言语工作记忆的保持对时间知觉的影响*

采用工作记忆和时间判断的双任务范式,探讨了言语工作记忆的保持过程对时间知觉的影响。研究中操作记忆负荷和任务之间的时间间隔(ISI:记忆刺激消失到时间判断任务开始之间的时间间隔)。结果发现,记忆负荷越大,知觉到的时间越短,韦伯比例越低,反应时间越长;ISI越短,知觉到的时间变短,反应时间越长,这表明知觉时间和反应决策是一致的,不存在累加时间和反应判断之间的trade-off。但是记忆负荷和ISI的交互作用不显著。结果表明记忆负荷和ISI以不同的方式影响时间判断,言语工作记忆的保持和时间加工共享工作记忆资源。     

基于客体工作记忆内容的保持对时间判断的影响

本研究通过操作工作记忆内容的有效性,探讨了记忆内容的保持对时间判断的影响。采用不规则的客体作为实验材料,使时间任务中的刺激与工作记忆内容匹配或不匹配。实验1采用工作记忆和时间判断的双任务范式,要求被试首先记忆一个客体,然后在每个试次的最后判断测试刺激是否与记忆项相同。在延迟阶段,被试判断连续出现的两个刺激的时距哪个更长（或更短）。实验2中,要求被试忽略第一个刺激,仅完成时间判断任务。结果发现,相比单任务的计时,双任务条件下,工作记忆内容的保持延长了时间判断的时间。而且,在记忆匹配和知觉匹配条件下,匹配刺激呈现的时间越长,正确率越低,反应时越长。这说明记忆内容的保持增加了决策的难度,工作记忆内容对时间判断的可能是由记忆内容引起的注意定向造成的。     

知觉表征精度对工作记忆中抑制干扰能力的影响

工作记忆的容量十分有限,需要选择性地抑制与目标无关信息的干扰,工作记忆容量高的个体,其抑制干扰的能力也更强。本研究采用带有不同形状干扰刺激的色块颜色回忆任务考察干扰对工作记忆容量和表征精度的影响,结果发现,当负荷超出工作记忆容量范围时,干扰减少了记忆所能表征客体的个数;当负荷在工作记忆容量范围内时,干扰降低了记忆中表征客体的精度。更进一步,研究采用独立的知觉任务来测量知觉表征的精度,并探讨作为信息加工的初始阶段的知觉表征如何影响工作记忆加工过程中抑制干扰的能力。将实验中收集的48名有效被试按照知觉表征精度的高低平均分为两组,结果发现上述干扰效应主要表现在知觉表征精度较低的组中,并且该组中知觉表征精度越高的个体,其工作记忆抑制干扰的能力也越强。本研究为实践中通过知觉训练来提升工作记忆的抑制干扰能力提供了理论指导。     

视觉工作记忆参与融景知觉

融景知觉现象是指观察者任意时刻虽然只能观察到部分刺激模式,却能基于部分刺激模式形成完整知觉。完成融景知觉的关键在于需要将时间序列上的信息进行整合。根据视知觉与视觉工作记忆动态交互模型,完成信息整合需视觉工作记忆的参与。然而以往研究均关注融景现象的知觉加工特性,尚未涉及视觉工作记忆在该现象中的作用机制。笔者采用双任务范式,要求被试完成规则或不规则刺激模式的融景知觉,同时操纵工作记忆负荷,以考察记忆负荷对融景知觉的影响。结果发现,高记忆负荷显著降低不规则刺激的融景知觉绩效(实验一);且该效应并非由记忆负荷对融景刺激维持阶段的影响所致(实验二)。上述结果说明,至少对不规则图形的融景知觉需要视觉工作记忆参与。     

基于客体工作记忆的保持对时间判断的影响（英文）

本研究探讨工作记忆内容的保持能否影响时间判断,采用难以用言语编码和保持的抽象客体作为刺激材料,操作记忆内容与时间任务中刺激的关联程度。实验1将工作记忆中的变化觉察范式和时间判断任务结合,具体来讲,要求被试首先记忆一个客体,然后在每个trial的最后判断测试刺激是否与记忆项相同;在延迟阶段,被试完成时间判断任务,即判断相继出现的两个刺激的时距哪个更长(或更短)。记忆匹配条件下,时间任务中的一个刺激与记忆内容完全相同,相应的另一个刺激与记忆内容在形状和颜色上都不同,记忆匹配和记忆不匹配各占一半。匹配刺激先短后长、先长后短的顺序在被试内充分平衡;记忆不匹配条件下,时间任务中的两个刺激均与记忆项无关。结果发现,记忆匹配刺激不存在顺序效应;相比无记忆匹配条件,记忆匹配延长了时间判断的时间;进一步分析发现记忆匹配刺激与长时距对应时,正确率更低,反应时更长。为了进一步探讨实验1的结果是由对记忆内容的保持造成的,还是由刺激的重复出现造成的,实验2要求被试忽略第一个刺激,仅完成时间判断任务。结果发现,知觉匹配和知觉不匹配条件在时间判断的正确率和反应时上都无显著差异。研究说明记忆内容的保持引起了注意定向,影响了人们对时间信息的判断和决策。     

知觉负载和线索位置对视觉选择性注意的影响

采用线索范式,以汉语双字词为材料,探讨了不同工作记忆负荷条件下知觉负载、线索位置对视觉选择性注意的影响.结果表明:(1)线索位置影响被试对目标的加工,前线索条件下被试对目标的加工更为精细;(2)知觉负载对选择性注意的影响受到工作记忆的调节.高工作记忆负荷条件下,高知觉负载条件下的反应时显著短于低知觉负载条件;而在低工作记忆负荷条件下,不同知觉负载条件下的反应时差异不显著.     

工作记忆与知觉负载对工作记忆表征引导注意的调节

本研究采用4个眼动实验探讨不同知觉负载条件下的视觉搜索任务中工作记忆负载对基于工作记忆表征的注意引导效应的影响。实验1和实验3采用低知觉负载的视觉搜索任务,结果在视觉工作记忆负载为1和2时观察到了显著的注意引导效应,但当负载增加到4时注意引导效应消失了;实验2和实验4采用高知觉负载的视觉搜索任务,结果发现注意引导效应在工作记忆负载增加到2时就已经消失了。上述结果表明:工作记忆负载和知觉负载都能够通过调控认知资源的方式来影响工作记忆表征对注意的引导,当认知资源充足时,工作记忆能够同时保持多个记忆表征对视觉注意的引导。     

工作记忆内容对无意视盲的改善作用

无意视盲是注意捕获失败的一种现象.研究发现:工作记忆内容对视觉注意的引导可以影响视觉注意的捕获.本研究以此为基础探讨了工作记忆内容能否影响无意视盲.本研究采用了静态无意视盲典型范式,通过两个实验分别探讨了工作记忆对无意视盲的引导作用以及在不同知觉负荷下引导作用的自动性,进而研究工作记忆内容对无意视盲的改善作用.实验1结果表明,当非期望刺激与工作记忆内容属于同一类别时,对非期望刺激的觉察率显著高于当非期望刺激与工作记忆内容不属于同一类别的情况,说明在纯语义的水平上工作记忆内容可以引导视觉注意捕获,进而改善无意视盲.实验2发现,当知觉负荷由低到高变化时,非期望刺激与工作记忆内容同类属时,觉察率无显著变化,说明工作记忆内容对无意视盲引导不受知觉负荷的调节,是一种自动化的过程.     

工作记忆的存储时间及目标时距对时间知觉的影响

本研究操作记忆信息与计时开始之间的时间间隔（ISI）和目标时距,探讨工作记忆影响时间判断的灵活性。被试首先记忆一个客体,然后在每个trial的最后判断测试刺激是否与记忆项相同;在延迟阶段,被试完成时间判断任务,即判断相继出现的两个刺激的时距哪个更长（或更短）。时间任务中的一个刺激与记忆内容完全相同,相应的另一个刺激与记忆内容在形状和颜色上都不同。重复条件下,被试忽略第一个刺激,仅完成时间判断任务。结果发现,时间间隔（ISI）短时,记忆匹配条件下的准确率更高,匹配刺激延长了知觉的时间;但随着时间间隔的增加,工作记忆匹配对时间判断的影响降低甚至消失。并且,长或短ISI,记忆任务或重复条件下,目标时距长时,记忆匹配反而缩短了知觉的时间。研究说明工作记忆对时间判断的影响是灵活的,受到注意或工作记忆等高级认知系统的调控。     

基于客体的注意对客体工作记忆的复述作用

客体工作记忆对选择性注意具有自动导向作用.本研究采用自然图片为材料考察了基于客体的选择性注意对客体工作记忆积极保持信息表征的复述作用.根据实验中阻止基于注意的复述的方式不同,本研究共进行了两个实验:实验一通过不呈现记忆匹配项来阻止基于注意的复述,实验二通过突显将注意转移至非记忆匹配项来阻止基于注意的复述.实验结果表明,基于客体的选择性注意对客体工作记忆积极保持物体表征起着重要的复述作用.     

The impact of object working memory on timing

Nontemporal information processing involving short-term memory requirements disturbs time estimation. Previous studies mostly used letters or digits, which are maintained in working memory by phonological loops. Since verbal and nonverbal information are processed by separate working-memory subsystems, how do nonverbal, object-based memory tasks affect time estimation? We manipulated visual object memory load using the magic cube materials. Participants were divided into three groups, who completed a reaction-time task (control task), a memory-recognition task interposed by an attempt to produce a 2500-ms time interval (active processing), and a memory-recognition task following time interval production (passive retention). The produced time increased with increasing memory-object size under both the active processing and passive retention conditions; mean produced time interval did not significantly differ between the two experimental conditions. By comparing the reaction times and error rates of a relevant task, we excluded any speed–accuracy tradeoff during timing. This result suggests that when the working-memory information to be processed includes objects requiring attention for retention, the production of time intervals is also affected by memory item maintenance.     

How verbal memory loads consume attention

According to a traditional assumption about working memory, participants retain a series of verbal items for immediate recall using covert verbal rehearsal, without much need for attention. We reassessed this assumption by imposing a speeded, nonverbal choice reaction time (CRT) task following the presentation of each digit in a list to be recalled. When the memory load surpassed a few items, performance on the speeded CRT task became increasingly impaired. This CRT task impairment depended only on attention-related components of working memory; it was not alleviated by the presence of an auditory memory trace that automatically helped the recall of items at the ends of spoken lists. We suggest that attention-demanding refreshing of verbal stimuli occurs along with any covert rehearsal.     

On the nature of the span of apprehension

Summary Typically, people can only report about four or five items from a briefly presented array of alphanumeric items. A new span task was used to explore the basis of this limitation. In Experiment l, performance suffered when very brief display durations were combined with a verbal-load task, but no significant effects of display duration were found when there was no verbal load. In Experiment 2, a similar interaction was observed between verbal load and the presence of a visual suffix; performance was worse in the verbal-load condition with a visual suffix, but no such effect was observed without verbal load. In both experiments, poorer performance was associated with enhanced serial-position effects. The results can be explained on the assumption that the verbal-load task required some processing resources, and that the quality of information in visual working memory depends on available resources. Thus, both brief-array presentation and the visual suffix degrade the information in visual working memory, but span performance is impaired only when processing resources are relatively scarce.     

Hemispatial neglect and serial order in verbal working memory

Working memory refers to our ability to actively maintain and process a limited amount of information during a brief period of time. Often, not only the information itself but also its serial order is crucial for good task performance. It was recently proposed that serial order is grounded in spatial cognition. Here, we compared performance of a group of right hemisphere-damaged patients with hemispatial neglect to healthy controls in verbal working memory tasks. Participants memorized sequences of consonants at span level and had to judge whether a target consonant belonged to the memorized sequence (item task) or whether a pair of consonants were presented in the same order as in the memorized sequence (order task). In line with this idea that serial order is grounded in spatial cognition, we found that neglect patients made significantly more errors in the order task than in the item task compared to healthy controls. Furthermore, this deficit seemed functionally related to neglect severity and was more frequently observed following right posterior brain damage. Interestingly, this specific impairment for serial order in verbal working memory was not lateralized. We advance the hypotheses of a potential contribution to the deficit of serial order in neglect patients of either or both (1) reduced spatial working memory capacity that enables to keep track of the spatial codes that provide memorized items with a positional context, (2) a spatial compression of these codes in the intact representational space.     

Is the interference between memory processing and timing specific to the use of verbal material?

Increasing load in a memory task performed simultaneously with a timing task shortens perceived time, an effect that has been observed previously with memory tasks using verbal material. The present experiments examine whether two similar memory tasks, one in which verbal material is used and another one in which nonverbal material is used, would produce similar interference effects on concurrent time reproduction. In Experiment 1, the number of nonverbal stimuli (pseudo‐random dot patterns) was manipulated in a memory task performed while a temporal interval to be reproduced was encoded. Reproductions shortened proportionally to the duration of memory processing executed during time estimation. Verbal stimuli (consonants) were used in Experiment 2 in otherwise identical experimental conditions. Effects observed in Experiment 2 were comparable to those obtained in Experiment 1. Taken together, these results support the notion that interference from memory tasks on concurrent time estimation is not determined by the specific type of material processed in memory, but instead by the duration of memory processing.     

Is the interference between memory processing and timing specific to the use of verbal material?

Increasing load in a memory task performed simultaneously with a timing task shortens perceived time, an effect that has been observed previously with memory tasks using verbal material. The present experiments examine whether two similar memory tasks, one in which verbal material is used and another one in which nonverbal material is used, would produce similar interference effects on concurrent time reproduction. In Experiment 1, the number of nonverbal stimuli (pseudo-random dot patterns) was manipulated in a memory task performed while a temporal interval to be reproduced was encoded. Reproductions shortened proportionally to the duration of memory processing executed during time estimation. Verbal stimuli (consonants) were used in Experiment 2 in otherwise identical experimental conditions. Effects observed in Experiment 2 were comparable to those obtained in Experiment 1. Taken together, these results support the notion that interference from memory tasks on concurrent time estimation is not determined by the specific type of material processed in memory, but instead by the duration of memory processing.     

What you say matters: exploring visual-verbal interactions in visual working memory

The aim of this study was to explore whether the content of a simple concurrent verbal load task determines the extent of its interference on memory for coloured shapes. The task consisted of remembering four visual items while repeating aloud a pair of words that varied in terms of imageability and relatedness to the task set. At test, a cue appeared that was either the colour or the shape of one of the previously seen objects, with participants required to select the object's other feature from a visual array. During encoding and retention, there were four verbal load conditions: (a) a related, shape-colour pair (from outside the experimental set, i.e., "pink square"); (b) a pair of unrelated but visually imageable, concrete, words (i.e., "big elephant"); (c) a pair of unrelated and abstract words (i.e., "critical event"); and (d) no verbal load. Results showed differential effects of these verbal load conditions. In particular, imageable words (concrete and related conditions) interfered to a greater degree than abstract words. Possible implications for how visual working memory interacts with verbal memory and long-term memory are discussed.     

What you say matters: Exploring visual–verbal interactions in visual working memory

The aim of this study was to explore whether the content of a simple concurrent verbal load task determines the extent of its interference on memory for coloured shapes. The task consisted of remembering four visual items while repeating aloud a pair of words that varied in terms of imageability and relatedness to the task set. At test, a cue appeared that was either the colour or the shape of one of the previously seen objects, with participants required to select the object's other feature from a visual array. During encoding and retention, there were four verbal load conditions: (a) a related, shape–colour pair (from outside the experimental set, i.e., “pink square”); (b) a pair of unrelated but visually imageable, concrete, words (i.e., “big elephant”); (c) a pair of unrelated and abstract words (i.e., “critical event”); and (d) no verbal load. Results showed differential effects of these verbal load conditions. In particular, imageable words (concrete and related conditions) interfered to a greater degree than abstract words. Possible implications for how visual working memory interacts with verbal memory and long-term memory are discussed.