rudyvdbrink/CitationDatabase huggingface dataset:
The role of herpesvirus 6A and 6B in multiple sclerosis and epilepsy.
Scandinavian journal of immunology, 2020

Human herpesvirus 6A (HHV-6A) and 6B (HHV-6B) are two closely related viruses that can infect cells of the central nervous system (CNS). The similarities between these viruses have made it difficult to separate them on serological level. The broad term HHV-6 remains when referring to studies where the two species were not distinguished, and as such, the seroprevalence is over 90% in the adult population. HHV-6B has been detected in up to 100% of infants with the primary infection roseola infantum, but less is known about the primary infection of HHV-6A. Both viruses are neurotropic and have capacity to establish lifelong latency in cells of the central nervous system, with potential to reactivate and cause complications later in life. HHV-6A infection has been associated with an increased risk of multiple sclerosis (MS), whereas HHV-6B is indicated to be involved in pathogenesis of epilepsy. These two associations show how neurological diseases might be caused by viral infections, but as suggested here, through completely different molecular mechanisms, in an autoimmune disease, such as MS, by triggering an overreaction of the immune system and in epilepsy by hampering internal cellular functions when the immune system fails to eliminate the virus. Understanding the viral mechanisms of primary infection and reactivation and their spectrum of associated symptoms will aid our ability to diagnose, treat and prevent these severe and chronic diseases. This review explores the role of HHV-6A and HHV-6B specifically in MS and epilepsy, the evidence to date and the future directions of this field.
Demographically adjusted trail making test norms in a Scandinavian sample from 41 to 84 years.
The Clinical neuropsychologist, 2020

The trail making test (TMT) is one of the most widely used neuropsychological tests. TMT-A provides measures of visual scanning/visuomotor speed and TMT-B involves additional demands on executive functions. Derived scores TMT B-A and TMT B/A enhance measures of executive functioning. However, simple B-A subtraction may lead to false estimates of executive dysfunction in clinical samples. Norms for TMT have been published in several countries but are currently lacking for Scandinavia.
Serial dependence promotes the stability of perceived emotional expression depending on face similarity.
Attention, perception & psychophysics, 2018

Individuals can quickly and effortlessly recognize facial expressions, which is critical for social perception and emotion regulation. This sensitivity to even slight facial changes could result in unstable percepts of an individual's expression over time. The visual system must therefore balance accuracy with maintaining perceptual stability. However, previous research has focused on our sensitivity to changing expressions, and the mechanism behind expression stability remains an open question. Recent results demonstrate that perception of facial identity is systematically biased toward recently seen visual input. This positive perceptual pull, or serial dependence, may help stabilize perceived expression. To test this, observers judged random facial expression morphs ranging from happy to sad to angry. We found a pull in perceived expression toward previously seen expressions, but only when the 1-back and current face had similar identities. Our results are consistent with the existence of the continuity field for expression, a specialized mechanism that promotes the stability of emotion perception, which could help facilitate social interactions and emotion regulation.
Non-equilibrium landscape and flux reveal the stability-flexibility-energy tradeoff in working memory.
PLoS computational biology, 2020

Uncovering the underlying biophysical principles of emergent collective computational abilities, such as working memory, in neural circuits is one of the most essential concerns in modern neuroscience. Working memory system is often desired to be robust against noises. Such systems can be highly flexible for adapting environmental demands. How neural circuits reconfigure themselves according to the cognitive task requirement remains unclear. Previous studies explored the robustness and the flexibility in working memory by tracing individual dynamical trajectories in a limited time scale, where the accuracy of the results depends on the volume of the collected statistical data. Inspired by thermodynamics and statistical mechanics in physical systems, we developed a non-equilibrium landscape and flux framework for studying the neural network dynamics. Applying this approach to a biophysically based working memory model, we investigated how changes in the recurrent excitation mediated by slow NMDA receptors within a selective population and mutual inhibition mediated by GABAergic interneurons between populations affect the robustness against noises. This is realized through quantifying the underlying non-equilibrium potential landscape topography and the kinetics of state switching. We found that an optimal compromise for a working memory circuit between the robustness and the flexibility can be achieved through the emergence of an intermediate state between the working memory states. An optimal combination of both increased self-excitation and inhibition can enhance the flexibility to external signals without significantly reducing the robustness to the random fluctuations. Furthermore, we found that the enhanced performance in working memory is supported by larger energy consumption. Our approach can facilitate the design of new network structure for cognitive functions with the optimal balance between performance and cost. Our work also provides a new paradigm for exploring the underlying mechanisms of many cognitive functions based on non-equilibrium physics.
Connections of the Human Orbitofrontal Cortex and Inferior Frontal Gyrus.
Cerebral cortex (New York, N.Y. : 1991), 2020

The direct connections of the orbitofrontal cortex (OFC) were traced with diffusion tractography imaging and statistical analysis in 50 humans, to help understand better its roles in emotion and its disorders. The medial OFC and ventromedial prefrontal cortex have direct connections with the pregenual and subgenual parts of the anterior cingulate cortex; all of which are reward-related areas. The lateral OFC (OFClat) and its closely connected right inferior frontal gyrus (rIFG) have direct connections with the supracallosal anterior cingulate cortex; all of which are punishment or nonreward-related areas. The OFClat and rIFG also have direct connections with the right supramarginal gyrus and inferior parietal cortex, and with some premotor cortical areas, which may provide outputs for the OFClat and rIFG. Another key finding is that the ventromedial prefrontal cortex shares with the medial OFC especially strong outputs to the nucleus accumbens and olfactory tubercle, which comprise the ventral striatum, whereas the other regions have more widespread outputs to the striatum. Direct connections of the OFC and IFG were with especially the temporal pole part of the temporal lobe. The left IFG, which includes Broca's area, has direct connections with the left angular and supramarginal gyri.
Structural Mechanism of ω-Currents in a Mutated Kv7.2 Voltage Sensor Domain from Molecular Dynamics Simulations.
Journal of chemical information and modeling, 2021

Activation of voltage-gated ion channels is regulated by conformational changes of the voltage sensor domains (VSDs), four water- and ion-impermeable modules peripheral to the central, permeable pore domain. Anomalous currents, defined as ω-currents, have been recorded in response to mutations of residues on the VSD S4 helix and associated with ion fluxes through the VSDs. In humans, gene defects in the potassium channel Kv7.2 result in a broad range of epileptic disorders, from benign neonatal seizures to severe epileptic encephalopathies. Experimental evidence suggests that the R207Q mutation in S4, associated with peripheral nerve hyperexcitability, induces ω-currents at depolarized potentials, but the fine structural details are still elusive. In this work, we use atom-detailed molecular dynamics simulations and a refined model structure of the Kv7.2 VSD in the active conformation in a membrane/water environment to study the effect of R207Q and four additional mutations of proven clinical importance. Our results demonstrate that the R207Q mutant shows the most pronounced increase of hydration in the internal VSD cavity, a feature favoring the occurrence of ω-currents. Free energy and kinetics calculations of sodium permeation through the native and mutated VSD indicate as more favorable the formation of a cationic current in the latter. Overall, our simulations establish a mechanistic linkage between genetic variations and their physiological outcome, by providing a computational description that includes both thermodynamic and kinetic features of ion permeation associated with ω-currents.
Peripheral blood expression levels of inflammasome complex components in two different focal epilepsy syndromes.
Journal of neuroimmunology, 2020

Although the role of inflammation in epilepsy pathogenesis has been extensively investigated, the inflammasome complex, a key component of neuroinflammation, has been understudied in epilepsy patients.
Association between liver fibrosis and cognition in a nationally representative sample of older adults.
European journal of neurology, 2020

Liver fibrosis, a common yet often subclinical manifestation of chronic liver disease, may have an unrecognized role in cognitive impairment. We evaluated the association between a validated liver fibrosis index and cognitive measures among older adults.
Identification of the neural crest-specific enhancer of Seraf gene in avian peripheral nervous system development.
Biochemical and biophysical research communications, 2015

In vertebrate embryos, trunk neural crest cells give rise to Schwann cells, along with other derivatives. In this study, to elucidate the molecular mechanisms for the Schwann cell specification, we aimed to identify enhancer elements responsible for the expression of the Seraf gene, the earliest marker for the Schwann cell precursors in the avian embryos. We first compared the genomic structure around the Seraf locus in various vertebrates, and found that, while mammals do not have a Seraf homolog, teleost fish species have it. However, the intergenic sequences around the Seraf locus are not conserved between zebrafish and chicken, consistent with the fact that fish Seraf expression is not Schwann cell precursor-specific. We thus compared the intergenic sequences around the Seraf locus among avian species, and identified a potential enhancer containing a cluster of Sox10-binding sites. Accordingly, the identified enhancer is activated in a neural crest-specific manner in transfected quail embryos. We also found that Sox10 activated the enhancer in cultured cells. Thus, our results revealed a new role of Sox10 in the earliest phase of the Schwann cell fate specification.
Gender differences in adolescent sleep neurophysiology: a high-density sleep EEG study.
Scientific reports, 2020

During adolescence, differences between males and females in physiology, behavior and risk for psychopathology are accentuated. The goal of the current study was to examine gender differences in sleep neurophysiology using high-density sleep EEG in early adolescence. We examined gender differences in sleep EEG power and coherence across frequency bands for both NREM and REM sleep in a sample of 61 adolescents (31 girls and 30 boys; mean age = 12.48; SD = 1.34). In addition, sleep spindles were individually detected and characterized. Compared to boys, girls had significantly greater spindle activity, as reflected in higher NREM sigma power, spindle amplitude, spindle frequency and spindle density over widespread regions. Furthermore, power in higher frequency bands (16.2-44 Hz) was larger in girls than boys in a state independent manner. Oscillatory activity across frequency bands and sleep states was generally more coherent in females as compared to males, suggesting greater connectivity in females. An exception to this finding was the alpha band during NREM and REM sleep, where coherence was higher (NREM) or not different (REM) in boys compared to girls. Sleep spindles are generated through thalamocortical circuits, and thus, the greater spindle activity across regions in females may represent a stronger thalamocortical circuit in adolescent females as compared to males. Moreover, greater global connectivity in females may reflect functional brain differences with implications for cognition and mental health. Given the pronounced gender differences, our study highlights the importance of taking gender into account when designing and interpreting studies of sleep neurophysiology.
SuHeXiang Essential Oil Inhalation Produces Antidepressant- and Anxiolytic-Like Effects in Adult Mice.
Biological & pharmaceutical bulletin, 2018

SuHeXiang (SHX) has been used to treat a wide range of diseases, including those related to the central nervous system. However, the effects of SHX on mood disorders are still elusive. This study aimed to investigate the effects of SHX essential oil on stress-induced depression of mice. In an acute stress-induced depression model, mice inhaled vehicle (1% Tween 80) for 10 min or 10% SHX for 10 or 30 min once daily for 12 continuous days. In the chronic mild stress (CMS)-induced depression model, mice were exposed to a 28-d CMS treatment. Tail suspension test (TST), forced swimming test (FST), sucrose preference test (SPT), open field test (OFT), and novelty suppressed feeding (NSF) test were conducted. In addition, serum levels of angiogenin (ANG), thrombopoietin (TPO), interleukin 6 (IL-6), and tumor necrosis factor-α (TNF-α) were evaluated by enzyme-linked immunosorbent assay (ELISA) assays. The results showed that in mice exposed to acute stress, repeated SHX inhalation exerted significant antidepressant and anxiolytic activities, and also reduced the serum levels of ANG, TPO, IL-6, and TNF-α. It also significantly reversed the depressive and anxiety-like behaviors, and reduced the serum levels of ANG and TPO in mice exposed to CMS. This is the first report to show that SHX inhalation could produce significant antidepressant and anxiolytic-like effects. These effects might be mediated by SHX ability to modulate the inflammatory response, and reduce dysfunction of vascular genesis and thrombosis. These results support further exploration for developing SHX inhalation as a novel therapeutic strategy for depression and stress-related disorders.
Signal attenuation as a rat model of obsessive compulsive disorder.
Journal of visualized experiments : JoVE, 2015

In the signal attenuation rat model of obsessive-compulsive disorder (OCD), lever-pressing for food is followed by the presentation of a compound stimulus which serves as a feedback cue. This feedback is later attenuated by repeated presentations of the stimulus without food (without the rat emitting the lever-press response). In the next stage, lever-pressing is assessed under extinction conditions (i.e., no food is delivered). At this stage rats display two types of lever-presses, those that are followed by an attempt to collect a reward, and those that are not. The latter are the measure of compulsive-like behavior in the model. A control procedure in which rats do not experience the attenuation of the feedback cue serves to distinguish between the effects of signal attenuation and of extinction. The signal attenuation model is a highly validated model of OCD and differentiates between compulsive-like behaviors and behaviors that are repetitive but not compulsive. In addition the measures collected during the procedure eliminate alternative explanations for differences between the groups being tested, and are quantitative, unbiased and unaffected by inter-experimenter variability. The major disadvantages of this model are the costly equipment, the fact that it requires some technical know-how and the fact that it is time-consuming compared to other models of OCD (11 days). The model may be used for detecting the anti- or pro-compulsive effects of pharmacological and non-pharmacological manipulations and for studying the neural substrate of compulsive behavior.
Revised and Neuroimaging-Compatible Versions of the Dual Task Screen.
Journal of visualized experiments : JoVE, 2020

Dual task paradigms simultaneously assess motor and cognitive abilities, and they can detect subtle, residual impairments in athletes with recent mild traumatic brain injury (mTBI). However, past dual task paradigms have focused solely on lower extremity skills and have relied on cumbersome, expensive laboratory equipment - thus limiting their practicality for everyday mTBI evaluation. Subsequently, we developed the Dual Task Screen (DTS), which takes <10 minutes to administer and score, uses low-cost portable equipment, and includes lower extremity (LE) and upper extremity (UE) subtasks. The purpose of this manuscript was twofold. First, we describe the administration protocol for the revised DTS, which we revised to address the limitations of the original DTS. Specifically, the revisions included additions of smart devices to acquire more detailed gait data and inclusion of single cognitive conditions to test for disrupted cognitive performance under dual task conditions. Importantly, the revised DTS is a measure intended for future clinical use, and we present representative results from three male athletes to illustrate the type of clinical data that can be acquired from the measure. Importantly, we have yet to evaluate the sensitivity and specificity of the revised DTS in athletes with mTBI, which is the next research initiative. The second purpose of this manuscript is to describe a neuroimaging-compatible version of the DTS. We developed this version so we could evaluate the neural underpinnings of single and dual task performance, for a better empirical understanding of the behavioral deficits associated with mTBI. Thus, this manuscript also describes the steps we took to enable simultaneous functional near-infrared spectroscopy (fNIRS) measurement during the DTS, along with how we acquired and completed first-level processing of the fNIRS data.
Therapist-Supported Online Interventions for Children and Young People With Tic Disorders: Lessons Learned From a Randomized Controlled Trial and Considerations for Future Practice.
JMIR mental health, 2020

In recent years, research into internet-based cognitive behavioral therapy (iCBT) has suggested that therapist-guided digital interventions have greater engagement, adherence, and effectiveness than self-directed digital therapies. While research has focused on the effectiveness of, and adherence to, these interventions, less attention has been paid to their implementation in practice and what aspects of the therapist role support success. An understanding of the key factors related to the therapist role and intervention delivery is required if these iCBTs are to be applied in routine clinical care and outcomes optimized. In light of the coronavirus disease 2019 (COVID-19) pandemic, there is greater emphasis on allowing patients access to remote therapies. We report the experiences and reflections of 4 therapists and their 2 supervisors in delivering an online, therapist-supported intervention in a randomized controlled trial for children and young people with tic disorders (the Online Remote Behavioural Intervention for Tics [ORBIT] trial). Themes discussed include the importance of training, supervision, creating support documents/manuals, and record keeping. Alongside this are communication strategies used by therapists to encourage patient adherence and treatment effectiveness. These include rapport building, treatment personalization, and suggestions for overcoming non-engagement. These reflections offer important considerations for the delivery of iCBTs as well as implications associated with the implementation of these interventions in existing services and future research studies. We share thoughts on where iCBTs may sit in a stepped care model, how services may deal with comorbid conditions, and the potential role of iCBTs in collecting clinical data.
Core Alzheimer's disease cerebrospinal fluid biomarker assays are not affected by aspiration or gravity drip extraction methods.
Alzheimer's research & therapy, 2021

CSF biomarkers are well-established for routine clinical use, yet a paucity of comparative assessment exists regarding CSF extraction methods during lumbar puncture. Here, we compare in detail biomarker profiles in CSF extracted using either gravity drip or aspiration.
Emotional valence modulates arithmetic strategy execution in priming paradigm: an event-related potential study.
Experimental brain research, 2021

Combined with the prime paradigm, the present study aimed to explore the influence of emotion (anger, fear, happiness, and neutral) on performing multiplication estimation. Participants were asked to complete a two-digit multiplication estimation task using the down-up strategy (e.g., doing 20 × 80 = 1600 for 24 × 79). Behavioral results showed that the reaction time for completing multiplication estimation tasks under happy conditions was shorter than for those under anger and fear, and it was shorter under neutral than under fearful conditions. The ERP results showed that about 100 ms after multiplication estimation task onset, multiplication estimation execution in the context of happiness (vs. neutral) elicited smaller P1 amplitudes; about 170 ms after multiplication estimation task onset, the N170 amplitudes elicited by multiplication estimation strategy execution under different emotional priming conditions showed no significant differences. The above results showed that the impact of emotion priming demonstrates the occurrence of a dynamic process when participants use a specified strategy to complete the multiplication estimation task. The present study revealed that emotional valence modulated arithmetic strategy execution, suggesting the role of different emotions should be fully considered in similar study.
Bimodal Benefits Revealed by Categorical Perception of Lexical Tones in Mandarin-Speaking Kindergarteners With a Cochlear Implant and a Contralateral Hearing Aid.
Journal of speech, language, and hearing research : JSLHR, 2020

Purpose Pitch reception poses challenges for individuals with cochlear implants (CIs), and adding a hearing aid (HA) in the nonimplanted ear is potentially beneficial. The current study used fine-scale synthetic speech stimuli to investigate the bimodal benefit for lexical tone categorization in Mandarin-speaking kindergarteners using a CI and an HA in opposite ears. Method The data were collected from 16 participants who were required to complete two classical tasks for speech categorical perception (CP) with CI + HA device condition and CI alone condition. Linear mixed-effects models were constructed to evaluate the identification and discrimination scores across different device conditions. Results The bimodal kindergarteners showed CP for the continuum varying from Mandarin Tone 1 and Tone 2. Moreover, the additional acoustic information from the contralateral HA contributes to improved lexical tone categorization, with a steeper slope, a higher discrimination score of between-category stimuli pair, and an improved peakedness score (i.e., an increased benefit magnitude for discriminations of between-category over within-category pairs) for the CI + HA condition than the CI alone condition. The bimodal kindergarteners with better residual hearing thresholds at 250 Hz level in the nonimplanted ear could perceive lexical tones more categorically. Conclusion The enhanced CP results with bimodal listening provide clear evidence for the clinical practice to fit a contralateral HA in the nonimplanted ear in kindergarteners with unilateral CIs with direct benefits from the low-frequency acoustic hearing.