Thinking inside the box: Mental manipulation of working memory contents in 3- to 7-year-old children

AbstractHow does the human brain manage multiple bits of information to guide goal-directed behaviour? Successful working memory (WM) functioning has consistently been linked to oscillatory power in the theta frequency band (4-8 Hz) over fronto-medial cortex (fronto-medial theta, FMT). Specifically, FMT is thought to reflect the mechanism of an executive sub-system that coordinates maintenance of memory contents in posterior regions. However, direct evidence for the role of FMT in controlling specific WM content is lacking. Here we collected high-density Electroencephalography (EEG) data whilst participants engaged in load-varying WM tasks and then used multivariate decoding methods to examine WM content during the maintenance period. Higher WM load elicited a focal increase in FMT. Importantly, decoding of WM content was driven by posterior/parietal sites, which in turn showed load-induced functional theta coupling with fronto-medial cortex. Finally, we observed a significant slowing of FMT frequency with increasing WM load, consistent with the hypothesised broadening of a theta ‘duty cycle’ to accommodate additional WM items. Together these findings demonstrate that frontal theta orchestrates posterior maintenance of WM content. Moreover, the observed frequency slowing elucidates the function of FMT oscillations by specifically supporting phase-coding accounts of WM.Significance StatementHow does the brain juggle the maintenance of multiple items in working memory (WM)? Here we show that increased WM demands increase theta power (4-8 Hz) in fronto-medial cortex. Interestingly, using a machine learning approach, we found that the content held in WM could be read out not from frontal, but from posterior areas. These areas were in turn functionally coupled with fronto-medial cortex, consistent with the idea that frontal cortex orchestrates WM representations in posterior regions. Finally, we observed that holding an additional item in WM leads to significant slowing of the frontal theta rhythm, supporting computational models that postulate longer ‘duty cycles’ to accommodate additional WM demands.

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Working Memory-Driven Attention in Real-World Search

Perception ◽

10.1177/0301006618791688 ◽

2018 ◽

Vol 47 (9) ◽

pp. 966-975 ◽

Cited By ~ 3

Author(s):

Shinyoung Jung ◽

Yosun Yoon ◽

Suk Won Han

Keyword(s):

Working Memory ◽

Attentional Capture ◽

Real World ◽

Target Object ◽

Visual Object ◽

Indoor Scenes ◽

Bias Attention ◽

Memory Contents ◽

Online Catalogue ◽

World Environment

People’s attention is well attracted to stimuli matching their working memory. This memory-driven attentional capture has been demonstrated in simplified and controlled laboratory settings. The present study investigated whether working memory contents capture attention in a setting that closely resembles real-world environment. In the experiment, participants performed a task of searching for a target object in real-world indoor scenes, while maintaining a visual object in working memory. To create a setting similar to real-world environment, images taken from IKEA®’s online catalogue were used. The results showed that participants’ attention was biased toward a working memory-matching object, interfering with the target search. This was so even when participants did not expect that a memory-matching stimulus would appear in the search array. These results suggest that working memory can bias attention in complex, natural environment and this memory-driven attentional capture in real-world setting takes place in an automatic manner.

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School-aged children's awareness of their own working memory contents

10.32469/10355/67672 ◽

2018 ◽

Author(s):

◽

Christopher L. Blume

Keyword(s):

Working Memory ◽

Cognitive Task ◽

Age Groups ◽

Visual Array ◽

Memory Contents ◽

The Many ◽

The Individual ◽

The Mind ◽

Subjective Estimates ◽

Do So

Working memory researchers in psychology have long wondered about how the mind organizes the many different pieces of information that must be maintained at any one time in order that the individual may carry out daily tasks of cognition. This research has often focused on the capacity of information that an individual is capable of holding in mind at any one time. In order to obtain a better understanding of this capacity researchers have developed what are thought to be objective measures of estimating the number of items (k) an individual must have in mind based on their performance on some cognitive task. In the present research one such formula is used to obtain a typical estimate for a visual array task in which multiple colored squares must be held in mind for a short duration before the participant is asked about whether or not a single probe color was one of the colors that had just seen in the array. In addition, participants are asked to provide their own subjective estimates of the number of colors they believe themselves to have memorized. Several age groups were tested starting with children as young as 6. The results show that while all age groups appear to overestimate their own capacity when compared to the objective k estimate, younger children tend to do so to a greater degree. This effect is discussed as the result of the development of quicker processing with age, faster forgetting in young age, or simply a structural increase in the capacity irrespective of the prior two possibilities.

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Memory as Tinted Lens: Working Memory Contents Distort Perception

Journal of Vision ◽

10.1167/jov.20.11.1494 ◽

2020 ◽

Vol 20 (11) ◽

pp. 1494

Author(s):

Hyung-Bum Park ◽

Weiwei Zhang

Keyword(s):

Working Memory ◽

Memory Contents

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Chimpanzees flexibly update working memory contents and show susceptibility to distraction in the self-ordered search task

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2019.0715 ◽

2019 ◽

Vol 286 (1907) ◽

pp. 20190715 ◽

Cited By ~ 4

Author(s):

Christoph J. Völter ◽

Roger Mundry ◽

Josep Call ◽

Amanda M. Seed

Keyword(s):

Working Memory ◽

Individual Differences ◽

Homo Sapiens ◽

Large Individual ◽

Long Term Memory ◽

Spatial Cues ◽

Key Factor ◽

Attentional Interference ◽

Memory Contents ◽

Object Features

Working memory (WM) is a core executive function that allows individuals to hold, process and manipulate information. WM capacity has been repeatedly nominated as a key factor in human cognitive evolution; nevertheless, little is known about the WM abilities of our closest primate relatives. In this study, we examined signatures of WM ability in chimpanzees ( Pan troglodytes ). Standard WM tasks for humans ( Homo sapiens ) often require participants to continuously update their WM. In Experiment 1, we implemented this updating requirement in a foraging situation: zoo-housed chimpanzees ( n = 13) searched for food in an array of containers. To avoid redundant searches, they needed to continuously update which containers they had already visited (similar to WM paradigms for human children) with 15 s retention intervals in between each choice. We examined chimpanzees' WM capacity and to what extent they used spatial cues and object features to memorize their previous choices. In Experiment 2, we investigated how susceptible their WM was to attentional interference, an important signature, setting WM in humans apart from long-term memory. We found large individual differences with some individuals remembering at least their last four choices. Chimpanzees used a combination of spatial cues and object features to remember which boxes they had chosen already. Moreover, their performance decreased specifically when competing memory information was introduced. Finally, we found that individual differences in task performance were highly reliable over time. Together, these findings show remarkable similarities between human and chimpanzee WM abilities despite evolutionary and life-history differences.

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Selective Attention to Elements in Working Memory

Experimental Psychology (formerly Zeitschrift für Experimentelle Psychologie) ◽

10.1026//1618-3169.50.4.257 ◽

2003 ◽

Vol 50 (4) ◽

pp. 257-269 ◽

Cited By ~ 75

Author(s):

Klaus Oberauer

Keyword(s):

Working Memory ◽

Switch Cost ◽

Arithmetic Operation ◽

Memory Task ◽

Focus Of Attention ◽

Set Size ◽

Switch Costs ◽

Memory Contents ◽

With Memory ◽

Selective Access

Abstract. Three experiments with an arithmetic working memory task examine the object switch effect first reported by Garavan (1998 ; Garavan (1998 ), which was interpreted as evidence for a focus of attention within working memory. Experiments 1a and 1b showed object switch costs with a task that requires selective access to items in working memory, but did not involve counting, and did not require updating of working memory contents, thus ruling out two alternative explanations of Garavan’s results. Experiment 2 showed object switch costs with a task that required no selective access to working memory contents, but involved updating, thus providing evidence for a second component to the overall object switch costs. Further analyses revealed that the object switch cost increased with memory set size; that there were (smaller) switch costs when the switch was to an item of the same type; that repeating an arithmetic operation does not have the same effect as repeating the object it is applied to; and that object switching is not mediated by backward inhibition of the previously focused object.

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