Neurocognitive State Research Articles

Macroscale brain states support the control of semantic cognition

A crucial aim in neuroscience is to understand how the human brain adapts to varying cognitive demands. This study investigates network reconfiguration during controlled semantic retrieval in differing contexts. We analyze brain responses to two semantic tasks of varying difficulty – global association and feature matching judgments – which are contrasted with non-semantic tasks on the cortical surface and within a whole-brain state space. Demanding semantic association tasks elicit activation in anterior prefrontal and temporal regions, while challenging semantic feature matching and non-semantic tasks predominantly activate posterior regions. Task difficulty also modulates activation along different dimensions of functional organization, suggesting different mechanisms of cognitive control. More demanding semantic association judgments engage cognitive control and default mode networks together, while feature matching and non-semantic tasks are skewed towards cognitive control networks. These findings highlight the brain’s dynamic ability to tailor its networks to support diverse neurocognitive states, enriching our understanding of controlled cognition.

Individualized Tracking of Neurocognitive-State-Dependent Eye-Movement Features Using Mobile Devices

With current clinical techniques, it is difficult to assess a patient's neurodegenerative disease (e.g., Alzheimer's) state accurately and frequently. The most widely used tests are qualitative or only performed intermittently, motivating the need for quantitative, accurate, and unobtrusive metrics to track disease progression. Clinical studies have shown that saccade latency (an eye movement measure of reaction time) and error rate (the proportion of eye movements in the wrong direction) may be significantly affected by neurocognitive diseases. Nevertheless, how these features change over time as a disease progresses is underdeveloped due to the constrained recording setup. In this work, our goal is to first understand how these features change over time in healthy individuals. To do so, we used a mobile app to frequently and accurately measure these features outside of the clinical environment from 80 healthy participants. We analyzed their longitudinal characteristics and designed an individualized longitudinal model using a Gaussian process. With a system that can measure eye-movement features on a much finer timescale in a broader population, we acquired a better understanding of eye-movement features from healthy individuals and provided research directions in understanding whether eye-movement features can be used to track neurocognitive states.

Factors related to employment in childhood cancer survivors in Japan: A preliminary study.

Previous research has revealed vocational and academic difficulties in childhood cancer survivors, and explored impact of survivors' medical history and physical function on vocational and academic status. However, we often encounter survivors with similar diagnoses and late effects but different academic or employment statuses. This raises the question of what affects academic attainment and employment other than treatment or late effects. This study aimed to explore factors associated with childhood cancer survivors' employment status and academic achievement. Comprehensive health check-up and questionnaire survey were conducted for 69 survivors who were over the age of 18 and participated in St. Luke's Lifetime cohort study. We obtained survivors' biological function using comprehensive health check-up, neurocognitive states, quality of life, transition readiness, and family function. We conducted univariate analysis (Mann-Whitney U tests or chi-square tests) to compare the differences between the regular workers/students and non-regular workers/unemployed groups. The variables with p-values <0.1 were used as independent variables multivariate logistic regression to explore predictors of employment status and academic attainment. Result of the univariate analysis, intelligence quotient, SF-8 PCS, transition readiness, family function were used for multivariate logistic regression as independent variables. The stepwise likelihood method was conducted; intelligence quotient (odds ratio [OR] = 1.100; 95% confidence interval [CI] 1.015-1.193; p = 0.021), transition readiness (OR = 0.612; 95% CI 0.396-0.974; p = 0.038), and family function (OR = 2.337; 95% CI 1.175-4.645; p = 0.015) were found to be associated with survivors' regular workers/students in the final regression model. Long-term follow-up of pediatric cancer survivors requires the provision of total care, which supports physical, psychological, and social functions to improve health, readiness for transition to self-management, and family functioning.

Anticipatory attention is a stable state induced by transient control mechanisms.

Anticipatory attention is a neurocognitive state in which attention control regions bias neural activity in sensory cortical areas to facilitate the selective processing of incoming targets. Previous electroencephalographic (EEG) studies have identified event-related potential (ERP) signatures of anticipatory attention, and implicated alpha band (8–12 Hz) EEG oscillatory activity in the selective control of neural excitability in visual cortex. However, the degree to which ERP and alpha band measures reflect related or distinct underlying neural processes remains to be further understood. To investigate this question, we analyzed EEG data from 20 human participants performing a cued object-based attention task. We used support vector machine (SVM) decoding analysis to compare the attentional time courses of ERP signals and alpha band power. We found that ERP signals encoding attentional instructions are dynamic and precede stable attention-related changes in alpha power, suggesting that ERP and alpha power reflect distinct neural processes. We proposed that the ERP patterns reflect transient attentional orienting signals originating in higher order control areas, whereas the patterns of synchronized oscillatory neural activity in the alpha band reflect a sustained attentional state. These findings support the hypothesis that anticipatory attention involves transient top-down control signals that establish more stable neural states in visual cortex, enabling selective sensory processing.

Varied Composition and Underlying Mechanisms of Gut Microbiome in Neuroinflammation.

The human gut microbiome has been implicated in a host of bodily functions and their regulation, including brain development and cognition. Neuroinflammation is a relatively newer piece of the puzzle and is implicated in the pathogenesis of many neurological disorders. The microbiome of the gut may alter the inflammatory signaling inside the brain through the secretion of short-chain fatty acids, controlling the availability of amino acid tryptophan and altering vagal activation. Studies in Korea and elsewhere highlight a strong link between microbiome dynamics and neurocognitive states, including personality. For these reasons, re-establishing microbial flora of the gut looks critical for keeping neuroinflammation from putting the whole system aflame through probiotics and allotransplantation of the fecal microbiome. However, the numerosity of the microbiome remains a challenge. For this purpose, it is suggested that wherever possible, a fecal microbial auto-transplant may prove more effective. This review summarizes the current knowledge about the role of the microbiome in neuroinflammation and the various mechanism involved in this process. As an example, we have also discussed the autism spectrum disorder and the implication of neuroinflammation and microbiome in its pathogenesis.

Combined treatment with Ginkgo biloba extract EGb 761 plus acetylcholinesterase inhibitors improved cognitive function and neuropsychiatric symptoms in patients with mild cognitive impairment.

IntroductionMild cognitive impairment (MCI) is a neurocognitive state between normal aging and dementia. There is currently no approved treatment for MCI, with acetylcholinesterase inhibitors (AChEI) being the commonly prescribed drugs. The Ginkgo biloba extract EGb 761 is an herbal remedy used for cognitive disorders, including dementia. This study aims to explore the potential synergistic effect of combination therapy with EGb 761 plus AChEI in patients with amnestic MCI in a real‐life setting.MethodsWe retrospectively identified 133 patients with amnestic MCI who were attending a memory clinic. Patients had received treatment with any of the following drugs: G. biloba extract EGb 761, donepezil, galantamine, or rivastigmine at their standard doses. Subjects were divided into three treatment groups: EGb 761, AChEI, and EGb 761+AChEI. Patients were assessed by Mini‐Mental State Examination (MMSE), Rey Auditory Verbal Learning Test (RAVLT), Symbol Digit Modalities Test, Boston Naming Test, Trail Making Test (TMT Parts A and B), Letter and Category Fluency Test (LFT, CFT), Neuropsychiatric Inventory (NPI), and Interview for Deterioration in Daily Living. Mixed‐effects model analysis was carried out to evaluate changes in cognitive, functional, and behavioral outcomes over a 12‐month follow‐up.ResultsAfter 12 months, EGb 761+AChEI showed significant improvement in MMSE, RAVLT, CFT, TMT A‐B, and NPI compared to AChEI and in MMSE and RAVLT compared to EGb 761. At 12 months, EGb 761 was superior to AChEI on the CFT, TMT A‐B, and NPI.DiscussionOur findings suggest that combined therapy with EGb 761 plus AChEI may provide added cognitive and functional benefits in patients with MCI and provides additional real‐world evidence for the combined use of EGb 761 and anti‐dementia drugs in patients with MCI. This study can serve as a model for the design of clinical trials that help to support the combined use of EGb 761 and anti‐dementia drugs in patients with MCI.

Neurocognitive state and quality of life of patients with glioblastoma in Mediterranean countries: a systematic review.

Gliomas are the most common primary tumors of the central nervous system (CNS). The most common subtype of glioma in adults is grade IV astrocytoma, known as glioblastoma (GB) multiforme. Despite advances in treatment, GB remains a lethal tumor with a poor prognosis, and patients face serious quality of life (QoL) issues. Its poor prognosis is a real public health problem. The present study aimed to determine the exact neurocognitive status and QoL in patients with GB in the Mediterranean region and the different predictive factors responsible for their deterioration. This systematic review was conducted in accordance with PRISMA guidelines. The protocol was registered in the PROSPERO (Identifier: CRD42020188936). The following databases have been independently searched by 2 authors: PubMed, Science Direct, Scopus and Google Scholar. Thirteen studies were selected (n=13). Four studies (n=4) focused solely on cognitive assessment, five studies (n=5) focused on quality-of-life assessment, and four (n=4) were simultaneously assessed QoL and neurocognitive status. The majority of studies in this review use (Mini-Mental State Examination, MMSE) for an overall cognitive assessment (n=5), other studies use specific batteries for an in-depth assessment of cognitive functions (n=3). The study revealed several affected functions: short and long-term memory, executive functions (EFs), and visuo-constructive abilities. Scale of European Organization for Research and Treatment of Cancer and the Functional Assessment of Cancer Therapy are among the most widely used instruments for assessing QoL. For factors influencing neurocognitive status and QoL, the present review found that: The Karnofsky Performance Scale (KPS), tumor location, age, sex and type of treatment are the most identified. Other studies have reported other factors, such as tumor progression, development of emotional distress, and coping strategies adopted. We conclude that there were many changes in patients with GB during the course of the disease and that most of them were related to age and disease progression. The use of coping strategies based on social support has a positive impact on the QoL.

Metabolic, Affective and Neurocognitive Characterization of Metabolic Syndrome Patients with and without Food Addiction. Implications for Weight Progression.

According to the food addiction (FA) model, the consumption of certain types of food could be potentially addictive and can lead to changes in intake regulation. We aimed to describe metabolic parameters, dietary characteristics, and affective and neurocognitive vulnerabilities of individuals with and without FA, and to explore its influences on weight loss progression. The sample included 448 adults (55–75 years) with overweight/obesity and metabolic syndrome from the PREDIMED-Plus cognition sub-study. Cognitive and psychopathological assessments, as well as dietary, biochemical, and metabolic measurements, were assessed at baseline. Weight progression was evaluated after a 3-year follow up. The presence of FA was associated with higher depressive symptomatology, neurocognitive decline, low quality of life, high body mass index (BMI), and high waist circumference, but not with metabolic comorbidities. No differences were observed in the dietary characteristics except for the saturated and monounsaturated fatty acids consumption. After three years, the presence of FA at baseline resulted in a significantly higher weight regain. FA is associated with worse psychological and neurocognitive state and higher weight regain in adults with metabolic syndrome. This condition could be an indicator of bad prognosis in the search for a successful weight loss process.

The why behind the high: determinants of neurocognition during acute cannabis exposure.

Acute cannabis intoxication may induce neurocognitive impairment and is a possible cause of human error, injury and psychological distress. One of the major concerns raised about increasing cannabis legalization and the therapeutic use of cannabis is that it will increase cannabis-related harm. However, the impairing effect of cannabis during intoxication varies among individuals and may not occur in all users. There is evidence that the neurocognitive response to acute cannabis exposure is driven by changes in the activity of the mesocorticolimbic and salience networks, can be exacerbated or mitigated by biological and pharmacological factors, varies with product formulations and frequency of use and can differ between recreational and therapeutic use. It is argued that these determinants of the cannabis-induced neurocognitive state should be taken into account when defining and evaluating levels of cannabis impairment in the legal arena, when prescribing cannabis in therapeutic settings and when informing society about the safe and responsible use of cannabis.

An Analysis of the External Validity of EEG Spectral Power in an Uncontrolled Outdoor Environment during Default and Complex Neurocognitive States.

Traditionally, quantitative electroencephalography (QEEG) studies collect data within controlled laboratory environments that limit the external validity of scientific conclusions. To probe these validity limits, we used a mobile EEG system to record electrophysiological signals from human participants while they were located within a controlled laboratory environment and an uncontrolled outdoor environment exhibiting several moderate background influences. Participants performed two tasks during these recordings, one engaging brain activity related to several complex cognitive functions (number sense, attention, memory, executive function) and the other engaging two default brain states. We computed EEG spectral power over three frequency bands (theta: 4–7 Hz, alpha: 8–13 Hz, low beta: 14–20 Hz) where EEG oscillatory activity is known to correlate with the neurocognitive states engaged by these tasks. Null hypothesis significance testing yielded significant EEG power effects typical of the neurocognitive states engaged by each task, but only a beta-band power difference between the two background recording environments during the default brain state. Bayesian analysis showed that the remaining environment null effects were unlikely to reflect measurement insensitivities. This overall pattern of results supports the external validity of laboratory EEG power findings for complex and default neurocognitive states engaged within moderately uncontrolled environments.

&lt;i&gt;Shank3&lt;/i&gt; Mutations Impair Electrical Synapse Scaffolding and Transmission in Mouse Brain

Shank3 mutations contribute to intellectual disability. Because SHANK3 is a protein scaffold that helps organize the multiprotein network of the glutamatergic postsynaptic density (PSD), alterations in chemical synaptic transmission are implicated. Electrical synaptic transmission is a second form of synaptic transmission, enabled by intercellular channels comprised of connexin36 that support direct electrical communication among neurons, electrical brain rhythms, and neurocognitive states. Using multiplex proteomics, we report that two autism-related mutations of mouse Shank3 disrupt the glutamatergic PSD differently, but have in common the disruption of an association between NMDA-type glutamate-receptors (NMDARs) and connexin36. Mutation of Shank3 exons 13-16 most robustly dissociated connexin36 from NMDARs while impairing electrical synaptic transmission and the synchrony of an electrical rhythm in mouse inferior olive. We suggest that electrical synapses are a component of an “extended PSD” sensitive to Shank3 mutations that produce intellectual disability, at least in part, by impairing electrical synaptic transmission.

Frontoparietal action-oriented codes support novel instruction implementation

A key aspect of human cognitive flexibility concerns the ability to convert complex symbolic instructions into novel behaviors. Previous research proposes that this transformation is supported by two neurocognitive states: an initial declarative maintenance of task knowledge, and an implementation state necessary for optimal task execution. Furthermore, current models predict a crucial role of frontal and parietal brain regions in this process. However, whether declarative and procedural signals independently contribute to implementation remains unknown. We report the results of an fMRI experiment in which participants executed novel instructed stimulus-response associations. We then used a pattern-tracking procedure to quantify the contribution of format-unique signals during instruction implementation. This revealed independent procedural and declarative representations of novel S-Rs in frontoparietal areas, prior to execution. Critically, the degree of procedural activation predicted subsequent behavioral performance. Altogether, our results suggest an important contribution of frontoparietal regions to the neural architecture that regulates cognitive flexibility.

Reductions in task positive neural systems occur with the passage of time and are associated with changes in ongoing thought

Cognition is dynamic and involves both the maintenance of and transitions between neurocognitive states. While recent research has identified some of the neural systems involved in sustaining task states, it is less well understood how intrinsic influences on cognition emerge over time. The current study uses fMRI and Multi-Dimensional Experience Sampling (MDES) to chart how cognition changes over time from moments in time when external attention was established. We found that the passage of time was associated with brain regions associated with external attention decreasing in activity over time. Comparing this pattern of activity to defined functional hierarchies of brain organization, we found that it could be best understood as movement away from systems involved in task performance. Moments where the participants described their thoughts as off-task showed a significant similarity to the task-negative end of the same hierarchy. Finally, the greater the similarity of a participant’s neural dynamics to this hierarchy the faster their rate of increasing off-task thought over time. These findings suggest topographical changes in neural processing that emerge over time and those seen during off-task thought can both be understood as a common shift away from neural motifs seen during complex task performance.

A Neuroergonomics Approach to Mental Workload, Engagement and Human Performance.

The assessment and prediction of cognitive performance is a key issue for any discipline concerned with human operators in the context of safety-critical behavior. Most of the research has focused on the measurement of mental workload but this construct remains difficult to operationalize despite decades of research on the topic. Recent advances in Neuroergonomics have expanded our understanding of neurocognitive processes across different operational domains. We provide a framework to disentangle those neural mechanisms that underpin the relationship between task demand, arousal, mental workload and human performance. This approach advocates targeting those specific mental states that precede a reduction of performance efficacy. A number of undesirable neurocognitive states (mind wandering, effort withdrawal, perseveration, inattentional phenomena) are identified and mapped within a two-dimensional conceptual space encompassing task engagement and arousal. We argue that monitoring the prefrontal cortex and its deactivation can index a generic shift from a nominal operational state to an impaired one where performance is likely to degrade. Neurophysiological, physiological and behavioral markers that specifically account for these states are identified. We then propose a typology of neuroadaptive countermeasures to mitigate these undesirable mental states.

Dynamic internal states shape memory retrieval

Why do we sometimes easily retrieve memories, but other times appear to forget them? We often look to our external environment for retrieval cues, but another way to optimize memory retrieval is to be in a mental state, or mode, that prioritizes access to our internal representation of the world. Such a ‘retrieval mode’ was proposed by Endel Tulving (1983), who considered it a neurocognitive state in which one keeps the goal of memory retrieval in mind. Building on Tulving's proposal, we review converging evidence from multiple lines of research that emphasize the importance of internal states in the instantiation of retrieval modes that optimize successful remembering. We identify three key factors that contribute to a retrieval mode by modulating either the likelihood or the content of retrieval: (1) an intention to remember or forget (either in the present or the future), (2) attentional selection of goal-relevant memories and suppression of distractors, and (3) fluctuating levels of acetylcholine in the hippocampus. We discuss empirical evidence that these internal states individually influence memory retrieval and propose how they may interact synergistically. Characterizing these dynamic internal factors is an important key for unlocking our understanding of the organization and accessibility of our memories.

Evaluation of oxidative stress, blood parameters, and neurocognitive status in cement factory workers

The current investigation was aimed to evaluate the oxidative stress (OS), blood factors, and neurocognitive state among cement factory workers who are exposed to dust during their work. Totally 41 cement exposed workers and 41 subjects as a control group were selected, and their OS, biochemical parameters, and a neurocognitive questionnaire were assessed. The results indicated that the levels of triglyceride, alanine aminotransferase, and alkaline phosphatase were higher among the exposed workers. The rate of lipid peroxidation and total antioxidant capacity were not significantly differenced among the workers while compared to the control group. Highlights Cement industry may lead to several health impairments among cement workers. A significant association between past dust exposure in the workplace and neurocognitive impairment. Occupational exposures to these dusts may result later in life in adverse mental health outcomes.

Identification and Management of Ischemic Stroke in the Postanesthesia Care Unit

A thromboembolic stroke is a debilitating event that can occur with little or no warning. This report details the case of a 63-year-old male experiencing a stroke in the immediate postoperative period after total knee arthroplasty. Risk for perioperative stroke is influenced by age, sex, ethnicity, comorbidities, and some medications. The depressed neurocognitive state of patients recovering from anesthesia warrants special consideration for the identification and management of perioperative stroke.

Learned Helplessness After Anterior Cruciate Ligament Reconstruction: An Altered Neurocognitive State?

Traumatic knee injuries, such as anterior cruciate ligament (ACL) sprains, have detrimental effects on long-term health as they initiate a cycle of chronic pain, physical inactivity, and disability. Alterations in strength and neural activity are factors that contribute to rehabilitation failure after ACL reconstruction (ACLR); however, psychological deficits also hinder rehabilitative success. Neural impairments observed following injury and ACLR may be associated with psychological dysfunction, a phenomenon defined as learned helplessness (LH). The proposed framework establishes the link between depressed neural activity and psychological dysfunction after ACL injury using foundational evidence from neuroscience and psychology to support the integration of LH into recovery.

Neurocognitive profile of patients with early stages of HIV infection

HIV-associated neurocognitive disorders (HAND) may include neurological disorders of various severities such as AIDS dementia complex (ADC) also known as HIV dementia and HIV-associated dementia (HAD), HIV encephalopathy, and Mild Neurocognitive Disorder (MND). As it seems HIV-associated neurocognitive disorders are associated with a metabolic encephalopathy induced by HIV infection and fueled by immune activation of macrophages and microglia. Despite of a group, evidences have described presence of cognitive alterations in HIV patients at different stages of HIV infection so far; little is known about the neurocognitive state of patients at very early stages of HIV infection. Here, we explored the neurocognitive profile of a group of cases of HIV patients at very early stages of HIV infection. We have analyzed of three groups of subjects, thus, we have studied a group of patients with early HIV infection, a healthy control group and a group of patients with mild cognitive impairment due to neurodegenerative causes. Our results suggested that cognitive processes are sensitive to very early neuropathological changes in HIV infection. Noteworthy, our results also showed that neurocognitive profile of HIV patients differs from those cognitive alterations in patients with mild cognitive disorders associated to primary neurodegeneration. Together, our results point out that HIV infection generates neural changes even at early stages of infection. Furthermore, our results highlight the importance of a deep neurocognitive exploration at very early stages of HIV infection as this approach allow improve the accompaniment, clinical attachment and interventions.Disclosure of interestThe authors have not supplied their declaration of competing interest.

Effectiveness study of “occupational connections” – A short-term, in-patient intervention for promotion functioning and participation in daily life of people with mental health conditions

ObjectivesMental health conditions (MHC) have been associated with restrictions in daily life participation and functioning affecting health and well-being. Substantial numbers of people with MHC experience hospitalizations, however, there is limited evidence supporting functional interventions in the in-patient setting to promote recovery. The OC is an intervention implemented during sub-acute hospitalization, which attempts to promote activity and participation of people with MHC, both during the in-patient stay and upon return to the community, with a view to enabling recovery. To facilitate its implementation, we investigate the OC effectiveness.AimsInvestigate the OC contribution to cognition, symptoms and functional capacity among inpatients with schizophrenia.MethodsThis is a quasi-experimental, prospective, pre/post-designed study with convenience sampling. Inpatients with schizophrenia were enrolled into the study group participating in the OC intervention (n = 16); or the control group participating in hospital treatment as usual (n = 17). The study participants completed evaluations at baseline and at discharge or after 10 weeks with: Neurocognitive State Examination, Trail Making Test, Ray Complex Figure, and Category Fluency Test for aspects of cognition; Positive and Negative Syndrome Scale for symptoms severity, and Observed Tasks of Daily Living-Revised for functional capacity.ResultsStatistically significant improvement in cognitive functioning, symptoms severity and functional capacity was found in the study group after the intervention. These changes were not observed in the control group.ConclusionThe results support the OC effectiveness for cognitive and functional capacity improvement and symptomology relief. The findings advance the body of evidence for functional interventions in hospital settings.Disclosure of interestThe authors have not supplied their declaration of competing interest.