Storage and processing in visuo-spatial working memory

Visuo-spatial working memory has been used to account for performance in a wide range of visuo-spatial tasks, including perceptuo-motor tracking and immediate recall of visually presented patterns. However a developing body of evidence points to a fractionation of the concept into visuo-spatial processing that calls on general purpose executive resources, and a visual 'cache' memory for temporary storage in on-line cognition. Two related experiments are described which address whether processing and temporary memory draw on overlapping or on distinct resources in working memory. Experiment 1 demonstrates that participants can accurately respond to a series of targets appearing in random locations whether or not they have the additional load of retaining and subsequently recalling the appearance of each target. Memory for target appearance likewise is largely unaffected by the additional load of requiring a response to each target. Experiment 2 demonstrates similar findings when verbal labeling of the patterns is inhibited through the use of articulatory suppression. Results are interpreted as consistent with a multiple component working memory system.     

The effects of autobiographical memory and visual perspective on working memory

The present research aims to explore whether recalling and writing about autobiographical memory from different perspectives (first-person perspective vs. third-person perspective) could affect cognitive function. The participants first performed a working memory task to evaluate their working memory capacity as a baseline and then were instructed to recall (Study 1) or write about (Study 2) personal events (failures vs. successes) from the first-person perspective or the third-person perspective. Finally, they performed the working memory task again. The results suggested that autobiographical memory and perspective influence working memory interactively. When recalling a success, the participants who recalled from the third-person perspective performed better than those who recalled from the first-person perspective on the working memory capacity task; when recalling a failure, the opposite was true.     

Effect of negative emotional content on attentional maintenance in working memory

ABSTRACT

Previous research has shown that emotional stimuli may interfere with working memory (WM) processes, but little is known about the process affected. Using a complex span task, the present study investigated the influence of processing negative emotional content on attentional maintenance in WM. In two experiments conducted under articulatory suppression, participants were asked to remember a series of five letters, each of which was followed by an image to be categorised. In half of the trials, the images were negative and in the other half, they were neutral. In both experiments, our results showed longer processing times for emotional stimuli than neutral stimuli, and lower memory performance when participants processed negative stimuli. We propose that emotional stimuli direct more attentional resources towards the processing component of the WM task, thereby reducing the storage capacity available for the items that are to be remembered.     

The personalisation method applied to a working memory task: Evidence of long-term working memory effects

Ericsson and Kintsch (1995) proposed that, in situations of expertise, individuals can overcome working memory limitations by using long-term working memory. It allows a greater capacity than working memory thanks to long-term memory encoding and retrieving. To test this characteristic, an adaptation of Daneman and Carpenter's (1980) reading span was used. To operationalise expertise, the personalisation method (Guida & Tardieu, 2005) was employed. In Experiment 1, a personalised group, which read reading span sentences that mentioned familiar locations, was compared to a nonpersonalised group, which read sentences with unfamiliar locations. In Experiment 2, a personalised group, which read reading span sentences with neutral locations, was encouraged to mentally personalise these locations by thinking about known locations. This group was compared to a nonpersonalised group, which was encouraged to think about unknown locations. The personalised groups were expected to store and retrieve information in long-term memory via long-term working memory more easily than the nonpersonalised groups, which had to count massively on working memory. The results showed that personalisation enhanced reading span and confirmed one implication of the long-term working memory theory: high- and low-reading-span differences could also be due to long-term memory retrieval. Finally, these results are interpreted in terms of interaction between working memory size and long-term memory knowledge, showing that participants with a lower reading span benefited more from high domain knowledge than participants with a higher reading span.     

Examining the effects of frustration on working memory capacity

The present study attempts to expand our understanding of frustration, clinical symptoms, and working memory by examining the unique contribution of attention-deficit/hyperactivity disorder symptoms and frustration to working memory capacity (WMC). A factor-analytic framework was utilized to isolate and examine WMC based on results from three working memory tasks that were administered in counterbalanced order to control for individual differences in baseline WMC. All participants provided subjective ratings of frustration both prior to and after administration of a frustration induction. Results suggest that although we were able to systematically induce subjective frustration for participants in the experimental group relative to the control group, WMC was not associated with induced frustration in the present study. Results also indicated that inattention symptoms predicted baseline frustration levels. This work highlights the need to examine the extent to which storage/rehearsal WMC and additional process-oriented working memory-related performance variables are related to frustration. The data that support the findings of this study are available from the corresponding author upon request.     

Development of dopaminergic genetic associations with visuospatial,verbal and social working memory

Dopamine transmission in the prefrontal cortex (PFC) supports working memory (WM), the temporary holding, processing and manipulation of information in one's mind. The gene coding the catechol‐O‐methyltransferase (COMT) enzyme, which degrades dopamine, in particular in the PFC, has a common single nucleotide polymorphism leading to two versions of the COMT enzyme which vary in their enzymatic activity. The methionine (Met) allele has been associated with higher WM performance and lower activation of the PFC in executive function tasks than the valine (Val) allele. In a previous study, COMT genotype was associated with performance on verbal and visuospatial WM tasks in adults, as well as with performance on a novel social WM paradigm that requires participants to maintain and manipulate information about the traits of their friends or family over a delay. Here, data collected in children and adolescents (N = 202) were compared to data from the adult sample (N = 131) to investigate possible age differences in genetic associations. Our results replicate and extend previous work showing that the pattern of superior WM performance observed in Met/Met adults emerges during development. These findings are consistent with a decrease in prefrontal dopamine levels during adolescence. Developmentally moderated genetic effects were observed for both visuospatial and social WM, even when controlling for non‐social WM performance, suggesting that the maintenance and manipulation of social information may also recruit the dopamine neurotransmitter system. These findings show that development should be considered when trying to understand the impact of genetic polymorphisms on cognitive function.     

Applying a dual process model of self-regulation: The association between executive working memory capacity,negative urgency,and negative mood induction on pre-potent response inhibition

This study tested a dual-process model of self-control where the combination of high impulsivity (negative urgency – NU), weak reflective/control processes (low executive working memory capacity – E-WMC), and a cognitive load is associated with increased failures to inhibit pre-potent responses on a cued go/no-go task. Using a within-subjects design, a cognitive load with and without negative emotional load was implemented to consider situational factors. Results suggested that: (1) high NU was associated with low E-WMC; (2) low E-WMC significantly predicted more inhibitory control failures across tasks; and (3) there was a significant interaction of E-WMC and NU, revealing those with low E-WMC and high NU had the highest rates of inhibitory control failures on all conditions of the task. In conclusion, results suggest that while E-WMC is a strong independent predictor of inhibitory control, NU provides additional information for vulnerability to problems associated with self-regulation.     

Trial distinctiveness in visuospatial working memory: effects on individual differences

ABSTRACT

Previous research has shown that proactive interference (PI) negatively affects performance on working memory (WM) tasks, particularly when to-be-remembered items are similar across trials, and that individuals with low WM spans are more susceptible to PI than those with high spans. The two experiments of the present study further explored individual differences in susceptibility to PI in the visuospatial domain. The similarity of the to-be-remembered locations was manipulated across trials by varying whether locations were presented in different colours and/or accompanied by unique sounds. It was hypothesised that these manipulations would reduce PI, improving participants’ memory. In addition, because of their increased susceptibility to PI, it also was hypothesised that low spans would benefit more than high spans from increases in distinctiveness. The results of both experiments were consistent with these hypotheses, suggesting that even low-span individuals can overcome the effects of PI, given the right task support.     

振动触觉频率信息的工作记忆容量及存储机制

工作记忆可以同时保存多个信息并且容量有限, 这一内在机制是工作记忆研究的重点问题。视觉和言语等研究领域都发现工作记忆能够存储多个信息单元, 但对振动触觉工作记忆是否能存储多个频率信息目前尚无相关研究。由于振动触觉频率刺激和视觉刺激具有不同的神经编码机制, 以及振动频率信息是通过躯体感觉产生的模拟的、单维的、参数化信息, 振动触觉工作记忆容量及其加工存储机制的研究也必不可少。首先, 本项目将采用新的实验范式, 探究不同的刺激呈现方式以及不同反应报告方式下, 振动触觉工作记忆的容量及其认知机制。其次, 本项目也将同时运用功能磁共振成像(fMRI)技术, 来阐述振动触觉工作记忆加工存储的神经机制。探究基于触觉频率信息的参数工作记忆容量及其神经机制是完善工作记忆模型的重要补充, 将有助于提高我们对工作记忆系统的理解, 并为视觉、听觉、触觉多模态感知觉信息的跨通道研究奠定基础。     

Time and interference: Effects on working memory

This study tested predictions from the time‐based resource‐sharing (TBRS) model with a classical verbal working memory (WM) task, where target and non‐target information interfere strongly with each other. Different predictions can be formulated according to the dominant perspectives (TBRS and interference hypothesis) on the role of inhibitory control in WM task performance. Here, we aimed to trace the activation of irrelevant information, examining priming effects in a lexical decision task immediately following WM recall. Results indicate the roles of both time and interference constraints in determining task performance. In particular, the role of time available seemed crucial at the highest WM loads (i.e., 3 and 4 memoranda). These were also associated with a higher activation of no‐longer‐relevant information but, in this case, independently from time available for processing.     

The effects of active worrying on working memory capacity

According to the attentional control theory, worry, a crucial component of anxiety, impairs task performance through its direct effect on working memory capacity (WMC) by using up the limited resources available for performance thus reducing attentional control. We tested this hypothesis in the current study by examining the causal influence of active worrying on WMC in a sample of undergraduate university students (n?=?64) assigned either to a worry condition or to a non-worry control condition. Participants performed a change detection task before and after the worry/control manipulation. Mediation analyses showed that the level of self-reported worry mediated the effects of condition on change in WMC as demonstrated by the significant indirect effect of worry and the resulting non-significant direct effect of condition on change in WMC. Similar results were obtained when using state anxiety measures as mediating factors. Results of the current study are amongst the first to demonstrate that worry impairs WMC and as such have important implications for understanding the impact of worry.     

工作记忆中的积极效应：情绪效价与任务相关性的影响

积极效应指相比于年轻人, 老年人更倾向于优先加工积极情绪刺激而非消极情绪刺激。近年来工作记忆的研究发现积极效应会受到情绪效价与任务相关性的影响：情绪效价作为任务相关属性的研究支持工作记忆中存在积极效应, 具体表现为老年人对积极情绪刺激记忆的增强, 以及对消极情绪刺激记忆的减弱; 情绪效价作为工作记忆任务无关属性的研究相对较少, 且未发现一致的积极效应, 提示情绪效价及任务相关性均为影响工作记忆积极效应的关键因素。脑成像的研究初步表明, 工作记忆中情绪加工上的年龄效应与背侧执行系统和腹侧情绪系统的随龄功能变化有关。社会情绪选择理论与双竞争模型对工作记忆中的积极效应具备较大的解释力, 而动态整合理论尚缺乏实证研究支持。未来研究可进一步探究老年人工作记忆不同阶段情绪加工的特点, 澄清不同情绪材料内在编码过程上的差异对积极效应发生机制的潜在影响, 探讨情绪效价及任务相关性影响工作记忆积极效应的关键神经环路, 并揭示情绪工作记忆训练提升老年人认知功能与情绪体验的内在机制及其潜在应用价值。     

Strategic and automatic effects of visual working memory on attention in visual search

Previous research indicates that visual attention can be automatically captured by sensory inputs that match the contents of visual working memory. However, Woodman and Luck (2007) showed that information in working memory can be used flexibly as a template for either selection or rejection according to task demands. We report two experiments that extend their work. Participants performed a visual search task while maintaining items in visual working memory. Memory items were presented for either a short or long exposure duration immediately prior to the search task. Memory was tested by a change-detection task immediately afterwards. On a random half of trials items in memory matched either one distractor in the search task (Experiment 1) or three (Experiment 2). The main result was that matching distractors speeded or slowed target detection depending on whether memory items were presented for a long or short duration. These effects were more in evidence with three matching distractors than one. We conclude that the influence of visual working memory on visual search is indeed flexible but is not solely a function of task demands. Our results suggest that attentional capture by perceptual inputs matching information in visual working memory involves a fast automatic process that can be overridden by a slower top-down process of attentional avoidance.     

Gender differences in episodic memory and visual working memory including the effects of age

Analysing the relationship between gender and memory, and examining the effects of age on the overall memory-related functioning, are the ongoing goals of psychological research. The present study examined gender and age group differences in episodic memory with respect to the type of task. In addition, these subgroup differences were also analysed in visual working memory. A sample of 366 women and 330 men, aged between 16 and 69 years of age, participated in the current study. Results indicate that women outperformed men on auditory memory tasks, whereas male adolescents and older male adults showed higher level performances on visual episodic and visual working memory measures. However, the size of gender-linked effects varied somewhat across age groups. Furthermore, results partly support a declining performance on episodic memory and visual working memory measures with increasing age. Although age-related losses in episodic memory could not be explained by a decreasing verbal and visuospatial ability with age, women's advantage in auditory episodic memory could be explained by their advantage in verbal ability. Men's higher level visual episodic memory performance was found to result from their advantage in visuospatial ability. Finally, possible methodological, biological, and cognitive explanations for the current findings are discussed.     

Rhythmic information in working memory: effects of concurrent articulation on reproduction of rhythms

The study addressed a previously neglected issue in the concept of working memory, namely whether or not rhythmical information is coded and maintained in a phonological loop. Thirty subjects engaged in a task which required them to reproduce the temporal sequence of rhythm. The results showed that the reproduction of rhythm was dramatically reduced by a concurrent articulation, and that the deterioration of rhythm reproduction was larger than that obtained with a concurrent spatial task which would not diminish the activity of the phonological loop directly. An articulatory component of the working memory apparently plays an important role in memorizing rhythms. Furthermore, the sparse-dense rhythm (a pattern which started with sparse temporal structure and ended with a dense one) allowed better memorization than a dense-sparse pattern. The sources of the sparse-dense superiority effect are discussed in terms of the working memory for rhythmic information.     

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.     

长时联结表征对工作记忆的抑制效应

本研究通过两个实验探讨了长时记忆联结表征如何影响当下工作记忆任务的加工。长时记忆联结表征采用无语义联系、无视觉相似性的Emoji图片对,提前一天让被试完成联结表征的建立,正式工作记忆任务采用独立探测的变化觉察范式。实验1控制呈现时间(500 ms/1000 ms)与呈现方式(联结/独立),发现两种呈现时间均显示出联结条件的正确率与记忆容量显著低于独立条件,说明长时记忆联结表征抑制了当前工作记忆的加工。实验2设置了记忆项目数(2/4/6项)与呈现方式(联结/独立),采用alpha震荡作为脑电指标,考察长时联结表征在工作记忆维持阶段的作用。结果发现在维持阶段,独立条件的alpha震荡随着记忆项目数量的增加而增大(2项<4项<6项),而联结条件在4项已经到达顶点(2项<4项=6项)。实验2进一步说明长时联结表征在维持阶段降低了当前工作记忆容量。本研究的两个实验结果表明,长时记忆联结表征对当前的工作记忆任务有一定的抑制作用,这种抑制作用产生的机制可能来自于联结表征干扰了维持阶段的注意分配。     

The effects of aging on the working memory processes of multimodal information

Normal aging is associated with deficits in working memory processes. However, the majority of research has focused on storage or inhibitory processes using unimodal paradigms, without addressing their relationships using different sensory modalities. Hence, we pursued two objectives. First, was to examine the effects of aging on storage and inhibitory processes. Second, was to evaluate aging effects on multisensory integration of visual and auditory stimuli. To this end, young and older participants performed a multimodal task for visual and auditory pairs of stimuli with increasing memory load at encoding and interference during retention. Our results showed an age-related increased vulnerability to interrupting and distracting interference reflecting inhibitory deficits related to the off-line reactivation and on-line suppression of relevant and irrelevant information, respectively. Storage capacity was impaired with increasing task demands in both age groups. Additionally, older adults showed a deficit in multisensory integration, with poorer performance for new visual compared to new auditory information.     

Age and synchrony effects in visuospatial working memory

Younger and older adults were administered a computerized version of the Corsi Block visuospatial working memory (VSWM) span task at either their peak or off-peak time of day and in either a high-interference (ascending order of administration, starting with short lists first) or low-interference (descending order, starting with longest lists first) format. Young adults' span scores were highest in the ascending format. By contrast, older adults performed better in the low-interference format, replicating findings with verbal memory span studies. Although both age groups benefited from being tested at their peak time, the advantage was far greater for older adults, but only in the low-interference format; their scores on the high-interference format were not helped by peak-time testing. These findings are consistent with the suggestion that young adults' performance on span tasks is influenced by practice and strategies, but the performance of older adults is heavily influenced by interference—which is best controlled at peak times of day. Our findings suggest that both time of testing and interference play critical roles in determining age differences in VSWM span, and both a reduction in interference and peak-time testing may be necessary to optimize older adults' performance and to maximize the reduction in age differences.     

空间距离对视觉工作记忆巩固的影响

以往研究发现,个体对不同类型的视觉信息进行视觉工作记忆巩固的模式存在差异,如对于方向信息,一次只能有一个项目被巩固进入视觉工作记忆系统,而对于颜色信息,个体则可以一次巩固两个项目进入视觉工作记忆系统。但对于视觉信息的巩固模式是否会受其他因素的影响,目前仍然没有明确的定论。本研究将探讨视觉信息的巩固模式是否可能受到记忆项目空间距离因素的影响。研究采用变化觉察范式、序列-同时呈现操作及控制记忆项目呈现间距的方法,通过3个实验考察记忆项目之间的空间距离是否能够影响个体对颜色信息和方向信息的巩固模式。在三种空间距离水平上序列呈现或同时呈现两个记忆项目,实验结果一致发现记忆项目之间的空间距离会对视觉工作记忆巩固模式产生明显影响,个体在同时呈现条件下的正确率会随着空间距离的增大而降低。这些结果表明对同一类视觉信息进行巩固的过程中所存在的项目数量限制并不是固定的,个体可以采用序列模式或有限容量的并行模式对同一类信息进行巩固,巩固的模式可能与视觉空间注意的分配以及视觉信息所能获得的注意资源有关。