注意力资源限制与双任务的相互干扰机制

采用心理不应期研究范式, 两个反应时实验检测了注意力资源分配的特征以及双任务的相互干扰机制。每次实验中, 要求被试快速、相继对高低音辨别任务(T1)和Stroop任务(T2)作出选择性反应, T1和T2间采用6种不同的时间间隔(SOA), 以系统考察不同SOA条件下两个任务的反应时走势。结果发现：(1) 在重叠的双任务情境中, T1的中枢加工导致在T2上出现显著的PRP效应, T2的中枢反应选择对T1的反应选择和反应执行加工同样产生显著的影响。SOA以及T2的难度与复杂度实质性地影响了T1的反应选择和反应执行加工。(2) 当两个任务同时需要进行中枢反应选择加工时, 一个任务占用更多的注意资源将导致另一任务获得较少的注意资源, 注意资源量的多寡直接决定了该任务的加工效率。(3) 两个任务的加工相互影响、相互制约, 这种制约机制不仅仅存在于中枢反应选择阶段, 在反应执行阶段仍然存在。     

颜色特征加工任务间的注意瞬脱研究

本研究以两个实验对颜色特征加工任务间的注意瞬脱效应进行探讨。实验一要求被试对首先呈现的两个色块(记忆项)与随后呈现的两个色块(检测项)是否相同进行比较。结果发现,在记忆项与检测项的SOA为220ms的条件下,记忆项加工对认知资源的持续占用使检测项的加工绩效下降。实验二含两个需相继执行的任务(T1和T2),二者均为比较同时呈现在屏幕左右两侧的两色块颜色是否相同。结果发现,对颜色特征的觉察即可产生注意瞬脱效应,其大小及时程与经典的采用字母识别任务的研究获得的注意瞬脱效应相当。上述结果表明,特征搜索的完成需有限认知资源的参与。然而,注意瞬脱过程中,特征加工与需对知觉对象细节信息进行提取的辨别任务(如字母辨别任务)在消耗认知资源的量上并无差别。     

Revealing Language Deficits Following Stroke: The Cost of Doing Two Things at Once

ABSTRACT

The costs of doing two things were assessed for a group of healthy older adults and older adults who were tested at least 6 months after a stroke. A baseline language sample was compared to language samples collected while the participants were performing concurrent motor tasks or selective ignoring tasks. Whereas the healthy older adults showed few costs due to the concurrent task demands, the language samples from the stroke survivors were disrupted by the demands of doing two things at once. The dual task measures reveal long-lasting effects of strokes that were not evident when stroke survivors were assessed using standard clinical tools.     

Continuous Cognitive Tasks Improve Postural Control Compared to Discrete Cognitive Tasks

Research suggests that postural control synergies are sensitive to cognitive manipulations; however, the impact of different types of cognitive tasks on postural control remains inconclusive. The authors examined the effect of discrete and continuous tasks on postural control. Sixteen healthy young adults (M age = 22.7 ± 2.2 years) stood with feet together on a force platform while performing randomly assigned discrete and continuous cognitive tasks. Results demonstrated marked improvements in the area of 95% confidence ellipse and the standard deviation of the center of pressure in the anterior-posterior and medial-lateral directions for continuous compared to discrete tasks. This reinforces the notion that continuous tasks are sufficient in providing less opportunity to consciously attend to postural control, thereby facilitating automatic postural control.     

Evidence for Distinct Attentional Bottlenecks in Attention Switching and Attentional Blink Tasks

E. Weichselgartner and G. A. Sperling (1987), using rapid serial visual presentation (RSVP), estimated that attention could be moved to a new spatial location within 300-400 ms. H. J. Müller and P. M. Rabbit (1989) used a spatial cuing task and found a similar time course for voluntarily redeploying attention. A separate phenomenon known as the attentional blink (AB) also follows a similar time course, yet occurs when participants attend to a single spatial location. The present study found that attention can be shifted more quickly than previously estimated and that part of the deficit observed during searches of spatially distinct RSVP streams is due to an AB. The results support some early and late selection accounts for the temporal dynamics of visual attention and suggest different bottlenecks during visual selection. The implications for visual search and visual processing are discussed.     

注意促进效应依赖于项目-背景的质心间距

近期研究者发现, 在某些条件下增加对第一任务的注意能够提高伴随发生的第二任务的成绩, 并将其命名为注意促进效应。研究者提出双任务交互模型对之进行解释, 认为该效应产生的必要条件是时间上的重叠, 而不受空间距离的影响。基于对这一观点的质疑, 本研究探究了检测项目与背景图片的质心间距对注意促进效应的影响。结果发现, 当目标项位于背景图片中央时(质心间距为0), 表现出注意促进效应; 而当二者分开一定的空间距离时, 出现了注意干扰/抑制效应。由此可见, 项目和背景的质心间距会对注意促进效应产生影响。     

Attentional demands and recall of verbal and color information in action events

Two experiments addressed the influence of secondary task performance at encoding on recall of different features of subject-performed tasks (SPTs) involving objects (e.g., turn the wallet). In Experiment 1, memory for verbs and colors of objects was assessed, with object names serving as cues. In Experiment 2, object and color memory were assessed, with verbs serving as cues. Results from both experiments indicated a greater deterioration of memory performance under divided attention for verbal features than for colors. In addition, intention to remember did not affect performance for any feature in either experiment. The overall pattern of outcome is discussed relative to the view that encoding of verbal features of SPTs is more attention-demanding than encoding of physical task features, such as color.     

注意瞬脱的瓶颈理论

综述了注意瞬脱的瓶颈理论的相关研究。主要包括：（1）高级中枢加工瓶颈形成的两阶段模型、中枢干扰理论、TLC假设和注意的延迟投入假设;（2）目标选择的控制瓶颈形成的输入过滤器与目标模板假说;（3）同时类型系列标记模型。最后从瓶颈理论在整个注意瞬脱理论中的片面性和注意瞬脱的瓶颈理论本身的不完善性两方面剖析了瓶颈理论的局限性     

Spatial Conceptual Influences on the Coordination of Bimanual Actions: When a Dual Task Becomes a Single Task

When the left and right hands produce 2 different rhythms simultaneously, coordination of the hands is difficult unless the rhythms can be integrated into a unified temporal pattern. In the present study, the authors investigated whether a similar account can be applied to the spatial domain. Participants (N = 8) produced a movement trajectory of semicircular form in single-limb and bimanual conditions. In the bimanual tasks, 1 limb moved above the other in the frontal plane. Bimanual unified tasks were constructed so that the spatial paths to be produced by the 2 limbs could be easily conceptualized as parts of a unified circle pattern. Bimanual distinct tasks availed a less obvious spatial pattern that would unify the 2 tasks. Performance of the spatial patterns was more accurate in the unified task, despite similar demands placed on the coordination dynamics between the limbs in the 2 cases (e.g., the phase relations). The authors conclude that a dual task becomes a single task, and interlimb interference is reduced, when the spatial patterns produced by the 2 hands form a geometric arrangement that can be conceptualized as a unified representation.     

双作业的信息编码方式对作业绩效的影响

采用单作业和双作业操作,探讨了不同信息编码方式对双作业操作绩效的影响。实验结果证明：若采用相同的信息编码方式,同时操作的两种作业就会产生相互干扰,降低双作业操作绩效;相反,若同时操作的两种作业采用不同信息编码方式将有效地减小双作业操作的相互干扰,使双作业操作的绩效得到提高。     

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。     

Distraction Affects the Performance of Obstacle Avoidance During Walking

In this study, dual-task interference in obstacle-avoidance tasks during human walking was examined. Ten healthy young adults participated in the experiment. While they were walking on a treadmill, an obstacle suddenly fell on the treadmill in front of their left leg during either midswing, early stance, or late stance of the ipsilateral leg. Participants were instructed to avoid the obstacle, both as a single task and while they were concurrently performing a cognitive secondary task (dual task). Rates of failure, avoidance strategy, and a number of kinematic parameters were studied under both task conditions. When only a short response time was available, rates of failure on the avoidance task were larger during the dual task than during the single task. Smaller crossing swing velocities were found during the dual task as compared with those observed in the single task. The difference in crossing swing velocities was attributable to increased stiffness of the crossing swing limb. The results of the present study indicated that divided attention affects young and healthy individuals' obstacle-avoidance performance during walking.     

Reducing Proactive Interference in Motor Tasks

Abstract

Changing automatized movement patterns often leads to initial performance decrements caused by proactive interference. In this study, we scrutinized whether proactive interference could be reduced by inhibiting the to-be-changed movement pattern by means of a physical movement constraint and verbal inhibition instructions, and whether any of the two interventions may be superior. Skilled typists typed short texts as fast and accurately as possible on a regular QWERTZ keyboard. After baseline measures, a new rule prohibiting the use of the left index finger was introduced. Subsequently, participants took part in either a verbal instruction or an additional motor restriction intervention phase. Results revealed that the original rule change was successful in inducing proactive interference in skilled typists. Most importantly, the two interventions similarly reduced proactive interference both immediately following the rule change and after ten practice sessions. We conclude that reducing proactive interference by means of physical motor restrictions and verbal instructions may be equally effective.     

两种任务下情绪韵律的加工进程

采用ERP技术分别考察了情绪判断和性别判断任务下情绪韵律的加工进程。结果显示：在175-275ms时间段,情绪韵律的加工受实验任务的调节,情绪判断任务下存在效价主效应及负性偏向,愤怒比高兴和中性诱发了更正的P2成分,而性别判断任务则无效价效应。在后期评价加工及反应准备阶段（400-800ms）,两种任务下,愤怒都比高兴和中性诱发了更正的晚成分。上述结果说明,不同情绪韵律的识别存在不同的认知机制,并在一定程度上会受加工任务的调节。     

局部注意干扰效应中的眼动特征

采用眼动追踪范式,本研究通过两个实验探讨局部注意干扰效应（LAI）的注意分配特点和机制。实验一采用搜索时间有限的范式,目标呈现70毫秒后消失,在行为和眼动指标上均发现LAI效应：当两个目标距离较近时,反应时增加,正确率降低,总注视时长增长、注视点增加和眼跳速度加快。实验二增加目标呈现时间至1500毫秒以鼓励搜索,产生了比实验一更强烈的LAI效应,且眼跳速度的模式也有不同,说明增加搜索时间并不利于减轻LAI,从而推断LAI的竞争发生在判断阶段,而非搜索和识别目标阶段。     

Queuing or sharing? A critical evaluation of the single-bottleneck notion

The model of a single central bottleneck for human information processing is critically examined. Most evidence cited in support of the model has been observed within the overlapping tasks paradigm. It is shown here that most findings obtained within that paradigm and that were used to support the model are also consistent with a simple resource model. The most prominent findings are the millisecond-for-millisecond slope at the left of the RT2-SOA curve, the high RT1-RT2 correlation, the additivity of the effects on RT2 of SOA and of the difficulty of selecting R2, and the washout of the effect of S2 discriminability on RT2 in a dual-task condition. In addition, the asymmetry of the effects of the dual-task requirement on RT1 and RT2 can be accounted for by the resource model provided that it assumes uneven allocation of resources, which is quite reasonable in view of the task asymmetry inherent in the demand characteristics of the paradigm. The same is true for two other findings that appear to support the single-bottleneck model-that in the dual-task condition, the demand of the first task affects equally RT1 and RT2 and that its effect on RT1 is the same as the corresponding effect in the single-task condition. Furthermore, the single-bottleneck model is hard to reconcile with a negative slope at the left of the RT1-SOA curve or a positive slope at the left of the IRI-SOA curve, unless augmented by ancillary assumptions that are yet to be substantiated. Representative data were fit by each of the models using its optimal set of parameters. Both models achieved quite good degrees of fit. It is further argued that since the overlapping tasks paradigm is heavily biased in favor of a speedy reaction to the stimulus that appears first, it is nonoptimal for testing the central bottleneck model. Finally, the bottleneck model is examined in terms of other scientific criteria.     

病理性网络使用者对情绪信息的注意偏向研究

探究病理性网络使用者在注意偏向上是否存在情绪干扰。采用情绪图-词Stroop范式对病理性网络使用者与正常网络使用者进行比较研究。结果表明(1)病理性网络使用者与正常网络使用者相比,有对情绪词语有更加突出的反应延迟特点,表现出了明显的情绪干扰。(2)病理性网络使用者与正常网络使用者相比,具有更多的负性认知偏向。(3)病理性网络使用者与正常网络使用者相比,在图词不一致的情况下有更多的反应延迟存在。     

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。     

探测任务知觉负荷对注意促进效应的影响

双任务交互作用模型认为探测任务知觉负荷对注意促进效应(the attentional boost effect,ABE)不存在影响。基于对这一观点的质疑,本研究以场景图片为实验材料,结合学习-测验经典范式和目标探测任务,实验一探讨高、低知觉负荷探测任务对ABE的影响;实验二验证探测任务知觉负荷对ABE的影响是否受探测目标与非目标相似性调节,进一步验证双任务交互作用模型的观点。结果发现,低知觉负荷探测任务中存在ABE,但高知觉负荷探测任务中却不存在;探测目标与非目标不相似条件下的高知觉负荷探测任务中不存在ABE,但相似条件下的高知觉负荷探测任务中依然存在。由此可见,探测任务知觉负荷对ABE存在影响,且这一影响受探测目标与非目标相似性调节,双任务交互作用模型的观点不合理。