Distinct bilateral prefrontal activity patterns associated with the qualitative aspect of working memory characterized by individual sensory modality dominance

Abstract Hemodialysis (HD) is associated with cognitive impairment in patients with end-stage renal disease (ESRD). However, the neural mechanism of spatial working memory (SWM) impairment in HD-ESRD patients remains unclear. We investigated the abnormal alterations in SWM-associated brain activity patterns in HD-ESRD patients using blood oxygen level-dependent functional magnetic resonance imaging (BOLD-fMRI) technique during n-back tasks. Twenty-two HD-ESRD patients and 22 well-matched controls underwent an fMRI scan while undergoing a three-load n-back tasks with different difficulty levels. Cognitive and mental states were assessed using a battery of neuropsychologic tests. The HD-ESRD patients exhibited worse memory abilities than controls. Compared with the control group, the HD-ESRD patient group showed lower accuracy and longer response time under the n-back tasks, especially in the 2-back task. The patterns of brain activation changed under different working memory loads in the HD-ESRD patients, showing decreased activity in the right medial frontal gyrus and inferior frontal gyrus under 0-back and 1-back task, while more decreased activation in the bilateral frontal cortex, parietal lobule, anterior/posterior cingulate cortex and insula cortex under 2-back task. With the increase of task difficulty, the activation degree of the frontal and parietal cortex decreased. More importantly, we found that lower activation in frontal cortex and parietal lobule was associated with worse cognitive function in the HD-ESRD patients. These results demonstrate that the abnormal brain activity patterns of frontal cortex and parietal lobule may reflect the neural mediation of SWM impairment.

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Perceptual Representations and the Vividness of Stimulus-Triggered and Stimulus-Independent Experiences

Perspectives on Psychological Science ◽

10.1177/1745691620924039 ◽

2020 ◽

Vol 15 (5) ◽

pp. 1200-1213 ◽

Cited By ~ 1

Author(s):

Peter Fazekas ◽

Georgina Nemeth ◽

Morten Overgaard

Keyword(s):

Working Memory ◽

Mental Imagery ◽

Information Exchange ◽

Activity Patterns ◽

Mind Wandering ◽

Brain Regions ◽

Neural Basis ◽

Fine Grained ◽

Common Framework ◽

Cortical Regions

In recent years, researchers from independent subfields have begun to engage with the idea that the same cortical regions that contribute to on-line perception are recruited during and underlie off-line activities such as information maintenance in working memory, mental imagery, hallucinations, dreaming, and mind wandering. Accumulating evidence suggests that in all of these cases the activity of posterior brain regions provides the contents of experiences. This article is intended to move one step further by exploring specific links between the vividness of experiences, which is a characteristic feature of consciousness regardless of its actual content, and certain properties of the content-specific neural-activity patterns. Investigating the mechanisms that underlie mental imagery and its relation to working memory and the processes responsible for mind wandering and its similarities to dreaming form two clusters of research that are in the forefront of the recent scientific study of mental phenomena, yet communication between these two clusters has been surprisingly sparse. Here our aim is to foster such information exchange by articulating a hypothesis about the fine-grained phenomenological structure determining subjective vividness and its possible neural basis that allows us to shed new light on these mental phenomena by bringing them under a common framework.

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Brain Activity Patterns in Stable and Progressive Mild Cognitive Impairment During Working Memory as Evidenced by Magnetoencephalography

Journal of Clinical Neurophysiology ◽

10.1097/wnp.0b013e3182121743 ◽

2011 ◽

Vol 28 (2) ◽

pp. 202-209 ◽

Cited By ~ 12

Author(s):

Fernando Maestú ◽

Raquel Yubero ◽

Stephan Moratti ◽

Pablo Campo ◽

Pedro Gil-Gregorio ◽

...

Keyword(s):

Working Memory ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Brain Activity ◽

Activity Patterns

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Multiple types of navigational information are independently encoded in the population activities of the dentate gyrus neurons

10.1101/2020.06.09.141572 ◽

2020 ◽

Author(s):

Tomoyuki Murano ◽

Ryuichi Nakajima ◽

Akito Nakao ◽

Nao Hirata ◽

Satoko Amemori ◽

...

Keyword(s):

Machine Learning ◽

Working Memory ◽

Dentate Gyrus ◽

Open Field ◽

Activity Patterns ◽

Spatial Coding ◽

Motion Direction ◽

Freely Moving ◽

Types Of Information ◽

Decoding Accuracy

AbstractThe dentate gyrus (DG) plays critical roles in cognitive functions such as learning, memory, and spatial coding, and its dysfunction is implicated in various neuropsychiatric disorders. However, it remains largely unknown how information is represented in this region. Here, we recorded neuronal activity in the DG using Ca2+ imaging in freely moving mice and analysed this activity using machine learning. The activity patterns of populations of DG neurons enabled us to successfully decode position, speed, and motion direction in an open field as well as current and future location in a T-maze, and each individual neuron was diversely and independently tuned to these multiple information types. In αCaMKII heterozygous knockout mice, which present deficits in spatial remote and working memory, the decoding accuracy of position in the open field and future location in the T-maze were selectively reduced. These results suggest that multiple types of information are independently distributed in DG neurons.

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Highly task-specific and distributed neural connectivity in working memory revealed by single-trial decoding in mice and humans

10.1101/2021.04.20.440621 ◽

2021 ◽

Author(s):

Daniel Strahnen ◽

Sampath K.T. Kapanaiah ◽

Alexei M. Bygrave ◽

Birgit Liss ◽

David M. Bannerman ◽

...

Keyword(s):

Working Memory ◽

Activity Patterns ◽

Brain Regions ◽

Cognitive Domain ◽

Neural Connectivity ◽

Task Specificity ◽

Electrophysiological Recordings ◽

Connectivity Patterns ◽

Unbiased Manner ◽

Beta Frequency

AbstractWorking memory (WM), the capacity to briefly and intentionally maintain mental items, is key to successful goal-directed behaviour and impaired in a range of psychiatric disorders. To date, several brain regions, connections, and types of neural activity have been correlatively associated with WM performance. However, no unifying framework to integrate these findings exits, as the degree of their species- and task-specificity remains unclear. Here, we investigate WM correlates in three task paradigms each in mice and humans, with simultaneous multi-site electrophysiological recordings. We developed a machine learning-based approach to decode WM-mediated choices in individual trials across subjects from hundreds of electrophysiological measures of neural connectivity with up to 90% prediction accuracy. Relying on predictive power as indicator of correlates of psychological functions, we unveiled a large number of task phase-specific WM-related connectivity from analysis of predictor weights in an unbiased manner. Only a few common connectivity patterns emerged across tasks. In rodents, these were thalamus-prefrontal cortex delta- and beta-frequency connectivity during memory encoding and maintenance, respectively, and hippocampal-prefrontal delta- and theta-range coupling during retrieval, in rodents. In humans, task-independent WM correlates were exclusively in the gamma-band. Mostly, however, the predictive activity patterns were unexpectedly specific to each task and always widely distributed across brain regions. Our results suggest that individual tasks cannot be used to uncover generic physiological correlates of the psychological construct termed WM and call for a new conceptualization of this cognitive domain in translational psychiatry.

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Sensory-modality independent activation of the brain network for language

10.1101/714998 ◽

2019 ◽

Author(s):

Sophie Arana ◽

André Marquand ◽

Annika Hultén ◽

Peter Hagoort ◽

Jan-Mathijs Schoffelen

Keyword(s):

Language Processing ◽

Sentence Processing ◽

Human Subjects ◽

Brain Activity ◽

Activity Patterns ◽

Sensory Modality ◽

Brain Network ◽

Large Network ◽

Individual Subject ◽

The Brain

AbstractThe meaning of a sentence can be understood, whether presented in written or spoken form. Therefore it is highly probable that brain processes supporting language comprehension are at least partly independent of sensory modality. To identify where and when in the brain language processing is independent of sensory modality, we directly compared neuromagnetic brain signals of 200 human subjects (102 males) either reading or listening to sentences. We used multiset canonical correlation analysis to align individual subject data in a way that boosts those aspects of the signal that are common to all, allowing us to capture word-by-word signal variations, consistent across subjects and at a fine temporal scale. Quantifying this consistency in activation across both reading and listening tasks revealed a mostly left hemispheric cortical network. Areas showing consistent activity patterns include not only areas previously implicated in higher-level language processing, such as left prefrontal, superior & middle temporal areas and anterior temporal lobe, but also parts of the control-network as well as subcentral and more posterior temporal-parietal areas. Activity in this supramodal sentence processing network starts in temporal areas and rapidly spreads to the other regions involved. The findings do not only indicate the involvement of a large network of brain areas in supramodal language processing, but also indicate that the linguistic information contained in the unfolding sentences modulates brain activity in a word-specific manner across subjects.

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Effects of renal receptor activation on neurosecretory vasopressin cells

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1987.253.2.r234 ◽

1987 ◽

Vol 253 (2) ◽

pp. R234-R241 ◽

Cited By ~ 5

Author(s):

T. A. Day ◽

J. Ciriello

Keyword(s):

Hormonal Regulation ◽

Activity Patterns ◽

Sensory Modality ◽

Arterial Occlusion ◽

Venous Occlusion ◽

Receptor Activation ◽

Systemic Arterial Pressure ◽

Renal Nerves ◽

Cell Discharge ◽

Renal Receptor

Electrical stimulation of afferent renal nerves (ARN) has been shown to excite neurosecretory vasopressin (AVP) cells of the supraoptic nucleus (SON). To investigate the sensory modality of the ARN involved, the present study examined in pentobarbital-anesthetized rats the responses of putative AVP cells to procedures intended to differentially activate renal receptor populations. Neurosecretory SON cells were identified by antidromic invasion from the neurohypophysis and classified as AVP secreting on the basis of spontaneous activity patterns and responses to arterial baroreceptor activation. Neither elevation of systemic arterial pressure (50-100 mmHg, 9 cells) following sinoaortic and cardiopulmonary afferent nerve transection nor renal venous occlusion (15 cells) altered AVP cell discharge. Renal ischemia, produced by renal arterial occlusion (50-120 s, 14 cells), and renal arterial infusion of adenosine (1-50 micrograms, 8 cells) were also without effect. However, infusions into the renal artery of bradykinin (1-3 micrograms) excited 9/15, of capsaicin (1-3 micrograms) excited 13/15, and of sodium cyanide (5-40 micrograms) excited 1/11 AVP cells examined. These data demonstrate that, in the anesthetized rat, putative neurosecretory AVP cells in the SON are responsive to activation of bradykinin- and capsaicin-sensitive renal receptors and suggest that activation of these receptors contributes to the hormonal regulation of the circulation.

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Distributed and Dynamic Storage of Working Memory Stimulus Information in Extrastriate Cortex

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_00556 ◽

2014 ◽

Vol 26 (5) ◽

pp. 1141-1153 ◽

Cited By ~ 48

Author(s):

Kartik K. Sreenivasan ◽

Jason Vytlacil ◽

Mark D'Esposito

Keyword(s):

Working Memory ◽

Activity Patterns ◽

Canonical Model ◽

Extrastriate Cortex ◽

Stimulus Information ◽

Population Activity ◽

Sensory Representation ◽

Neural Populations ◽

Elevated Activity ◽

Dynamic Storage

The predominant neurobiological model of working memory (WM) posits that stimulus information is stored via stable, elevated activity within highly selective neurons. On the basis of this model, which we refer to as the canonical model, the storage of stimulus information is largely associated with lateral PFC (lPFC). A growing number of studies describe results that cannot be fully explained by the canonical model, suggesting that it is in need of revision. In this study, we directly tested key elements of the canonical model. We analyzed fMRI data collected as participants performed a task requiring WM for faces and scenes. Multivariate decoding procedures identified patterns of activity containing information about the items maintained in WM (faces, scenes, or both). Although information about WM items was identified in extrastriate visual cortex (EC) and lPFC, only EC exhibited a pattern of results consistent with a sensory representation. Information in both regions persisted even in the absence of elevated activity, suggesting that elevated population activity may not represent the storage of information in WM. Additionally, we observed that WM information was distributed across EC neural populations that exhibited a broad range of selectivity for the WM items rather than restricted to highly selective EC populations. Finally, we determined that activity patterns coding for WM information were not stable, but instead varied over the course of a trial, indicating that the neural code for WM information is dynamic rather than static. Together, these findings challenge the canonical model of WM.

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The Role of Anterior Cingulate Cortex in Working Memory is Shaped by Functional Connectivity

Journal of Cognitive Neuroscience ◽

10.1162/0898929054475127 ◽

2005 ◽

Vol 17 (7) ◽

pp. 1026-1042 ◽

Cited By ~ 56

Author(s):

Agatha Lenartowicz ◽

Anthony R. McIntosh

Keyword(s):

Working Memory ◽

Functional Connectivity ◽

Memory Performance ◽

Activity Patterns ◽

Standard Condition ◽

Memory Task ◽

Anterior Cingulate ◽

Connectivity Pattern ◽

Attention And Memory ◽

Speed Accuracy

The anterior cingulate (AC) cortex seems to be similarly engaged by attentional and memory processes. We tested the hypothesis that this common activation is best explained by changes in the regions interacting (functionally connected) with AC. Subjects were tested on two variants of a 2-back working memory task: a standard version with strong attentional demands, and a cued version that more strongly promoted memory retrieval. AC activation, measured with functional MRI, was found in both tasks, although more sustained in the standard condition. The regions functionally connected to the AC, and the relation of these activity patterns to memory performance, were completely different across tasks. In the standard task, the pattern related to a speed-accuracy tradeoff, whereas the connectivity pattern unique to the cued task related only to better accuracy. By virtue of these changing patterns of functional connectivity, the contribution of AC to attention-and memory-driven performance was similarly changed.

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How Human Single-Neuron Recordings Can Help Us Understand Cognition: Insights from Memory Studies

Brain Sciences ◽

10.3390/brainsci11040443 ◽

2021 ◽

Vol 11 (4) ◽

pp. 443

Author(s):

Zuzanna Roma Kubska ◽

Jan Kamiński

Keyword(s):

Working Memory ◽

Animal Studies ◽

Single Neuron ◽

Activity Patterns ◽

Memory Studies ◽

Human Cognition ◽

Persistent Activity ◽

Full Understanding ◽

Future Directions ◽

Cognitive Theories

Understanding human cognition is a key goal of contemporary neuroscience. Due to the complexity of the human brain, animal studies and noninvasive techniques, however valuable, are incapable of providing us with a full understanding of human cognition. In the light of existing cognitive theories, we describe findings obtained thanks to human single-neuron recordings, including the discovery of concept cells and novelty-dependent cells, or activity patterns behind working memory, such as persistent activity. We propose future directions for studies using human single-neuron recordings and we discuss possible opportunities of investigating pathological brain.

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