and memory-consolidation bottleneck in dual tasks

Three dual-task experiments examined the influence of processing a briefly presented visual object for deferred verbal report on performance in an unrelated auditory-manual reaction time (RT) task. RT was increased at short stimulus-onset asynchronies (SOAs) relative to long SOAs, showing that memory consolidation processes can produce a functional processing bottleneck in dual-task performance. In addition, the experiments manipulated the spatial compatibility of the orientation of the visual object and the side of the speeded manual response. This cross-task compatibility produced relative RT benefits only when the instruction for the visual task emphasized overlap at the level of response codes across the task sets (Experiment 1). However, once the effective task set was in place, it continued to produce cross-task compatibility effects even in single-task situations (“ignore” trials in Experiment 2) and when instructions for the visual task did not explicitly require spatial coding of object orientation (Experiment 3). Taken together, the data suggest a considerable degree of task-set inertia in dual-task performance, which is also reinforced by finding costs of switching task sequences (e.g., AC → BC vs. BC → BC) in Experiment 3.     

The role of input and output modality pairings in dual-task performance: evidence for content-dependent central interference

Recent debate regarding dual-task performance has focused on whether costs result from limitations in central capacity, and whether central operations can be performed in parallel. While these questions are controversial, the dominant models of dual-task performance share the assumption that central operations are generic--that is, their interactions are independent of stimulus and response modalities. To examine these issues, we conducted a series of dual-task experiments with different input and output modality pairings. One condition combined a visual-manual task with an auditory-vocal task, and the other condition reversed the input-output pairings, combining a visual-vocal task with an auditory-manual task. Input/output modality pairings proved to be a key factor; throughout practice, dual-task costs were generally more than twice as large with visual-vocal/auditory-manual tasks than with the opposite arrangement of modalities (Experiments 1 and 2). These differences could be explained neither by competition for peripheral resources nor by differences in single-task response times (Experiment 3). Moreover, the persistent dual-task costs did not appear to stem from a central bottleneck. Contrary to the dominant models of dual-task performance, we propose that central interference between tasks depends not just on the duration of central operations, nor just strategic adaptation, but also on the content of those operations. Implications for structural and strategic accounts of dual-task interference are discussed.