Linking the Rapid Cascade of Visuo-Attentional Processes to Successful Memory Encoding

Abstract While it is broadly accepted that attention modulates memory, the contribution of specific rapid attentional processes to successful encoding is largely unknown. To investigate this issue, we leveraged the high temporal resolution of electroencephalographic recordings to directly link a cascade of visuo-attentional neural processes to successful encoding: namely (1) the N2pc (peaking ~200 ms), which reflects stimulus-specific attentional orienting and allocation, (2) the sustained posterior-contralateral negativity (post-N2pc), which has been associated with sustained visual processing, (3) the contralateral reduction in oscillatory alpha power (contralateral reduction in alpha > 200 ms), which has also been independently related to attentionally sustained visual processing. Each of these visuo-attentional processes was robustly predictive of successful encoding, and, moreover, each enhanced memory independently of the classic, longer-latency, conceptually related, difference-due-to memory (Dm) effect. Early latency midfrontal theta power also promoted successful encoding, with at least part of this influence being mediated by the later latency Dm effect. These findings markedly expand current knowledge by helping to elucidate the intimate relationship between attentional modulations of perceptual processing and effective encoding for later memory retrieval.

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Exploring the Electrophysiological Correlates of Encoding Retractions of Misinformation

10.31234/osf.io/e2zaq ◽

2018 ◽

Author(s):

Christopher Brydges ◽

Andrew Gordon ◽

Ullrich K. H. Ecker

Keyword(s):

Temporal Resolution ◽

Event Related Potential ◽

Future Research ◽

High Temporal Resolution ◽

Memory Encoding ◽

Bayesian Analyses ◽

Neural Processes ◽

Behavioural Research ◽

Corrective Information ◽

With Memory

A plethora of behavioural research has suggested that the successful encoding of retracting information is required to minimise the lingering effects of misinformation. However, neuroscientific research in this area is much scarcer. Participants (n = 34) completed a typical continued-influence misinformation paradigm whilst electroencephalographic data were recorded. Two event-related potential (ERP) components associated with memory encoding and updating (a left-frontal positivity and the parietal P3b) were examined when participants processed misinformation retractions in comparison to when no misinformation was presented. Neither frequentist nor Bayesian analyses found differences between ERP amplitudes elicited by retractions and non-retractions. It is plausible that misinformation removal and the integration of corrective information are not temporally reliable across trials, resulting in suppressed amplitude in the ERP. Nonetheless, the high temporal resolution of ERPs may still be able to provide an informative perspective on the neural processes of misinformation processing in future research.

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Neural Dynamics of Cognitive Control over Working Memory Capture of Attention

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_01409 ◽

2019 ◽

Vol 31 (7) ◽

pp. 1079-1090 ◽

Cited By ~ 2

Author(s):

Peter S. Whitehead ◽

Mathilde M. Ooi ◽

Tobias Egner ◽

Marty G. Woldorff

Keyword(s):

Working Memory ◽

Visual Search ◽

Cognitive Control ◽

Attentional Capture ◽

Search Display ◽

Neural Mechanisms ◽

High Temporal Resolution ◽

Control Mechanisms ◽

Attentional Orienting ◽

Behavioral Studies

The contents of working memory (WM) guide visual attention toward matching features, with visual search being faster when the target and a feature of an item held in WM spatially overlap (validly cued) than when they occur at different locations (invalidly cued). Recent behavioral studies have indicated that attentional capture by WM content can be modulated by cognitive control: When WM cues are reliably helpful to visual search (predictably valid), capture is enhanced, but when reliably detrimental (predictably invalid), capture is attenuated. The neural mechanisms underlying this effect are not well understood, however. Here, we leveraged the high temporal resolution of ERPs time-locked to the onset of the search display to determine how and at what processing stage cognitive control modulates the search process. We manipulated predictability by grouping trials into unpredictable (50% valid/invalid) and predictable (100% valid, 100% invalid) blocks. Behavioral results confirmed that predictability modulated WM-related capture. Comparison of ERPs to the search arrays showed that the N2pc, a posteriorly distributed signature of initial attentional orienting toward a lateralized target, was not impacted by target validity predictability. However, a longer latency, more anterior, lateralized effect—here, termed the “contralateral attention-related negativity”—was reduced under predictable conditions. This reduction interacted with validity, with substantially greater reduction for invalid than valid trials. These data suggest cognitive control over attentional capture by WM content does not affect the initial attentional-orienting process but can reduce the need to marshal later control mechanisms for processing relevant items in the visual world.

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Critical Flicker Fusion Frequency: A Narrative Review

Medicina ◽

10.3390/medicina57101096 ◽

2021 ◽

Vol 57 (10) ◽

pp. 1096

Author(s):

Natalia D. Mankowska ◽

Anna B. Marcinkowska ◽

Monika Waskow ◽

Rita I. Sharma ◽

Jacek Kot ◽

...

Keyword(s):

Visual Processing ◽

Current Knowledge ◽

Minimal Hepatic Encephalopathy ◽

Future Research ◽

Critical Flicker Fusion ◽

Flicker Fusion Frequency ◽

Fusion Frequency ◽

Critical Flicker Fusion Frequency ◽

Model Studies ◽

Flicker Fusion

This review presents the current knowledge of the usage of critical flicker fusion frequency (CFF) in human and animal model studies. CFF has a wide application in different fields, especially as an indicator of cortical arousal and visual processing. In medicine, CFF may be helpful for diagnostic purposes, for example in epilepsy or minimal hepatic encephalopathy. Given the environmental studies and a limited number of other methods, it is applicable in diving and hyperbaric medicine. Current research also shows the relationship between CFF and other electrophysiological methods, such as electroencephalography. The human eye can detect flicker at 50–90 Hz but reports are showing the possibility to distinguish between steady and modulated light up to 500 Hz. Future research with the use of CFF is needed to better understand its utility and application.

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Neural correlates of the LSD experience revealed by multimodal neuroimaging

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1518377113 ◽

2016 ◽

Vol 113 (17) ◽

pp. 4853-4858 ◽

Cited By ~ 248

Author(s):

Robin L. Carhart-Harris ◽

Suresh Muthukumaraswamy ◽

Leor Roseman ◽

Mendel Kaelen ◽

Wouter Droog ◽

...

Keyword(s):

Visual Cortex ◽

Visual Processing ◽

Brain Activity ◽

Blood Oxygen Level Dependent ◽

Retrosplenial Cortex ◽

Alpha Power ◽

Blood Oxygen Level ◽

Psychedelic Drugs ◽

Cortex Cérébral ◽

Intrinsic Brain Activity

Lysergic acid diethylamide (LSD) is the prototypical psychedelic drug, but its effects on the human brain have never been studied before with modern neuroimaging. Here, three complementary neuroimaging techniques: arterial spin labeling (ASL), blood oxygen level-dependent (BOLD) measures, and magnetoencephalography (MEG), implemented during resting state conditions, revealed marked changes in brain activity after LSD that correlated strongly with its characteristic psychological effects. Increased visual cortex cerebral blood flow (CBF), decreased visual cortex alpha power, and a greatly expanded primary visual cortex (V1) functional connectivity profile correlated strongly with ratings of visual hallucinations, implying that intrinsic brain activity exerts greater influence on visual processing in the psychedelic state, thereby defining its hallucinatory quality. LSD’s marked effects on the visual cortex did not significantly correlate with the drug’s other characteristic effects on consciousness, however. Rather, decreased connectivity between the parahippocampus and retrosplenial cortex (RSC) correlated strongly with ratings of “ego-dissolution” and “altered meaning,” implying the importance of this particular circuit for the maintenance of “self” or “ego” and its processing of “meaning.” Strong relationships were also found between the different imaging metrics, enabling firmer inferences to be made about their functional significance. This uniquely comprehensive examination of the LSD state represents an important advance in scientific research with psychedelic drugs at a time of growing interest in their scientific and therapeutic value. The present results contribute important new insights into the characteristic hallucinatory and consciousness-altering properties of psychedelics that inform on how they can model certain pathological states and potentially treat others.

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When encodong yields remembering: insights from event-related neuroimaging

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.1999.0481 ◽

1999 ◽

Vol 354 (1387) ◽

pp. 1307-1324 ◽

Cited By ~ 147

Author(s):

Anthony D. Wagner ◽

Wilma Koutstaal ◽

Daniel L. Schacter

Keyword(s):

Neural Activity ◽

Functional Neuroimaging ◽

Event Related Potentials ◽

Human Memory ◽

Memory Encoding ◽

Positron Emission ◽

Related Potentials ◽

The Rich ◽

Dm Effect ◽

The Brain

To understand human memory, it is important to determine why some experiences are remembered whereas others are forgotten. Until recently, insights into the neural bases of human memory encoding, the processes by which information is transformed into an enduring memory trace, have primarily been derived from neuropsychological studies of humans with select brain lesions. The advent of functional neuroimaging methods, such as positron emission tomography (PET) and functional magnetic resonance imaging (fMRI), has provided a new opportunity to gain additional understanding of how the brain supports memory formation. Importantly, the recent development of event–related fMRI methods now allows for examination of trial–by–trial differences in neural activity during encoding and of the consequences of these differences for later remembering. In this review, we consider the contributions of PET and fMRI studies to the understanding of memory encoding, placing a particular emphasis on recent event–related fMRI studies of the Dm effect: that is, differences in neural activity during encoding that are related to differences in subsequent memory. We then turn our attention to the rich literature on the Dm effect that has emerged from studies using event–related potentials (ERPs). It is hoped that the integration of findings from ERP studies, which offer higher temporal resolution, with those from event–related fMRI studies, which offer higher spatial resolution, will shed new light on when and why encoding yields subsequent remembering.

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Electrophysiological signatures of memory reactivation in humans

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2019.0293 ◽

2020 ◽

Vol 375 (1799) ◽

pp. 20190293 ◽

Cited By ~ 4

Author(s):

Thomas Schreiner ◽

Tobias Staudigl

Keyword(s):

Episodic Memory ◽

Neural Activity ◽

Crucial Role ◽

Memory Retrieval ◽

Functional Significance ◽

State Of The Art ◽

Memory Reactivation ◽

Open Questions ◽

Neural Processes

The reactivation of neural activity that was present during the encoding of an event is assumed to be essential for human episodic memory retrieval and the consolidation of memories during sleep. Pioneering animal work has already established a crucial role of memory reactivation to prepare and guide behaviour. Research in humans is now delineating the neural processes involved in memory reactivation during both wakefulness and sleep as well as their functional significance. Focusing on the electrophysiological signatures of memory reactivation in humans during both memory retrieval and sleep-related consolidation, this review provides an overview of the state of the art in the field. We outline recent advances, methodological developments and open questions and specifically highlight commonalities and differences in the neuronal signatures of memory reactivation during the states of wakefulness and sleep. This article is part of the Theo Murphy meeting issue ‘Memory reactivation: replaying events past, present and future’.

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Differential Effects of Lowered Arousal on Covert and Overt Shifts of Attention

Journal of the International Neuropsychological Society ◽

10.1017/s1355617715000405 ◽

2015 ◽

Vol 21 (7) ◽

pp. 545-557 ◽

Cited By ~ 2

Author(s):

Bruno Fimm ◽

Klaus Willmes ◽

Will Spijkers

Keyword(s):

Sleep Deprivation ◽

Reaction Times ◽

Brain Structures ◽

Attentional Orienting ◽

Tight Coupling ◽

Attentional Processes ◽

Differential Effects ◽

Norepinephrine System ◽

Left And Right ◽

Healthy Participants

AbstractBased on previous studies demonstrating detrimental effects of reduced alertness on attentional orienting our study seeks to examine covert and overt attentional orienting in different arousal states. We hypothesized an attentional asymmetry with increasing reaction times to stimuli presented to the left visual field in a state of maximally reduced arousal. Eleven healthy participants underwent sleep deprivation and were examined repeatedly every 4 hr over 28 hr in total with two tasks measuring covert and overt orienting of attention. Contrary to our hypothesis, a reduction of arousal did not induce any asymmetry of overt orienting. Even in participants with profound and significant attentional asymmetries in covert orienting no substantial reaction time differences between left- and right-sided targets in the overt orienting task could be observed. This result is not in agreement with assumptions of a tight coupling of covert and overt attentional processes. In conclusion, we found differential effects of lowered arousal induced by sleep deprivation on covert and overt orienting of attention. This pattern of results points to a neuronal non-overlap of brain structures subserving these functions and a differential influence of the norepinephrine system on these modes of spatial attention. (JINS, 2015,21, 545–557)

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Defining the Units of Competition: Influences of Perceptual Organization on Competitive Interactions in Human Visual Cortex

Journal of Cognitive Neuroscience ◽

10.1162/jocn.2009.21391 ◽

2010 ◽

Vol 22 (11) ◽

pp. 2417-2426 ◽

Cited By ~ 27

Author(s):

Stephanie A. McMains ◽

Sabine Kastner

Keyword(s):

Visual Cortex ◽

Perceptual Organization ◽

Visual Processing ◽

Perceptual Grouping ◽

Neural Representation ◽

Competitive Interactions ◽

Illusory Figure ◽

Processing Stream ◽

Neural Processes ◽

Early Visual Cortex

Multiple stimuli that are present simultaneously in the visual field compete for neural representation. At the same time, however, multiple stimuli in cluttered scenes also undergo perceptual organization according to certain rules originally defined by the Gestalt psychologists such as similarity or proximity, thereby segmenting scenes into candidate objects. How can these two seemingly orthogonal neural processes that occur early in the visual processing stream be reconciled? One possibility is that competition occurs among perceptual groups rather than at the level of elements within a group. We probed this idea using fMRI by assessing competitive interactions across visual cortex in displays containing varying degrees of perceptual organization or perceptual grouping (Grp). In strong Grp displays, elements were arranged such that either an illusory figure or a group of collinear elements were present, whereas in weak Grp displays the same elements were arranged randomly. Competitive interactions among stimuli were overcome throughout early visual cortex and V4, when elements were grouped regardless of Grp type. Our findings suggest that context-dependent grouping mechanisms and competitive interactions are linked to provide a bottom–up bias toward candidate objects in cluttered scenes.

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