Involvement of visual cortex in a visual working memory task: Evidence from steady-state visual potential frequency tagging

AbstractWorking memory and episodic memory are two different processes, although the nature of their interrelationship is debated. As these processes are predominantly studied in isolation, it is unclear whether they crucially rely on different neural substrates. To obtain more insight in this, 81 adults with sub-acute ischemic stroke and 29 elderly controls were assessed on a visual working memory task, followed by a surprise subsequent memory test for the same stimuli. Multivariate, atlas- and track-based lesion-symptom mapping (LSM) analyses were performed to identify anatomical correlates of visual memory. Behavioral results gave moderate evidence for independence between discriminability in working memory and subsequent memory, and strong evidence for a correlation in response bias on the two tasks in stroke patients. LSM analyses suggested there might be independent regions associated with working memory and episodic memory. Lesions in the right arcuate fasciculus were more strongly associated with discriminability in working memory than in subsequent memory, while lesions in the frontal operculum in the right hemisphere were more strongly associated with criterion setting in subsequent memory. These findings support the view that some processes involved in working memory and episodic memory rely on separate mechanisms, while acknowledging that there might also be shared processes.

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Anatomy of early visual cortex predicts visual working memory capacity

Journal of Vision ◽

10.1167/13.9.1349 ◽

2013 ◽

Vol 13 (9) ◽

pp. 1349-1349

Author(s):

J. Bergmann ◽

E. Genc ◽

A. Kohler ◽

W. Singer ◽

J. Pearson

Keyword(s):

Working Memory ◽

Visual Cortex ◽

Visual Working Memory ◽

Working Memory Capacity ◽

Memory Capacity ◽

Early Visual Cortex

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The Neural Codes Underlying Internally Generated Representations in Visual Working Memory

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_01702 ◽

2021 ◽

pp. 1-16

Author(s):

Qing Yu ◽

Bradley R. Postle

Keyword(s):

Working Memory ◽

Visual Cortex ◽

Visual Working Memory ◽

Subjective Experience ◽

Neural Representation ◽

Delayed Recall ◽

Early Visual Cortex ◽

Memory Representations ◽

Internal Sources ◽

Scaling Analyses

Abstract Humans can construct rich subjective experience even when no information is available in the external world. Here, we investigated the neural representation of purely internally generated stimulus-like information during visual working memory. Participants performed delayed recall of oriented gratings embedded in noise with varying contrast during fMRI scanning. Their trialwise behavioral responses provided an estimate of their mental representation of the to-be-reported orientation. We used multivariate inverted encoding models to reconstruct the neural representations of orientation in reference to the response. We found that response orientation could be successfully reconstructed from activity in early visual cortex, even on 0% contrast trials when no orientation information was actually presented, suggesting the existence of a purely internally generated neural code in early visual cortex. In addition, cross-generalization and multidimensional scaling analyses demonstrated that information derived from internal sources was represented differently from typical working memory representations, which receive influences from both external and internal sources. Similar results were also observed in intraparietal sulcus, with slightly different cross-generalization patterns. These results suggest a potential mechanism for how externally driven and internally generated information is maintained in working memory.

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The limited contribution of early visual cortex in visual working memory for surface roughness

10.31234/osf.io/ys3a5 ◽

2020 ◽

Author(s):

Munendo Fujimichi ◽

Hiroki Yamamoto ◽

Jun Saiki

Keyword(s):

Working Memory ◽

Visual Cortex ◽

Visual Working Memory ◽

Brain Activity ◽

Visual Representations ◽

Brain Regions ◽

Daily Lives ◽

Early Visual Cortex ◽

Roughness Discrimination ◽

Visual Properties

Are visual representations in the human early visual cortex necessary for visual working memory (VWM)? Previous studies suggest that VWM is underpinned by distributed representations across several brain regions, including the early visual cortex. Notably, in these studies, participants had to memorize images under consistent visual conditions. However, in our daily lives, we must retain the essential visual properties of objects despite changes in illumination or viewpoint. The role of brain regions—particularly the early visual cortices—in these situations remains unclear. The present study investigated whether the early visual cortex was essential for achieving stable VWM. Focusing on VWM for object surface properties, we conducted fMRI experiments while male and female participants performed a delayed roughness discrimination task in which sample and probe spheres were presented under varying illumination. By applying multi-voxel pattern analysis to brain activity in regions of interest, we found that the ventral visual cortex and intraparietal sulcus were involved in roughness VWM under changing illumination conditions. In contrast, VWM was not supported as robustly by the early visual cortex. These findings show that visual representations in the early visual cortex alone are insufficient for the robust roughness VWM representation required during changes in illumination.

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The influence of visual working memory representations on attention bias to threat in individuals with high trait anxiety

Journal of Experimental Psychopathology ◽

10.1177/2043808719876149 ◽

2019 ◽

Vol 10 (4) ◽

pp. 204380871987614

Author(s):

Nisha Yao ◽

Marcus A. Rodriguez ◽

Mengyao He ◽

Mingyi Qian

Keyword(s):

Working Memory ◽

Visual Working Memory ◽

Experimental Studies ◽

Memory Task ◽

Attention Bias ◽

Control Group ◽

Negative Valence ◽

Memory Representations ◽

High Trait Anxiety ◽

The Relationship

Experimental studies have yielded discrepant results regarding the relationship between anxiety and attention bias to threat. Cognitive factors modulating the presence of threat-related attention bias in anxiety have drawn growing attention. Previous research demonstrated that visual working memory (WM) representations can guide attention allocation in a top-down manner. Whether threat-related WM representations affected the presence of attention bias in anxiety awaits examination. Combining a memory task and a dot-probe task, this study investigated how WM representations of faces with neutral or negative expressions modulated the attention bias to threat among highly anxious individuals versus controls. Results showed that highly anxious individuals developed more pronounced attention bias to threat when maintaining WM representations of negative faces as compared to the control group. There were no significant between-group effects when the WM representations were neutral. These results suggested that highly anxious individuals were more susceptible to the influence of mental representations with negative valence on attention deployment.

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Auditory and Visual Working Memory Are Differentially Related to Carotenoid Status in Preadolescent Children

Current Developments in Nutrition ◽

10.1093/cdn/nzaa041_002 ◽

2020 ◽

Vol 4 (Supplement_2) ◽

pp. 98-98

Author(s):

Corinne Cannavale ◽

Caitlyn Edwards ◽

Ruyu Liu ◽

Samantha Iwinski ◽

Anne Walk ◽

...

Keyword(s):

Working Memory ◽

Visual Working Memory ◽

Cognitive Abilities ◽

Memory Function ◽

Memory Task ◽

Whole Body ◽

Set Size ◽

Preadolescent Children ◽

Central Illinois ◽

The Relationship

Abstract Objectives Carotenoids are plant pigments known to deposit in neural tissues including the hippocampus, a brain substrate that supports several memory forms. However, there is a dearth of knowledge regarding carotenoid status and working memory function in children. Accordingly, this study aimed to understand the relationship between macular and skin carotenoids to visual and auditory working memory (WM) function. Methods Seventy preadolescent children (7–12 years, 32 males) were recruited from the East-Central Illinois area. Auditory working memory was assessed using the story recall subtest of the Woodcock-Johnson IV Test of Cognitive Abilities. A subsample (N = 61, 27 males) completed a visual working memory task and reaction time was quantified to determine speed of memory processing at set sizes of 1 to 4 items. Macular pigment optical density (MPOD) was assessed using customized heterochromatic flicker photometry. Skin carotenoids were assessed using reflection spectroscopy (Veggie Meter). Hierarchical linear regressions were conducted to assess the relationship between carotenoid status and WM function, while controlling for age, sex, income, and whole-body % fat (DXA). Results Auditory WM was positively associated with skin carotenoids (b = 0.263, P = 0.039) but not MPOD (b = −0.044, P = 0.380). In contrast, MPOD was significantly associated with faster visual WM speed at set size 3 (b = −0.253, P = 0.039) and trending at set sizes of 1 (b = −0.225, P = 0.051), 2 (b = −0.171, P = 0.121), and 4 (b = −0.230, P = 0.055). Interestingly, skin carotenoids were not related to visual WM performance at either set size (all P’s > 0.300). Conclusions These results indicate that auditory and visual WM may be differentially related to carotenoids. While skin carotenoids encompass all carotenoids consumed in diet, lutein and zeaxanthin are the only carotenoids which deposit in the macula. Given that MPOD was only related to visual WM, this suggests lutein plays a larger role in these neural functions relative to auditory WM. Interestingly, MPOD's relationship with visual WM increased in strength with the more difficult trial type (i.e., increasing set size), indicating MPOD is related at higher levels of WM capacity. Funding Sources This study was funded by the Egg Nutrition Center.

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Tracking stimulus representation across a 2-back visual working memory task

Royal Society Open Science ◽

10.1098/rsos.190228 ◽

2020 ◽

Vol 7 (8) ◽

pp. 190228 ◽

Cited By ~ 2

Author(s):

Quan Wan ◽

Ying Cai ◽

Jason Samaha ◽

Bradley R. Postle

Keyword(s):

Working Memory ◽

Visual Working Memory ◽

Memory Task ◽

Memory Item ◽

Neural Representation ◽

Stimulus Representation ◽

Representational Format ◽

The Status ◽

Memory Content ◽

Default Assumption

How does the neural representation of visual working memory content vary with behavioural priority? To address this, we recorded electroencephalography (EEG) while subjects performed a continuous-performance 2-back working memory task with oriented-grating stimuli. We tracked the transition of the neural representation of an item ( n ) from its initial encoding, to the status of ‘unprioritized memory item' (UMI), and back to ‘prioritized memory item', with multivariate inverted encoding modelling. Results showed that the representational format was remapped from its initially encoded format into a distinctive ‘opposite' representational format when it became a UMI and then mapped back into its initial format when subsequently prioritized in anticipation of its comparison with item n + 2. Thus, contrary to the default assumption that the activity representing an item in working memory might simply get weaker when it is deprioritized, it may be that a process of priority-based remapping helps to protect remembered information when it is not in the focus of attention.

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