scholarly journals Real-time cognitive performance and positive symptom expression in schizophrenia

2021 ◽  
Author(s):  
Maud Dupuy ◽  
Majd Abdallah ◽  
Joel Swendsen ◽  
Bernard N’Kaoua ◽  
Sandra Chanraud ◽  
...  
Keyword(s):  
Real Time ◽  
Cognitive Performance ◽  
Cognitive Functions ◽  
Positive Symptom ◽  
Psychotic Symptoms ◽  
Average Score ◽  
Symptom Expression ◽  
Causal Nature ◽  
Underlying Mechanisms ◽  
The Moment

AbstractDeficits in cognitive functions are frequent in schizophrenia and are often conceptualized as stable characteristics of this disorder. However, cognitive capacities may fluctuate over the course of a day and it is unknown if such variation may be linked to the dynamic expression of psychotic symptoms. This investigation used Ecological Momentary Assessment (EMA) to provide mobile tests of cognitive functions and positive symptoms in real time. Thirty-three individuals with schizophrenia completed five EMA assessments per day for a one-week period that included real-time assessments of cognitive performance and psychotic symptoms. A subsample of patients and 31 healthy controls also completed a functional MRI examination. Relative to each individual’s average score, moments of worsened cognitive performance on the mobile tests were associated with an increased probability of positive symptom occurrence over subsequent hours of the day (coef = 0.06, p < 0.05), adjusting for the presence of psychotic symptoms at the moment of mobile test administration. These prospective associations varied as a function of graph theory indices in MRI analyses. These findings demonstrate that cognitive performance is prospectively linked to psychotic symptom expression in daily life, and that underlying brain markers may be observed in the Executive Control Network. While the potential causal nature of this association remains to be investigated, our results offer promising prospects for a better understanding of the underlying mechanisms of symptom expression in schizophrenia.

Caffeine and Placebo Expectation

2007 ◽  
Vol 21 (2) ◽  
pp. 91-99 ◽  
Author(s):  
Yunfeng Sun ◽  
Yinling Zhang ◽  
Ning He ◽  
Xufeng Liu ◽  
Danmin Miao
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Sleep Deprivation ◽  
Cognitive Performance ◽  
Cognitive Functions ◽  
Cardiovascular Regulation ◽  
Double Blind ◽  
Positive Effects ◽  
Pressure Tests ◽  
Healthy Males

Abstract. Caffeine placebo expectation seems to improve vigilance and cognitive performance. This study investigated the effect of caffeine and placebo expectation on vigilance and cognitive performance during 28 h sleep deprivation. Ten healthy males volunteered to take part in the double-blind, cross-over study, which required participants to complete five treatment periods of 28 h separated by 1-week wash-out intervals. The treatments were no substance (Control); caffeine 200 mg at 00:00 (C200); placebo 200 mg at 00:00 (P200); twice caffeine 200 mg at 00:00 and 04:00 (C200-C200); caffeine 200 mg at 00:00 and placebo 200 mg at 04:00 (C200-P200). Participants were told that all capsules were caffeine and given information about the effects of caffeine to increase expectation. Vigilance was assessed by a three-letter cancellation test, cognitive functions by the continuous addition test and Stroop test, and cardiovascular regulation by heart rate and blood pressure. Tests were performed bihourly from 00:00 to 10:00 of the second day. Results indicated that C200-P200 and C200-C200 were more alert (p < .05) than Control and P200. Their cognitive functions were higher (p < .05) than Control and P200. Also, C200-P200 scored higher than C200 in the letter cancellation task (p < .05). No test showed any significant differences between C200-P200 and C200-C200. The results demonstrated that the combination of caffeine 200 mg and placebo 200 mg expectation exerted prolonged positive effects on vigilance and cognitive performance.

scholarly journals Caffeine and Cognitive Functions in Sports: A Systematic Review and Meta-Analysis

Nutrients ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 868
Author(s):  
Jorge Lorenzo Calvo ◽  
Xueyin Fei ◽  
Raúl Domínguez ◽  
Helios Pareja-Galeano
Keyword(s):  
Systematic Review ◽  
Reaction Time ◽  
Cognitive Performance ◽  
Cognitive Functions ◽  
Web Of Science ◽  
Meta Analysis ◽  
Caffeine Intake ◽  
Inclusion Criteria ◽  
Research Protocols ◽  
The Relationship

Cognitive functions are essential in any form of exercise. Recently, interest has mounted in addressing the relationship between caffeine intake and cognitive performance during sports practice. This review examines this relationship through a structured search of the databases Medline/PubMed and Web of Science for relevant articles published in English from August 1999 to March 2020. The study followed PRISMA guidelines. Inclusion criteria were defined according to the PICOS model. The identified records reported on randomized cross-over studies in which caffeine intake (as drinks, capsules, energy bars, or gum) was compared to an identical placebo situation. There were no filters on participants’ training level, gender, or age. For the systematic review, 13 studies examining the impacts of caffeine on objective measures of cognitive performance or self-reported cognitive performance were selected. Five of these studies were also subjected to meta-analysis. After pooling data in the meta-analysis, the significant impacts of caffeine only emerged on attention, accuracy, and speed. The results of the 13 studies, nevertheless, suggest that the intake of a low/moderate dose of caffeine before and/or during exercise can improve self-reported energy, mood, and cognitive functions, such as attention; it may also improve simple reaction time, choice reaction time, memory, or fatigue, however, this may depend on the research protocols.

scholarly journals Caffeine may disrupt the impact of real-time drowsiness on cognitive performance: a double-blind, placebo-controlled small-sample study

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
E. Aidman ◽  
M. Balin ◽  
K. Johnson ◽  
S. Jackson ◽  
G. M. Paech ◽  
...  
Keyword(s):  
Real Time ◽  
Cognitive Performance ◽  
Small Sample ◽  
Night Time ◽  
Double Blind ◽  
Infra Red ◽  
Procedural Decisions ◽  
Performance Gains ◽  
The Impact ◽  
Modest Reduction

AbstractCaffeine is widely used to promote alertness and cognitive performance under challenging conditions, such as sleep loss. Non-digestive modes of delivery typically reduce variability of its effect. In a placebo-controlled, 50-h total sleep deprivation (TSD) protocol we administered four 200 mg doses of caffeine-infused chewing-gum during night-time circadian trough and monitored participants' drowsiness during task performance with infra-red oculography. In addition to the expected reduction of sleepiness, caffeine was found to disrupt its degrading impact on performance errors in tasks ranging from standard cognitive tests to simulated driving. Real-time drowsiness data showed that caffeine produced only a modest reduction in sleepiness (compared to our placebo group) but substantial performance gains in vigilance and procedural decisions, that were largely independent of the actual alertness dynamics achieved. The magnitude of this disrupting effect was greater for more complex cognitive tasks.

The Unbearable Lightness of the Image

2017 ◽  
Vol 10 (2-3) ◽  
pp. 109-132 ◽  
Author(s):  
Donatella Della Ratta
Keyword(s):  
Web 2.0 ◽  
Real Time ◽  
New Technologies ◽  
Political Commitment ◽  
Life Activity ◽  
Bearing Witness ◽  
Ethical Discourse ◽  
The Aesthetic ◽  
The Moment ◽  
The Web

In this essay, I reflect on the aesthetic, political and material implications of filming as a continuous life activity since the beginning of the 2011 uprising in Syria. I argue that the blurry, shaky and pixelated aesthetics of Syrian user-generated videos serve to construct an ethical discourse (Ranciére 2009a; 2013) to address the genesis and the goal of the images produced, and to shape a political commitment to the evidence-image (Didi-Huberman 2008). However, while the unstable visuals of the handheld camera powerfully reconnect, both at a symbolic and aesthetic level, to the truthfulness of the moment of crisis in which they are generated, they fail to produce a clearer understanding of the situation and a counter-hegemonic narrative. In this article, I explore how new technologies have impacted this process of bearing witness and documenting events in real time, and how they have shaped a new understanding of the image as a networked, multiple object connected with the living archive of history, in a permanent dialogue with the seemingly endless flow of data nurtured by the web 2.0.

scholarly journals Cell-Based Regeneration and Treatment of Liver Diseases

2021 ◽  
Vol 22 (19) ◽  
pp. 10276
Author(s):  
Julia Hofmann ◽  
Verena Hackl ◽  
Hannah Esser ◽  
Andras T. Meszaros ◽  
Margot Fodor ◽  
...  
Keyword(s):  
Liver Diseases ◽  
Ex Vivo ◽  
Organ Shortage ◽  
Clinical Implementation ◽  
Organ Function ◽  
Novel Technologies ◽  
Recent Developments ◽  
Underlying Mechanisms ◽  
The Moment ◽  
End Stage

The liver, in combination with a functional biliary system, is responsible for maintaining a great number of vital body functions. However, acute and chronic liver diseases may lead to irreversible liver damage and, ultimately, liver failure. At the moment, the best curative option for patients suffering from end-stage liver disease is liver transplantation. However, the number of donor livers required by far surpasses the supply, leading to a significant organ shortage. Cellular therapies play an increasing role in the restoration of organ function and can be integrated into organ transplantation protocols. Different types and sources of stem cells are considered for this purpose, but highly specific immune cells are also the focus of attention when developing individualized therapies. In-depth knowledge of the underlying mechanisms governing cell differentiation and engraftment is crucial for clinical implementation. Additionally, novel technologies such as ex vivo machine perfusion and recent developments in tissue engineering may hold promising potential for the implementation of cell-based therapies to restore proper organ function.

scholarly journals Experience as cognition: musical sense-making and the ‘in-time/ outside-of-time’ dichotomy

2019 ◽  
pp. 53-80 ◽  
Author(s):  
Mark Reybrouck
Keyword(s):  
Real Time ◽  
Continuous Flow ◽  
Sense Making ◽  
Levels Of Processing ◽  
Symbolic Processing ◽  
Sensory Reactivity ◽  
History Of ◽  
The Moment ◽  
High Level ◽  
Comprehensive Framework

Musical sense-making relies on two distinctive strategies: tracking the moment-to-moment history of the actual unfolding and recollecting actual and previous sounding events in a kind of synoptic overview. Both positions are not opposed but complement each other. The aim of this contribution, therefore, is to provide a comprehensive framework that provides both conceptual and operational tools for coping with the sounds. Five major possibilities are proposed in this regard: (i) the concepts of perspective and resolution, which refer to the distance the listener takes with respect to the sounding music and the fine-grainedness of his/her discriminative abilities; (ii) the continuous/discrete dichotomy which conceives of the music as one continuous flow as against a division in separate and distinct elements; (iii) the in time/outside-of-time distinction, with the former proceeding in real time and the latter proceeding outside of the time of unfolding; (iv) the deictic approach to musical sense-making, which conceives of an act of mental pointing to the music, and (v) the levels of processing, which span a continuum between primitive sensory reactivity to actual sounding stimuli and high-level symbolic processing.

scholarly journals Using Digital Twining in Fast-food Production Chain Simulation

2021 ◽  
Vol 343 ◽  
pp. 03005
Author(s):  
Florina Chiscop ◽  
Bogdan Necula ◽  
Carmen Cristiana Cazacu ◽  
Cristian Eugen Stoica
Keyword(s):  
Real Time ◽  
Fast Food ◽  
Virtual Model ◽  
Time Data ◽  
Production Chain ◽  
The Real ◽  
Time Dynamic ◽  
Digital Twin ◽  
Food Company ◽  
The Moment

The topic of this paper represents our research in the process of creating a virtual model (digital twin) for a fast-food company production chain starting with the moment when a customer launches an order, following with the processing of that order, until the customer receives it. The model will describe elements that are included in this process such as equipment, human resources and the necessary space that is needed to host this layout. The virtual model created in a simulation platform will be a replicate of a real fast-food company, thus helping us observe the real time dynamic of this production system. Using WITNESS HORIZON 23 we will construct the model of the layout based on real time data received from the fast-food company. This digital twin will be used to manage the production chain material flow, evaluating the performance of the system architecture in various scenarios. In order to obtain a diagnosis of the system’s performance we will simulate the workflow running through preliminary architecture in compliance with the real time behaviour to identify the bottlenecks and blockages in the flow trajectory. In the end we will propose two different optimised architectures for the fast-food company production chain.

Aberrant Salience among Young Healthy Postgraduate University Students: The Role of Cannabis Use, Psychotic-Like Experiences, and Personality

2022 ◽  
pp. 1-7
Author(s):  
Andrea Patti ◽  
Gabriele Santarelli ◽  
Giulio D’Anna ◽  
Andrea Ballerini ◽  
Valdo Ricca
Keyword(s):  
University Students ◽  
Personality Traits ◽  
Cannabis Use ◽  
Positive Symptom ◽  
Psychotic Symptoms ◽  
Symptom Frequency ◽  
Character Inventory ◽  
Aberrant Salience ◽  
Self Transcendence

Aberrant salience (AS) is an anomalous world experience which plays a major role in psychotic proneness. In the general population, a deployment of this construct – encompassing personality traits, psychotic-like symptoms, and cannabis use – could prove useful to outline the relative importance of these factors. For this purpose, 106 postgraduate university students filled the AS Inventory (ASI), the Community Assessment of Psychic Experiences (CAPE), the Temperament and Character Inventory (TCI), and the Symptom Checklist 90-Revised (SCL-90-R). Lifetime cannabis users (<i>n</i> = 56) and individuals who did not use cannabis (<i>n</i> = 50) were compared. The role of cannabis use and psychometric indexes on ASI total scores was tested in different subgroups (overall sample, cannabis users, and nonusers). The present study confirmed that cannabis users presented higher ASI scores. The deployment of AS proved to involve positive symptom frequency (assessed through CAPE), character dimensions of self-directedness and self-transcendence (TCI subscales), and cannabis use. Among nonusers, the role of personality traits (assessed through the TCI) was preeminent, whereas positive psychotic-like experiences (measured by means of CAPE) had a major weight among cannabis users. The present study suggests that pre-reflexive anomalous world experiences such as AS are intertwined with reflexive self-consciousness, personality traits, current subclinical psychotic symptoms, and cannabis use. In the present study, subthreshold psychotic experiences proved to play a major role among cannabis users, whereas personality appeared to be more relevant among nonusers.

Neural substrate and underlying mechanisms of working memory: insights from brain stimulation studies

2021 ◽  
Author(s):  
Zakia Z Haque ◽  
Ranshikha Samandra ◽  
Farshad Alizadeh Mansouri
Keyword(s):  
Working Memory ◽  
Brain Stimulation ◽  
Cognitive Functions ◽  
Cognitive Abilities ◽  
Relevant Information ◽  
Brain Regions ◽  
Electrophysiological Recording ◽  
Great Opportunity ◽  
Neural Substrate ◽  
Underlying Mechanisms

The concept of working memory refers to a collection of cognitive abilities and processes involved in the short-term storage of task-relevant information to guide the ongoing and upcoming behaviour and therefore describes an important aspect of executive control of behaviour for achieving goals. Deficits in working memory and related cognitive abilities have been observed in patients with brain damage or neuropsychological disorders and therefore it is important to better understand neural substrate and underlying mechanisms of working memory. Working memory relies on neural mechanisms that enable encoding, maintenance and manipulation of stored information as well as integrating them with ongoing and future goals. Recently, a surge in brain stimulation studies have led to development of various non-invasive techniques for localized stimulation of prefrontal and other cortical regions in humans. These brain stimulation techniques can potentially be tailored to influence neural activities in particular brain regions and modulate cognitive functions and behaviour. Combined use of brain stimulation with neuroimaging and electrophysiological recording have provided a great opportunity to monitor neural activity in various brain regions and non-invasively intervene and modulate cognitive functions in cognitive tasks. These studies have shed more light on the neural substrate and underlying mechanisms of working memory in humans. Here, we review findings and insight from these brain stimulation studies about the contribution of brain regions, and particularly prefrontal cortex, to working memory.

scholarly journals Single-molecule imaging reveals control of parental histone recycling by free histones during DNA replication

2020 ◽  
Vol 6 (38) ◽  
pp. eabc0330 ◽  
Author(s):  
D. T. Gruszka ◽  
S. Xie ◽  
H. Kimura ◽  
H. Yardimci
Keyword(s):  
Dna Replication ◽  
Real Time ◽  
Single Molecule ◽  
Replication Fork ◽  
Epigenetic Inheritance ◽  
Replication Forks ◽  
Replication Fork Progression ◽  
Egg Extracts ◽  
Fork Stalling ◽  
The Moment

During replication, nucleosomes are disrupted ahead of the replication fork, followed by their reassembly on daughter strands from the pool of recycled parental and new histones. However, because no previous studies have managed to capture the moment that replication forks encounter nucleosomes, the mechanism of recycling has remained unclear. Here, through real-time single-molecule visualization of replication fork progression in Xenopus egg extracts, we determine explicitly the outcome of fork collisions with nucleosomes. Most of the parental histones are evicted from the DNA, with histone recycling, nucleosome sliding, and replication fork stalling also occurring but at lower frequencies. Critically, we find that local histone recycling becomes dominant upon depletion of endogenous histones from extracts, revealing that free histone concentration is a key modulator of parental histone dynamics at the replication fork. The mechanistic details revealed by these studies have major implications for our understanding of epigenetic inheritance.

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