A dual mechanism underlying retroactive shifts of auditory spatial attention: dissociating target- and distractor-related modulations of alpha lateralization

AbstractAttention can be allocated to mental representations to select information from working memory. To date, it remains ambiguous whether such retroactive shifts of attention involve the inhibition of irrelevant information or the prioritization of relevant information. Investigating asymmetries in posterior alpha-band oscillations during an auditory retroactive cueing task, we aimed at differentiating those mechanisms. Participants were cued to attend two out of three sounds in an upcoming sound array. Importantly, the resulting working memory representation contained one laterally and one centrally presented item. A centrally presented retro-cue then indicated the lateral, the central, or both items as further relevant for the task (comparing the cued item(s) to a memory probe). Time-frequency analysis revealed opposing patterns of alpha lateralization depending on target eccentricity: A contralateral decrease in alpha power in target lateral trials indicated the involvement of target prioritization. A contralateral increase in alpha power when the central item remained relevant (distractor lateral trials) suggested the de-prioritization of irrelevant information. No lateralization was observed when both items remained relevant, supporting the notion that auditory alpha lateralization is restricted to situations in which spatial information is task-relevant. Altogether, the data demonstrate that retroactive attentional deployment involves excitatory and inhibitory control mechanisms.

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Controlling the flow of interruption in working memory

10.1101/2020.09.08.288027 ◽

2020 ◽

Author(s):

Nicole Hakim ◽

Tobias Feldmann-Wüstefeld ◽

Edward Awh ◽

Edward K Vogel

Keyword(s):

Working Memory ◽

Spatial Attention ◽

Attentional Capture ◽

Attentional Control ◽

Relevant Information ◽

Alpha Power ◽

Control Mechanisms ◽

New Information ◽

Contralateral Delay Activity ◽

Component Processes

AbstractVisual working memory (WM) must maintain relevant information, despite the constant influx of both relevant and irrelevant information. Attentional control mechanisms help determine which of this new information gets access to our capacity-limited WM system. Previous work has treated attentional control as a monolithic process–either distractors capture attention or they are suppressed. Here, we provide evidence that attentional capture may instead be broken down into at least two distinct sub-component processes: 1) spatial capture, which refers to when spatial attention shifts towards the location of irrelevant stimuli, and 2) item-based capture, which refers to when item-based WM representations of irrelevant stimuli are formed. To dissociate these two sub-component processes of attentional capture, we utilized a series of EEG components that track WM maintenance (contralateral delay activity), suppression (distractor positivity), item individuation (N2pc), and spatial attention (lateralized alpha power). We show that relevant interrupters trigger both spatial and item-based capture, which means that they undermine WM maintenance more. Irrelevant interrupters, however, only trigger spatial capture from which ongoing WM representations can recover more easily. This fractionation of attentional capture into distinct sub-component processes provides a framework by which the fate of ongoing WM processes after interruption can be explained.

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Distinct profiles of stimulus specific cortical activity for ignoring distraction during working memory encoding and maintenance, and associations with performance

10.21203/rs.3.rs-49061/v1 ◽

2020 ◽

Author(s):

Charlotte Ashton ◽

André Gouws ◽

Marcus Glennon ◽

THEODORE ZANTO ◽

Steve Tipper ◽

...

Keyword(s):

Working Memory ◽

Individual Differences ◽

Relevant Information ◽

Cortical Activity ◽

Irrelevant Information ◽

Neural Mechanisms ◽

Memory Encoding ◽

Different Types ◽

Short Time

Abstract Our ability to hold information in mind for a short time (working memory) is separately predicted by our ability to ignore two types of distraction: distraction that occurs while we put information into working memory (encoding) and distraction that occurs while we maintain already encoded information within working memory. This suggests that ignoring these different types of distraction involves distinct mechanisms which separately limit performance. Here we used fMRI to measure category-sensitive cortical activity and probe these mechanisms. The results reveal speciﬁc neural mechanisms by which relevant information is remembered and irrelevant information is ignored, which contribute to intra-individual differences in WM performance.

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Early Auditory Evoked Potential Is Modulated by Selective Attention and Related to Individual Differences in Visual Working Memory Capacity

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_00684 ◽

2014 ◽

Vol 26 (12) ◽

pp. 2682-2690 ◽

Cited By ~ 28

Author(s):

Ryan J. Giuliano ◽

Christina M. Karns ◽

Helen J. Neville ◽

Steven A. Hillyard

Keyword(s):

Working Memory ◽

Individual Differences ◽

Selective Attention ◽

Working Memory Capacity ◽

Relevant Information ◽

Auditory Evoked Potential ◽

Control Mechanisms ◽

Auditory Selective Attention ◽

Visual Change Detection ◽

Listening Task

A growing body of research suggests that the predictive power of working memory (WM) capacity for measures of intellectual aptitude is due to the ability to control attention and select relevant information. Crucially, attentional mechanisms implicated in controlling access to WM are assumed to be domain-general, yet reports of enhanced attentional abilities in individuals with larger WM capacities are primarily within the visual domain. Here, we directly test the link between WM capacity and early attentional gating across sensory domains, hypothesizing that measures of visual WM capacity should predict an individual's capacity to allocate auditory selective attention. To address this question, auditory ERPs were recorded in a linguistic dichotic listening task, and individual differences in ERP modulations by attention were correlated with estimates of WM capacity obtained in a separate visual change detection task. Auditory selective attention enhanced ERP amplitudes at an early latency (ca. 70–90 msec), with larger P1 components elicited by linguistic probes embedded in an attended narrative. Moreover, this effect was associated with greater individual estimates of visual WM capacity. These findings support the view that domain-general attentional control mechanisms underlie the wide variation of WM capacity across individuals.

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Perturbing Neural Representations of Working Memory with Task-irrelevant Interruption

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_01481 ◽

2020 ◽

Vol 32 (3) ◽

pp. 558-569 ◽

Cited By ~ 3

Author(s):

Nicole Hakim ◽

Tobias Feldmann-Wüstefeld ◽

Edward Awh ◽

Edward K. Vogel

Keyword(s):

Working Memory ◽

Memory Task ◽

Relevant Information ◽

Alpha Power ◽

Neural Signals ◽

Neural Representations ◽

Contralateral Delay Activity ◽

The Face ◽

Task Irrelevant ◽

The Impact

Working memory maintains information so that it can be used in complex cognitive tasks. A key challenge for this system is to maintain relevant information in the face of task-irrelevant perturbations. Across two experiments, we investigated the impact of task-irrelevant interruptions on neural representations of working memory. We recorded EEG activity in humans while they performed a working memory task. On a subset of trials, we interrupted participants with salient but task-irrelevant objects. To track the impact of these task-irrelevant interruptions on neural representations of working memory, we measured two well-characterized, temporally sensitive EEG markers that reflect active, prioritized working memory representations: the contralateral delay activity and lateralized alpha power (8–12 Hz). After interruption, we found that contralateral delay activity amplitude momentarily sustained but was gone by the end of the trial. Lateralized alpha power was immediately influenced by the interrupters but recovered by the end of the trial. This suggests that dissociable neural processes contribute to the maintenance of working memory information and that brief irrelevant onsets disrupt two distinct online aspects of working memory. In addition, we found that task expectancy modulated the timing and magnitude of how these two neural signals responded to task-irrelevant interruptions, suggesting that the brain's response to task-irrelevant interruption is shaped by task context.

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The impact of retro-cue validity on working memory representation: Evidence from electroencephalograms

10.31234/osf.io/nmcax ◽

2020 ◽

Author(s):

Xueying Fu ◽

Chaoxiong Ye ◽

huzhonghua ◽

Tengfei Liang ◽

Ziyuan Li ◽

...

Keyword(s):

Working Memory ◽

Spatial Attention ◽

Memory Storage ◽

Time Interval ◽

Memory Representation ◽

Attention And Memory ◽

Alpha Power ◽

Cue Validity ◽

Validity Condition ◽

The Impact

Memory performance can be improved by retrospectively cueing an item maintained in visual working memory (VWM). Different hypotheses have been proposed to explain the mechanisms behind retro-cueing and VWM. Previous behavioral studies suggest that different retro-cue validities may lead individuals to implement retro-cues in different ways to obtain a retro-cue effect. However, there is still no clear electroencephalogram (EEG) evidence to support that the retro-cue effect under different validity conditions is triggered by different mechanisms. Herein, we investigated whether retro-cue validity modulated the mechanisms underlying the retro-cue effect in VWM by using EEGs. We manipulated retro-cue validity by using blocks in a color change detection task. Contralateral delay activity (CDA) and lateralized alpha power were used assess spatial attention and memory storage, respectively. Significant retro-cue effects were observed under both high- and low-validity conditions. More importantly, although the retro-cue could redirect spatial attention under both high- and low-validity conditions, we found that participants maintained the non-cued items during a measured time interval under the low-validity condition, but dropped them out of VWM under the high-validity condition. Our results resolve previous contradictory findings. The retro-cue effect in our study can be explained by the removal hypothesis, prioritization hypothesis, and protection-during-retrieval hypothesis. This work suggests that the mechanisms underlying the retro-cue effect are not mutually exclusive, but determined by the cue validity. Individuals can voluntarily choose different mechanisms based on the expected retro-cue validity.

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Spatiotemporal Oscillatory Patterns During Working Memory Maintenance in Mild Cognitive Impairment and Subjective Cognitive Decline

International Journal of Neural Systems ◽

10.1142/s0129065719500199 ◽

2019 ◽

Vol 30 (01) ◽

pp. 1950019

Author(s):

N. Serrano ◽

D. López-Sanz ◽

R. Bruña ◽

P. Garcés ◽

I. C. Rodríguez-Rojo ◽

...

Keyword(s):

Working Memory ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Cognitive Decline ◽

Subjective Cognitive Decline ◽

Alpha Power ◽

Time Frequency ◽

Neuronal Processes ◽

Cortical Regions ◽

Local Synchronization

Working memory (WM) is a crucial cognitive process and its disruption is among the earliest symptoms of Alzheimer’s disease. While alterations of the neuronal processes underlying WM have been evidenced in mild cognitive impairment (MCI), scarce literature is available in subjective cognitive decline (SCD). We used magnetoencephalography during a WM task performed by MCI [Formula: see text], SCD [Formula: see text] and healthy elders [Formula: see text] to examine group differences during the maintenance period (0–4000[Formula: see text]ms). Data were analyzed using time–frequency analysis and significant oscillatory differences were localized at the source level. Our results indicated significant differences between groups, mainly during the early maintenance (250–1250[Formula: see text]ms) in the theta, alpha and beta bands and in the late maintenance (2750–3750[Formula: see text]ms) in the theta band. MCI showed lower local synchronization in fronto-temporal cortical regions in the early theta–alpha window relative to controls [Formula: see text] and SCD [Formula: see text], and in the late theta window relative to controls [Formula: see text] and SCD [Formula: see text]. Early theta–alpha power was significantly correlated with memory scores [Formula: see text] and late theta power was correlated with task performance [Formula: see text] and functional activity scores [Formula: see text]. In the early beta window, MCI showed reduced power in temporo-posterior regions relative to controls [Formula: see text] and SCD [Formula: see text]. Our results may suggest that these alterations would reflect that memory-related networks are damaged.

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Suppression of no-longer relevant information in Working Memory: An alpha-power related mechanism?

Biological Psychology ◽

10.1016/j.biopsycho.2018.03.009 ◽

2018 ◽

Vol 135 ◽

pp. 112-116 ◽

Cited By ~ 10

Author(s):

Claudia Poch ◽

María Valdivia ◽

Almudena Capilla ◽

José Antonio Hinojosa ◽

Pablo Campo

Keyword(s):

Working Memory ◽

Relevant Information ◽

Alpha Power

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Working Memory Processes Are Mediated by Local and Long-range Synchronization of Alpha Oscillations

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_00379 ◽

2013 ◽

Vol 25 (8) ◽

pp. 1343-1357 ◽

Cited By ~ 24

Author(s):

Maite Crespo-Garcia ◽

Diego Pinal ◽

Jose L. Cantero ◽

Fernando Díaz ◽

Montserrat Zurrón ◽

...

Keyword(s):

Working Memory ◽

Long Range ◽

Alpha Phase ◽

Alpha Power ◽

Phase Synchrony ◽

Top Down ◽

Alpha Oscillations ◽

Memory Processes ◽

Time Frequency ◽

Cortical Regions

Different cortical dynamics of alpha oscillations (8–13 Hz) have been associated with increased working memory load, which have been mostly interpreted as a neural correlate of functional inhibition. This study aims at determining whether different manifestations of load-dependent amplitude and phase dynamics in the alpha band can coexist over different cortical regions. To address this question, we increased information load by manipulating the number and spatial configuration of domino spots. Time–frequency analysis of EEG source activity revealed (i) load-independent increases of both alpha power and interregional alpha-phase synchrony within task-irrelevant, posterior cortical regions and (ii) load-dependent decreases of alpha power over areas of the left pFC and bilateral posterior parietal cortex (PPC) preceded in time by load-dependent decreases of alpha-phase synchrony between the left pFC and the left PPC. The former results support the role of alpha oscillations in inhibiting irrelevant sensorimotor processing, whereas the latter likely reflect release of parietal task-relevant areas from top–down inhibition with load increase. This interpretation found further support in a significant latency shift of 15 msec from pFC to the PPC. Together, these results suggest that amplitude and phase alpha dynamics in both local and long-range cortical networks reflect different neural mechanisms of top–down control that might be crucial in mediating the different working memory processes.

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Distractor inhibition contributes to retroactive attentional orienting within working memory: Evidence by lateralized alpha oscillations in the EEG

10.1101/235069 ◽

2017 ◽

Cited By ~ 2

Author(s):

Daniel Schneider ◽

Anna Barth ◽

Henrike Haase ◽

Clayton Hickey ◽

Edmund Wascher

Keyword(s):

Working Memory ◽

Memory Representation ◽

Alpha Power ◽

Attentional Orienting ◽

Cognitive Mechanisms ◽

Storage And Retrieval ◽

Irrelevant Item ◽

Memory Representations ◽

The Cost ◽

Memory Resources

AbstractShifts of attention within mental representations based on retroactive cues (retro-cues) facilitate performance in working memory tasks. It was suggested that this retro-cue benefit is related to the concentration of working memory resources on a subset of representations, thereby improving storage and retrieval at the cost of non-cued items. However, the attentional mechanisms underlying this updating of working memory representations remain unknown. Here, we present EEG data for distinguishing between target enhancement and distractor suppression processes in the context of retroactive attentional orienting. Therefore, we used a working memory paradigm with retro-cues indicating a shift of attention to either a lateralized or non-lateralized item. There was an increase of posterior alpha power contralateral compared to ipsilateral to the irrelevant item when a non-lateralized mental representation was cued and a contralateral suppression of posterior alpha power when a lateralized item had to be selected. This suggests that both inhibition of the non-cued information and enhancement of the target representation are important features of attentional orienting within working memory. By further presenting cues to either remember or to forget a working memory representation, we give a first impression of these retroactive attentional sub-processes as two separable cognitive mechanisms.

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