Hasil untuk "Neurophysiology and neuropsychology"

Maryam Azfar, Tayyba Mirza, Elif Baykal et al.

Although managerial support has long been acknowledged as an important resource in organizations, the mechanisms through which it translates into stronger affective organizational commitment remain underexplored. Past literature has mainly investigated the direct effects, overlooking the sequential psychological processes that sustain employee commitment. By integrating prosocial motivation as a first-level mediator and collective thriving as a second-level mediator, we address this critical gap. A 2-week time-lagged structure was utilized to gather information from 586 employees working in 76 teams across several industries in Pakistan. The direct and indirect effects between managerial support and affective commitment were evaluated using the Process Hayes Model 6. The study’s findings indicate that managerial support promotes prosocial motivation among employees. The finding also demonstrated that support from the manager promotes collective thriving and ultimately the sense of affective organizational commitment. The present study advances theoretical knowledge of how managerial support fosters affective organizational commitment but also offers actionable insights for top management seeking to enhance employee commitment through prosocial motivation and collective thriving paths. Furthermore, as our data were collected from a single country, cross-cultural research on study constructs remains limited, and further studies conducted in different cultural settings are strongly encouraged.

Magdalena Wszędybył-Winklewska, Ewelina Czuba-Pakuła, Krzysztof S. Malinowski et al.

Abstract Mild hypoxia is a common condition encountered in various situations, such as high-altitude living, respiratory diseases, anaemia, and certain cardiovascular disorders. At the same time, mild hypoxia often goes unnoticed and can lead to long-term brain impairments. Understanding the subtle effects of mild hypoxia on the brain is essential for early diagnosis and intervention to prevent serious neurological and psychiatric complications. The pathophysiology of mild chronic hypoxia is complex; nevertheless, based on the literature, two main pathways can be distinguished. The first involves the direct effects of mild hypoxia on the brain and spinal cord, while the second involves the influence of enhanced systemic inflammation. In this narrative review, we discuss the current understanding of the effects of mild hypoxia on brain metabolism, cellular models, perfusion, the blood–brain barrier (BBB), the blood–spinal cord barrier (BSCB) and the brain-cerebrospinal fluid barrier (BCSFB). We explore the intricate relationship between peripheral inflammation induced by hypoxia and the BBB/BSCB/BCSFB, shedding light on the underlying mechanisms and their potential implications for central nervous system health. Graphical abstract

Stucky B

Benjamin Stucky Institute of Pharmacology and Toxicology, University of Zurich, Zurich, SwitzerlandCorrespondence: Benjamin Stucky, Institute of Pharmacology and Toxicology University of Zurich, Winterthurerstrasse 190 CH-8057, Zurich, Switzerland, Email benjamin.stucky@pharma.uzh.chPurpose: Since the 1930s, researchers have awakened people from different stages of sleep to record what they have experienced. While some aspects, including asking whether participants had dreams or thoughts before awakening, largely remain the same, others, such as the method of awakening, vary greatly. In addition, it is often assumed that the influence of participant characteristics, such as personality traits, motivation, memory, and attention, is reduced by collecting experiences immediately after they occur, rather than through delayed morning recall. However, the extent to which these variables influence dream recall upon awakening has not yet been thoroughly investigated.Materials and Methods: To explore possible contextual and individual influences, this review analyzed 69 awakening studies conducted between 2000 and 2024 and utilized the DREAM database. Differences between sleep stages were quantified and experiences analyzed using the categories “with recall”, “without recall”, and “no report”.Results: Similar levels of null reports were found in NREM stage 2 and stage 3. Significant factors affecting dream recall included the method of awakening (lower recall with an alarm compared to calling the participant’s name), the number of study days (reduced recall for multiple days) and the sleep environment (higher recall at home compared to the laboratory), along with participant characteristics beyond age, sex and study design. Recall rates from NREM sleep are particularly sensitive to the method of awakening and interindividual differences.Conclusion: Both the awakening procedure and participant characteristics influence the amount of reported sleep experiences, which can impact study outcomes, such as the identification of neural correlates of consciousness. Therefore, greater emphasis needs to be placed on how experiences are collected and on participant characteristics, such as openness to experience or familiarity with different states of consciousness.Plain Language Summary: Have you ever wondered how often you dream while you sleep? We reviewed 69 studies where people were woken up to share their experiences. They reported dreaming most of the time, even in deep sleep. You might ask, “Why don’t I remember much in the morning then?” Well, maybe you forgot your dream because a lot of time has passed. These studies capture the experience right after it happens, but even then, some people remember dreams more than others. This could be because they are more focused on their dreams. How you wake up also matters. If someone shakes you awake, you may forget your dream, but if they gently call your name, you have a better chance of remembering it. You might also fail to recognize more subtle experiences, such as a sense of calm. So perhaps sleep is not as unconscious as we thought, leaving much to be explored in future studies.Keywords: dreaming, serial awakenings, experience, awareness, memory, attention, questionnaire, phenomenology

He C, Wang B, Chen X et al.

Caijun He,1 Biao Wang,1 Xuanyu Chen,1 Jiacheng Xu,2 Yaxin Yang,1 Mei Yuan1,2 1Department of Neurology, Hengyang Medical School, The Second Affiliated Hospital, University of South China, Hengyang, 421001, People’s Republic of China; 2Department of Neurology, Hengyang Medical School, Affiliated Nanhua Hospital, University of South China, Hengyang, 421001, People’s Republic of ChinaCorrespondence: Mei Yuan, Department of Neurology, Hengyang Medical School, Affiliated Nanhua Hospital, University of South China, Hengyang, 421001, People’s Republic of China, Email 2012020002@usc.edu.cnAbstract: Sleep is a highly elaborate biological occurrence, necessitating the combined action and participation of diverse brain regions. The sleep-wake cycle is regulated by a multitude of factors, including various hormones produced by the hypothalamus and external stimuli. Sleep disorders can accelerate the progression of numerous diseases or directly trigger the onset of many health conditions. However, the specific regulatory mechanisms remain elusive. In recent years, the role of magnesium in sleep disorders has garnered considerable attention. Magnesium not only reduces the excitability of the nervous system and alters muscle relaxation but also regulates cellular biological clocks, energy balance, and circadian rhythms, playing a crucial role in sleep regulation. Magnesium deficiency not only shortens the effective sleep duration but also impairs sleep quality, leading to various specific sleep disorders. Additionally, magnesium supplements can improve sleep parameters in a variety of sleep-related diseases, especially those associated with the occurrence and development of sleep disorders. Therefore, a more in-depth understanding of the impact of magnesium on sleep disorders may reveal new therapeutic targets for sleep-related diseases. In this review, we comprehensively summarize the latest key findings on the mechanism of action of magnesium in sleep health and its role in initiating or exacerbating common sleep disorders, providing new insights into the diagnosis and treatment of sleep disorder-related diseases.Keywords: magnesium, sleep, sleep disorder

Motomura Y, Kitamura S, Oba K et al.

Yuki Motomura,1,2 Shingo Kitamura,1 Kentaro Oba,1,3 Ruri Katsunuma,1 Yuri Terasawa,1,4 Akiko Hida,1 Yoshiya Moriguchi,1,5 Kazuo Mishima1,6 1Department of Sleep-Wake Disorders, National Institute of Mental Health, National Center of Neurology and Psychiatry Tokyo Japan; 2Department of Human Life Design and Science, Faculty of Design, Kyushu University, Fukuoka, Japan; 3Smart Aging Research Center, Tohoku University, Miyagi, Japan; 4Department of Psychology, Keio University, Kanagawa, Japan; 5Development Center, Lundbeck, Japan, Tokyo, Japan; 6Department of Neuropsychiatry, Akita University Graduate School of Medicine, Akita, JapanCorrespondence: Yuki Motomura, Faculty of Design, Kyushu University, 4-9-1 Shiobaru, Minami-ku, Fukuoka, 815-8540, Japan, Email motomura@design.kyushu-u.ac.jp Kazuo Mishima, Department of Neuropsychiatry, Akita University Graduate School of Medicine, 1-1 Tegatagakuen-machi, Akita-shi, Akita, Japan, Email clocksclub@gmail.comPurpose: This study examined the neural correlates in functional brain connectivity common to subjective and objective sleepiness. Because functional connectivity can be measured at rest and during tasks, it is well suited for exploring the commonalities between sleepiness during psychomotor vigilance task (PVT) and at rest with measurement of The Karolinska Sleepiness Scale (KSS). Serial resting and task-based fMRI measurements across various states of arousal may reveal a common neural substrate that does not vary with task demands. The neural basis shared by the PVT, an objective measure highly sensitive to sleep debt, and subjective reports of sleepiness may be robust markers for sleepiness and contribute to an improved understanding of the brain mechanisms underlying sleepiness.Participants and Methods: The participants were 16 healthy right-handed (self-reported) adult men who, after a 2-week home examination, participated in a 14-day/13-night experiment that included 9 days of extended sleep (12 h per night), followed by one night of total sleep deprivation (0 h), and recovery sleep. KSS and the PVT were used as subjective and objective measures of sleepiness, respectively. Functional connectivity in the brain during each condition were measured using fMRI. In particular, the association between the inverse of the reaction time to the PVT task and resting-state functional connectivity was analyzed using a general linear mixed model.Results: Functional connectivity in six pairs of regions commonly associated with the KSS and PVT were identified. These included the anterior cingulate cortex-posterior cingulate cortex (part of the default mode network) and thalamus-middle temporal cortex, indicating that connectivity in these brain regions were strongly associated with sleepiness.Conclusion: These results suggest a common neural substrate for subjective and objective sleepiness, which may be an important indicator of sleepiness. In addition, the functional connectivity between the thalamus and the middle temporal cortex may be a new network that deserves further attention in sleep research. The results of this study provide valuable insights into the effects of sleep deprivation and total sleep deprivation experienced in daily life on the brain and offer a new perspective on the expression of sleepiness in the brain.Keywords: functional connectivity, sleepiness, psychomotor vigilance task, default mode network, middle temporal cortex, thalamus

Alberto Raiola, Emanuele Locatelli, Davide Marenduzzo et al.

Magnetic polymers are examples of composite soft materials in which the competition between the large configurational entropy of the soft substrate (polymer) and the magnetic interaction may give rise to rich equilibrium phase diagrams as well as non-standard critical phenomena. Here, we study a self-avoiding walk model decorated by Ising spins of value $0$ and $\pm 1$ that interact according to a Blume-Emery-Griffith-like Hamiltonian. By using mean-field approximations and Monte Carlo simulations, we report the existence of three distinct equilibrium phases: swollen disordered, compact ordered, and compact disordered. Notably, these phases are separated by phase boundaries that meet at multicritical points, whose nature and location are tunable and depend on the strength of the interactions. In our conclusion, we discuss the relevance of the phase diagrams we have obtained to the physics of magnetic polymers and their application to chromatin biophysics.

Zachary L. Crang, Rich D. Johnston, Katie L. Mills et al.

This study aimed to: (1) understand whether commercially available computer-vision and artificial intelligence (AI) player tracking software can accurately measure player position, speed and distance using broadcast footage and (2) determine the impact of camera feed and resolution on accuracy. Data were obtained from one match at the 2022 Qatar Federation Internationale de Football Association (FIFA) World Cup. Tactical, programme and camera 1 feeds were used. Three commercial tracking providers that use computer-vision and AI participated. Providers analysed instantaneous position (x, y coordinates) and speed (m\,s^{-1}) of each player. Their data were compared with a high-definition multi-camera tracking system (TRACAB Gen 5). Root mean square error (RMSE) and mean bias were calculated. Position RMSE ranged from 1.68 to 16.39 m, while speed RMSE ranged from 0.34 to 2.38 m\,s^{-1}. Total match distance mean bias ranged from -1745 m (-21.8%) to 1945 m (24.3%) across providers. Computer-vision and AI player tracking software offer the ability to track players with fair precision when players are detected by the software. Providers should use a tactical feed when tracking position and speed, which will maximise player detection, improving accuracy. Both 720p and 1080p resolutions are suitable, assuming appropriate computer-vision and AI models are implemented.

Maggie Barker, Daniel Guo, Justin Palmeri et al.

In the paper, a program strength model was proposed to evaluate the performance of countries across different Olympic events. The model assessed how strong a country's program was in each event and also factored in the influence of past Olympic performances. The final medal counts from the Paris 2024 Olympic Games were used to validate the model and to determine the optimal set of constants using Monte Carlo simulation. Based on this model, a prediction of the final medal counts for the 2028 Olympic Games is also provides for reference.

Leo Westebbe, Yibiao Liang, Erik Blaser

Zecheng Yin, Chonghao Cheng, and Yao Guo et al.

Navigating towards fully open language goals and exploring open scenes in an intelligent way have always raised significant challenges. Recently, Vision Language Models (VLMs) have demonstrated remarkable capabilities to reason with both language and visual data. Although many works have focused on leveraging VLMs for navigation in open scenes, they often require high computational cost, rely on object-centric approaches, or depend on environmental priors in detailed human instructions. We introduce Navigation with VLM (NavVLM), a training-free framework that harnesses open-source VLMs to enable robots to navigate effectively, even for human-friendly language goal such as abstract places, actions, or specific objects in open scenes. NavVLM leverages the VLM as its cognitive core to perceive environmental information and constantly provides exploration guidance achieving intelligent navigation with only a neat target rather than a detailed instruction with environment prior. We evaluated and validated NavVLM in both simulation and real-world experiments. In simulation, our framework achieves state-of-the-art performance in Success weighted by Path Length (SPL) on object-specifc tasks in richly detailed environments from Matterport 3D (MP3D), Habitat Matterport 3D (HM3D) and Gibson. With navigation episode reported, NavVLM demonstrates the capabilities to navigate towards any open-set languages. In real-world validation, we validated our framework's effectiveness in real-world robot at indoor scene.

Clotilde Turpin, Olivier Rossel, Félix Schlosser-Perrin et al.

Objective: Direct cortical responses (DCR) and axono-cortical evoked potentials (ACEP) are generated by electrically stimulating the cortex either directly or indirectly through white matter pathways, potentially leading to different electrogenic processes. For ACEP, the slow conduction velocity of axons (median around 4 m.s$^{-1}$) is anticipated to induce a delay. For DCR, direct electrical stimulation (DES) of the cortex is expected to elicit additional cortical activity involving smaller and slower non-myelinated axons. We tried to validate these hypotheses. Methods: DES was administered either directly on the cortex or to white matter fascicles within the resection cavity, while recording DCR or ACEP at the cortical level in nine patients. Results: Short but significant delays (around 2 ms) were measurable for ACEP immediately following the initial component (around 7 ms). Subsequent activities (around 40 ms) exhibited notable differences between DCR and ACEP, suggesting the presence of additional cortical activities for DCR. Conclusion: Distinctions between ACEPs and DCRs can be made based on a delay at the onset of early components and the dissimilarity in the shape of the later components >40 ms after the DES artifact). Significance: The comparison of different types of evoked potentials allows to better understand the effects of DES.

Taghreed Ahmed, Ahmed Younes, and Islam Elkabani

The construction of quantum computers is based on the synthesis of low-cost quantum circuits. The quantum circuit of any Boolean function expressed in a Positive Polarity Reed-Muller $PPRM$ expansion can be synthesized using Multiple-Control Toffoli ($MCT$) gates. This paper proposes two algorithms to construct a quantum circuit for any Boolean function expressed in a Positive Polarity Reed-Muller $PPRM$ expansion. The Boolean function can be expressed with various algebraic forms, so there are different quantum circuits can be synthesized for the Boolean function based on its algebraic form. The proposed algorithms aim to map the $MCT$ gates into the $NCV$ gates for any quantum circuit by generating a simple algebraic form for the Boolean function. The first algorithm generates a special algebraic form for any Boolean function by rearrangement of terms of the Boolean function according to a predefined degree of term $d_{term}$, then synthesizes the corresponding quantum circuit. The second algorithm applies the decomposition methods to decompose $MCT$ circuit into its elementary gates followed by applying a set of simplification rules to simplify and optimize the synthesized quantum circuit. The proposed algorithms achieve a reduction in the quantum cost of synthesized quantum circuits when compared with relevant work in literature. The proposed algorithms synthesize quantum circuits that can applied on IBM quantum computer.

Roman Tikhonov, Simon DeDeo

Alexis Brieant, Anna Vannucci, Hajer Nakua et al.

Early-life adversity has profound consequences for youth neurodevelopment and adjustment; however, experiences of adversity are heterogeneous and interrelated in complex ways that can be difficult to operationalize and organize in developmental research. We sought to characterize the underlying dimensional structure of co-occurring adverse experiences among a subset of youth (ages 9–10) from the Adolescent Brain Cognitive Development (ABCD) Study (N = 7115), a community sample of youth in the United States. We identified 60 environmental and experiential variables that reflect adverse experiences. Exploratory factor analysis identified 10 robust dimensions of early-life adversity co-occurrence, corresponding to conceptual domains such as caregiver substance use and biological caregiver separation, caregiver psychopathology, caregiver lack of support, and socioeconomic disadvantage / neighborhood lack of safety. These dimensions demonstrated distinct associations with internalizing problems, externalizing problems, cognitive flexibility, and inhibitory control. Non-metric multidimensional scaling characterized qualitative similarity among the 10 identified dimensions. Results supported a nonlinear three-dimensional structure representing early-life adversity, including continuous gradients of “perspective”, “environmental uncertainty”, and “acts of omission/commission”. Our findings suggest that there are distinct dimensions of early-life adversity co-occurrence in the ABCD sample at baseline, and the resulting dimensions may have unique implications for neurodevelopment and youth behavior.

Allen Joshua George, Romate John, Eslavath Rajkumar et al.

AbstractBoth hedonia and eudaimonia contribute to well-being, but existing literature on alcohol-dependence concentrates on hedonic needs alone, leaving a research gap on the role of eudaimonia in alcohol-dependence. Theoretically, mindfulness promotes eudaimonia that presumably benefits individuals with alcohol-dependence, but the empirical literature on the same is scarce. Hence, the current pilot study intended to examine the association of eudaimonia and mindfulness with alcohol-dependence, and assess the feasibility of the main study. Study-I compared mindfulness and eudaimonia of individuals with (N = 154) and without (N = 160) alcohol-dependence. Its results called forth a study-II that explored the role of eudaimonia and mindfulness in predicting alcohol-dependence among the individuals undergoing treatment for alcohol-dependence (N = 110). The data were analyzed using the independent-sample t-test, Pearson correlation, and multiple linear regression. Study-I revealed the significant deficiency of mindfulness and eudaimonia among individuals with alcohol-dependence compared to those without alcohol-dependence. Study-II found that mindfulness and eudaimonia predicted alcohol-dependence and alcohol craving. Study result indicates the potential role of mindfulness and eudaimonia in the effective treatment of alcohol-dependence, through significant correlation among the variables. The study also highlights the feasibility and utility of the main study.

Martin V. Sale, Anastasiia Kuzovina

Abstract Physical exercise and neurorehabilitation involve repetitive training that can induce changes in motor performance arising from neuroplasticity. Retention of these motor changes occurs via an encoding process, during which rapid neuroplastic changes occur in response to training. Previous studies show that transcranial alternating current stimulation (tACS), a form of non-invasive brain stimulation, can enhance encoding of a cognitive learning task during wakefulness. However, the effect of tACS on motor processes in the awake brain is unknown. In this study, forty-two healthy 18–35 year old participants received either 0.75 Hz (active) tACS (or sham stimulation) for 30 min during a ballistic thumb abduction motor training task. Training-related behavioural effects were quantified by assessing changes in thumb abduction acceleration, and neuroplastic changes were quantified by measuring motor evoked potential (MEP) amplitude of the abductor pollicis brevis muscle. These measures were reassessed immediately after the motor training task to quantify short-term changes, and then 24 h later to assess longer-term changes. Thumb abduction acceleration in both active and sham stimulation conditions increased immediately after the motor learning, consistent with effective training. Critically, participants in the active group maintained significantly higher thumb acceleration 24 h later (t40 = 2.810, P = 0.044). There were no significant changes or inter-group differences in MEPs for both conditions. The results suggest that 0.75 Hz tACS applied during motor training enhances the effectiveness of motor training, which manifests as enhancement in longer-term task benefits.

Danna Pinto, Anat Prior, Elana Zion Golumbic

Rajni Farmania, Ankit Gupta, Kumar Ankur et al.

Pyridox(am)ine- 5- phosphate Oxidase deficiency (PNPO) is a rare cause of neonatal metabolic encephalopathy associated with refractory status epilepticus. We report a case of a premature neonate presenting with drug-resistant seizures beginning at 2 hours of life. The baby showed initial transient response to pyridoxine followed by recurrence. Genetic report confirmed the diagnosis of PNPO deficiency. A literature review on phenotypic variants in terms of response to pyridoxine is also presented along with a proposed algorithm to manage a case of suspected vitamin responsive epilepsy. This case highlights our limited understanding of why variation in response to treatment exists in children with PNPO deficiency.

Jennifer Zuk, Xi Yu, Joseph Sanfilippo et al.

Language acquisition is of central importance to child development. Although this developmental trajectory is shaped by experience postnatally, the neural basis for language emerges prenatally. Thus, a fundamental question remains: do structural foundations for language in infancy predict long-term language abilities? Longitudinal investigation of 40 children from infancy to kindergarten reveals that white matter in infancy is prospectively associated with subsequent language abilities, specifically between: (i) left arcuate fasciculus and phonological awareness and vocabulary knowledge, (ii) left corticospinal tract and phonological awareness, and bilateral corticospinal tract with phonological memory; controlling for age, cognitive, and environmental factors. Findings link white matter in infancy with school-age language abilities, suggesting that white matter organization in infancy sets a foundation for long-term language development.

Tomoyoshi Shimobaba, Sota Oshima, Takashi Kakue et al.

Holographic information hiding is a technique for embedding holograms or images into another hologram, used for copyright protection and steganography of holograms. Using deep neural networks, we offer a way to improve the visual quality of embedded holograms. The brightness of an embedded hologram is set to a fraction of that of the host hologram, resulting in a barely damaged reconstructed image of the host hologram. However, it is difficult to perceive because the embedded hologram's reconstructed image is darker than the reconstructed host image. In this study, we use deep neural networks to restore the darkened image.