Temporal dynamics of different levels of feature representation in working memory binding: An EEG and iEEG study

AbstractAlterations of resting-state EEG microstates have been associated with various neurological disorders and behavioral states. Interestingly, age-related differences in EEG microstate organization have also been reported, and it has been suggested that resting-state EEG activity may predict cognitive capacities in healthy individuals across the lifespan. In this exploratory study, we performed a microstate analysis of resting-state brain activity and tested allocentric spatial working memory performance in healthy adult individuals: twenty 25–30-year-olds and twenty-five 64–75-year-olds. We found a lower spatial working memory performance in older adults, as well as age-related differences in the five EEG microstate maps A, B, C, C′ and D, but especially in microstate maps C and C′. These two maps have been linked to neuronal activity in the frontal and parietal brain regions which are associated with working memory and attention, cognitive functions that have been shown to be sensitive to aging. Older adults exhibited lower global explained variance and occurrence of maps C and C′. Moreover, although there was a higher probability to transition from any map towards maps C, C′ and D in young and older adults, this probability was lower in older adults. Finally, although age-related differences in resting-state EEG microstates paralleled differences in allocentric spatial working memory performance, we found no evidence that any individual or combination of resting-state EEG microstate parameter(s) could reliably predict individual spatial working memory performance. Whether the temporal dynamics of EEG microstates may be used to assess healthy cognitive aging from resting-state brain activity requires further investigation.

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Temporal Dynamics of Attention during Encoding versus Maintenance of Working Memory: Complementary Views from Event-related Potentials and Alpha-band Oscillations

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_00727 ◽

2015 ◽

Vol 27 (3) ◽

pp. 492-508 ◽

Cited By ~ 62

Author(s):

Nicholas E. Myers ◽

Lena Walther ◽

George Wallis ◽

Mark G. Stokes ◽

Anna C. Nobre

Keyword(s):

Working Memory ◽

Visual Information ◽

Temporal Dynamics ◽

Recall Performance ◽

Event Related Potentials ◽

Alpha Band ◽

Related Potentials ◽

Frontoparietal Control Network ◽

Anticipatory Attention ◽

Processing Differences

Working memory (WM) is strongly influenced by attention. In visual WM tasks, recall performance can be improved by an attention-guiding cue presented before encoding (precue) or during maintenance (retrocue). Although precues and retrocues recruit a similar frontoparietal control network, the two are likely to exhibit some processing differences, because precues invite anticipation of upcoming information whereas retrocues may guide prioritization, protection, and selection of information already in mind. Here we explored the behavioral and electrophysiological differences between precueing and retrocueing in a new visual WM task designed to permit a direct comparison between cueing conditions. We found marked differences in ERP profiles between the precue and retrocue conditions. In line with precues primarily generating an anticipatory shift of attention toward the location of an upcoming item, we found a robust lateralization in late cue-evoked potentials associated with target anticipation. Retrocues elicited a different pattern of ERPs that was compatible with an early selection mechanism, but not with stimulus anticipation. In contrast to the distinct ERP patterns, alpha-band (8–14 Hz) lateralization was indistinguishable between cue types (reflecting, in both conditions, the location of the cued item). We speculate that, whereas alpha-band lateralization after a precue is likely to enable anticipatory attention, lateralization after a retrocue may instead enable the controlled spatiotopic access to recently encoded visual information.

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Integrating Theories of Working Memory

Working Memory ◽

10.1093/oso/9780198842286.003.0014 ◽

2020 ◽

pp. 389-430

Author(s):

Robert H. Logie ◽

Clément Belletier ◽

Jason M. Doherty

Keyword(s):

Working Memory ◽

Empirical Evidence ◽

Cognitive Functions ◽

Scientific Progress ◽

Theoretical Framework ◽

Theoretical Frameworks ◽

Levels Of Explanation ◽

Research Questions ◽

Multiple Component ◽

Different Levels

Multiple theories of working memory are described in the chapters of this book and often these theories are viewed as being mutually incompatible, yet each is associated with a supporting body of empirical evidence. This chapter argues that many of these differences reflect different research questions, different levels of explanation, and differences in how participants perform their assigned tasks in different laboratories, rather than fundamental theoretical adversity. It describes a version of a multiple component working memory in which a range of specialized cognitive functions (or mental tools) act in concert, giving the impression, at a different level of explanation, of a unified cognitive system. The chapter argues that more rapid and more substantial scientific progress on the understanding of the concept of working memory would be achieved through identifying the levels of explanation explored within each theoretical framework, and attempting to integrate theoretical frameworks rather than perpetuating debate with no clear resolution in sight.

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Saliency-based Rhythmic Coordination of Perceptual Predictions

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_01371 ◽

2020 ◽

Vol 32 (2) ◽

pp. 201-211 ◽

Cited By ~ 1

Author(s):

Qiaoli Huang ◽

Huan Luo

Keyword(s):

Temporal Dynamics ◽

Theta Band ◽

Behavioral Profile ◽

Fine Grained ◽

Attentional Process ◽

Behavioral Measurement ◽

Processing Resources ◽

Rhythmic Coordination ◽

The Brain ◽

Different Levels

Objects, shown explicitly or held in mind internally, compete for limited processing resources. Recent studies have demonstrated that attention samples locations and objects rhythmically. Interestingly, periodic sampling not only operates over objects in the same scene but also occurs for multiple perceptual predictions that are held in attention for incoming inputs. However, how the brain coordinates perceptual predictions that are endowed with different levels of bottom–up saliency information remains unclear. To address the issue, we used a fine-grained behavioral measurement to investigate the temporal dynamics of processing of high- and low-salient visual stimuli, which have equal possibility to occur within experimental blocks. We demonstrate that perceptual predictions associated with different levels of saliency are organized via a theta-band rhythmic course and are optimally processed in different phases within each theta-band cycle. Meanwhile, when the high- and low-salient stimuli are presented in separate blocks and thus not competing with each other, the periodic behavioral profile is no longer present. In summary, our findings suggest that attention samples and coordinates multiple perceptual predictions through a theta-band rhythm according to their relative saliency. Our results, in combination with previous studies, advocate the rhythmic nature of attentional process.

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Stable population coding for working memory coexists with heterogeneous neural dynamics in prefrontal cortex

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1619449114 ◽

2016 ◽

Vol 114 (2) ◽

pp. 394-399 ◽

Cited By ~ 128

Author(s):

John D. Murray ◽

Alberto Bernacchia ◽

Nicholas A. Roy ◽

Christos Constantinidis ◽

Ranulfo Romo ◽

...

Keyword(s):

Working Memory ◽

Prefrontal Cortex ◽

Neural Circuit ◽

Temporal Dynamics ◽

Population Level ◽

Population Coding ◽

Neural Dynamics ◽

Stable Population ◽

Neuron Activity ◽

Delayed Response

Working memory (WM) is a cognitive function for temporary maintenance and manipulation of information, which requires conversion of stimulus-driven signals into internal representations that are maintained across seconds-long mnemonic delays. Within primate prefrontal cortex (PFC), a critical node of the brain’s WM network, neurons show stimulus-selective persistent activity during WM, but many of them exhibit strong temporal dynamics and heterogeneity, raising the questions of whether, and how, neuronal populations in PFC maintain stable mnemonic representations of stimuli during WM. Here we show that despite complex and heterogeneous temporal dynamics in single-neuron activity, PFC activity is endowed with a population-level coding of the mnemonic stimulus that is stable and robust throughout WM maintenance. We applied population-level analyses to hundreds of recorded single neurons from lateral PFC of monkeys performing two seminal tasks that demand parametric WM: oculomotor delayed response and vibrotactile delayed discrimination. We found that the high-dimensional state space of PFC population activity contains a low-dimensional subspace in which stimulus representations are stable across time during the cue and delay epochs, enabling robust and generalizable decoding compared with time-optimized subspaces. To explore potential mechanisms, we applied these same population-level analyses to theoretical neural circuit models of WM activity. Three previously proposed models failed to capture the key population-level features observed empirically. We propose network connectivity properties, implemented in a linear network model, which can underlie these features. This work uncovers stable population-level WM representations in PFC, despite strong temporal neural dynamics, thereby providing insights into neural circuit mechanisms supporting WM.

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Early Top–Down Control of Visual Processing Predicts Working Memory Performance

Journal of Cognitive Neuroscience ◽

10.1162/jocn.2009.21257 ◽

2010 ◽

Vol 22 (6) ◽

pp. 1224-1234 ◽

Cited By ~ 83

Author(s):

Aaron M. Rutman ◽

Wesley C. Clapp ◽

James Z. Chadick ◽

Adam Gazzaley

Keyword(s):

Working Memory ◽

Selective Attention ◽

Visual Processing ◽

Temporal Dynamics ◽

Memory Performance ◽

Event Related Potential ◽

Natural Scenes ◽

Attention And Memory ◽

Top Down ◽

Sensory Neural

Selective attention confers a behavioral benefit on both perceptual and working memory (WM) performance, often attributed to top–down modulation of sensory neural processing. However, the direct relationship between early activity modulation in sensory cortices during selective encoding and subsequent WM performance has not been established. To explore the influence of selective attention on WM recognition, we used electroencephalography to study the temporal dynamics of top–down modulation in a selective, delayed-recognition paradigm. Participants were presented with overlapped, “double-exposed” images of faces and natural scenes, and were instructed to either remember the face or the scene while simultaneously ignoring the other stimulus. Here, we present evidence that the degree to which participants modulate the early P100 (97–129 msec) event-related potential during selective stimulus encoding significantly correlates with their subsequent WM recognition. These results contribute to our evolving understanding of the mechanistic overlap between attention and memory.

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Effects of Working Memory Capacity, Task Switching, and Task Difficulty on Multitasking Performance

Proceedings of the Human Factors and Ergonomics Society Annual Meeting ◽

10.1177/1541931213601114 ◽

2016 ◽

Vol 60 (1) ◽

pp. 502-506 ◽

Cited By ~ 2

Author(s):

Shijing Liu ◽

Amy Wadeson ◽

Na Young Kim ◽

Chang S. Nam

Keyword(s):

Working Memory ◽

Task Switching ◽

Task Difficulty ◽

Working Memory Capacity ◽

Memory Capacity ◽

Trail Making ◽

Human Operators ◽

Switching Task ◽

Different Levels ◽

And Task

Multitasking requires human operators to handle the demands of multiple tasks through task switching at the same time and this ability is required in many jobs. Previous studies showed that different levels of working memory capacity (WMC) and task switching abilities can lead to differences on multitasking performance. With increased complexity of tasks, maintaining task performance is challenging. This study sought to find the relations of WMC, task switching, task difficulty, and multitasking performance. Multi-Attribute Task Battery II (MATB-II) was employed in this study as a platform to assess multitasking. Automated OSPAN and Trail Making Tasks (TMT) were used to assess WMC and the task switching ability, respectively. Results indicated that there were significant effects of these three parameters on multitasking performance. Other dimensions of multitasking performance will be addressed in future studies.

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