Hasil untuk "Neurophysiology and neuropsychology"

Max Kaufmann, David Lindner, Roland S. Zimmermann et al.

Chain-of-Thought (CoT) monitoring, in which automated systems monitor the CoT of an LLM, is a promising approach for effectively overseeing AI systems. However, the extent to which a model's CoT helps us oversee the model - the monitorability of the CoT - can be affected by training, for instance by the model learning to hide important features of its reasoning. We propose and empirically validate a conceptual framework for predicting when and why this occurs. We model LLM post-training as an RL environment where the reward decomposes into two terms: one term depending on final outputs and another term depending on the CoT. Our framework allows us to classify these two terms as "aligned", "orthogonal", or "in-conflict" before training. We predict that training with in-conflict terms will reduce monitorability, orthogonal terms will not affect it, and aligned terms will improve it. To validate our framework, we use it to classify a set of RL environments, train LLMs within those environments, and evaluate how training affects CoT monitorability. We find that (1) training with "in-conflict" reward terms reduces CoT monitorability and (2) optimizing in-conflict reward terms is difficult.

Nir Shimony, S. Weatherspoon, Emily Hanzlik et al.

Background Epilepsy is a common and frequently debilitating manifestation of pediatric brain tumors, especially low-grade epilepsy-associated tumors (LEATs) such as gangliogliomas, DNETs, and PXAs. In many children, seizures are the presenting symptom and may evolve into intractable epilepsy, affecting neurocognitive development and quality of life. Understanding the relationship between tumor biology, epileptogenic networks, and clinical presentation is essential for guiding timely and effective management. Summary This review synthesizes current evidence and expert consensus on the integrated management of tumor-related epilepsy in children. We describe the anatomical, histopathological, and molecular correlates of epileptogenicity in pediatric brain tumors, with particular attention to the distinct clinical behavior of LEATs. Diagnostic strategies, including advanced imaging, neurophysiology, and invasive monitoring, are reviewed in the context of localizing the seizure onset zone while preserving function. The review outlines the indications and strategies for early surgical intervention, emphasizing that seizure control should be viewed as a primary therapeutic goal rather than a secondary outcome of tumor resection. Surgical approaches are discussed in relation to epilepsy duration, tumor location, and electroclinical concordance. For early, well-localized cases, lesionectomy may be sufficient, while longstanding epilepsy or tumors near eloquent cortex often require epilepsy-directed resections guided by intracranial monitoring. The role of preoperative ancillary tests (such as MEG, TMS, and neuropsychology) and intraoperative techniques (including ECoG and IONM) is highlighted for improving safety and precision. Key Messages • Epilepsy is a significant contributor to morbidity in children with brain tumors, particularly LEATs. • Multidisciplinary care is essential for seizure localization and for optimizing outcomes in children with tumor-related epilepsy. • Early surgical intervention is associated with better seizure and cognitive outcomes. • Delayed treatment increases the risk of secondary epileptogenesis and long-term developmental effects. • Individualized surgical planning should balance oncologic and epilepsy goals from the first clinical encounter. • Ancillary diagnostic and intraoperative tools enhance safety and help achieve maximal functional preservation.

Paul A Soden, Anjali Bhat, Adam K. Anderson et al.

Autistic meltdowns are fits of intense frustration and often physical violence elicited by sensory and cognitive stressors. Despite the high prevalence of meltdowns among autistic individuals, the neural mechanisms that underlie this response are not yet well understood. This has thus far hampered progress toward a dedicated therapeutic intervention-beyond traditional medications-that limits their frequency and severity. Here, we aim to initiate an interdisciplinary dialogue on the etiology of sensory meltdowns. In doing so, we frame meltdowns as a consequence of underlying chronic hypervigilance and acute hyperreactivity to objectively benign stressors driven by differences in the insular cortex-a multimodal integration hub that adapts autonomic state and behavior to meet environmental demands. We first discuss meltdowns through the lens of neurophysiology and argue that intrainsular hypoconnectivity engenders vagal withdrawal and sympathetic hyperarousal in autism, driving chronic hypervigilance and reducing the threshold of stressors those with autism can tolerate before experiencing a meltdown. Next, we turn to neuropsychology and present evidence that meltdowns reflect a difference in how contextual evidence, particularly social cues, is integrated when acutely assessing ambiguous signs of danger in the environment-a process termed neuroception. Finally, we build on contemporary predictive coding accounts of autism to argue that meltdowns may be ultimately driven by differences in sensory attenuation and coherent deep inference within the interoceptive hierarchy, possibly linked to oxytocin deficiency during infancy. Throughout, we synthesize each perspective to construct a multidisciplinary, insula-based model of meltdowns. (PsycInfo Database Record (c) 2025 APA, all rights reserved).

R. Hardstone, Lauren M Ostrowski, A. N. Dusang et al.

Focal brain lesions cause neurophysiological changes in local and distributed neural systems. While electroencephalography (EEG) has a long history in post-stroke neurophysiological assessment, the observed changes have rarely been linked to specific lesion locations, leaving neuroanatomical-neurophysiological relationships after stroke unclear. Current data-driven methods, such as voxel-based lesion symptom mapping (VLSM), relate lesion locations to single-feature “symptoms” but currently cannot associate anatomical injury with multidimensional data such as EEG, with its rich spatiotemporal information. To overcome this limitation, we introduce MD-VLM, an extension of VLSM to multidimensional “symptoms” that identifies relationships between lesion locations and neurophysiology. MD-VLM is data-agnostic, compatible with various lesion (e.g., lesion maps, lesion network maps) and neurophysiological (e.g., channel-level or source-localized EEG) inputs, and uses robust statistics to test for the existence of significant neuroanatomical-neurophysiological relationships. We demonstrate MD-VLM’s feasibility by applying it to EEG from chronic stroke patients performing a cued-movement task. MD-VLM revealed significant associations between frontal white-matter lesions and reduced ipsilesional parietal cue-evoked responses, consistent with damage to known fronto-parietal networks. MD-VLM is a novel data-driven extension to VLSM for multidimensional “symptoms”. Applying MD-VLM to link lesions to neurophysiological data can improve mechanistic understanding of post-stroke neurological impairments and guide future biomarker development.

Yuqing Lei, John Richards, Fengji Geng et al.

The emergence of source memory is an important milestone during memory development. Decades of research has explored neural correlates of source memory using electroencephalography (EEG) and functional magnetic resonance imaging (fMRI). However, connections between findings from the two approaches, particularly within children, remain unclear. This study identified fMRI-informed cortical sources of two EEG signals during memory encoding, the P2 and the late slow wave (LSW), that predicted subsequent source memory performance in a sample of children aged 4 to 8 years. Both P2 and LSW were source localized to cortical areas of the medial temporal lobe (MTL), reflecting MTL’s crucial role in both early-stage information processing and late-stage integration of memory, and validating LSW’s suspected role in memory updating. The P2 effect was localized to all six tested subregions of cortical MTL in both left and right hemispheres, whereas the LSW effect was only localized to the parahippocampal cortex and entorhinal cortex. P2 was additionally localized to multiple areas in the frontoparietal network, suggesting interactions between memory encoding and other cognitive functions. These results reflect the importance and potential of considering both spatial and temporal aspects of neural activity to decode memory mechanisms, paving the way for future developmental research.

Bo Ma, LuYao Liu, Simon Lau et al.

Recent research has explored using Large Language Models for recommendation tasks by transforming user interaction histories and item metadata into text prompts, then having the LLM produce rankings or recommendations. A promising approach involves connecting collaborative filtering knowledge to LLM representations through compact adapter networks, which avoids expensive fine-tuning while preserving the strengths of both components. Yet several challenges persist in practice: collaborative filtering models often use static snapshots that miss rapidly changing user preferences; many real-world items contain rich visual and audio content beyond textual descriptions; and current systems struggle to provide trustworthy explanations backed by concrete evidence. Our work introduces \model{}, a framework that tackles these limitations through three key innovations. We develop an online adaptation mechanism that continuously incorporates new user interactions through lightweight modules, avoiding the need to retrain large models. We create a unified representation that seamlessly combines collaborative signals with visual and audio features, handling cases where some modalities may be unavailable. Finally, we design an explanation system that grounds recommendations in specific collaborative patterns and item attributes, producing natural language rationales users can verify. Our approach maintains the efficiency of frozen base models while adding minimal computational overhead, making it practical for real-world deployment.

Jpa Education and Research Committee, Yoko Okamura, Ryuta Ochi et al.

Vasyl Fazan, Tetiana Fazan, Vitaliy Fazan et al.

The purpose of the article is to analyse the impact of the digital transformation of education on the cognitive load of students of higher education institutions, taking into account neurophysiological factors. Methodology. The study used general scientific methods (analysis, synthesis, comparison, generalisation, systematisation) to study the scientific literature on the issue. The methodological basis is an interdisciplinary approach that combines pedagogical experience, neuropsychology, and cognitive ergonomics. The empirical part of the study contains the results of a survey of 50 students from V.G. Korolenko Poltava National Pedagogical University, Ukraine. We also used comparative analysis, structural methods and modelling of the integration of Cyber-Human Systems technologies into the educational process. Results. The analysis of the survey results shows that the vast majority of respondents consider the digital learning format to be a factor in increasing cognitive and psycho-emotional stress. This way, 80% of participants noted its increase compared to traditional forms, which correlates with the findings of neuropsychological studies on the negative impact of multichannel information delivery and high content dynamics on attention span and brain performance. At the same time, 76% of respondents acknowledged the positive impact of digital learning on the development of creativity and critical thinking, which is explained by the possibility of using interactive platforms, project work, and problem-based research tasks. The most effective strategies for reducing cognitive load are the use of interactive methods (41%) and a rational balance between work and rest (32%). Reducing the duration of classes (15%) and psychological support of teachers (12%) are considered as secondary, but no less important measures. Conclusions. We have found based on the theoretical analysis and empirical results of the study that the process of digitalisation of education in higher education institutions is accompanied by significant neurophysiological challenges associated with an increase in the cognitive load on higher education students. The identified trends make it possible to understand the need for a rational, systematic approach to determining the volume, structure, and pace of the educational material, taking into account the recommendations of modern cognitive psychology and neurophysiology. Only under the specified conditions it is possible to create an effective and safe educational space for students.

Leonardo S. Novaes, Leticia M. Bueno-de-Camargo, Amadeu Shigeo-de-Almeida et al.

Anxiety, a state related to anticipatory fear, can be adaptive in the face of environmental threats or stressors. However, anxiety can also become persistent and manifest as anxiety- and stress-related disorders, such as generalized anxiety or post-traumatic stress disorder (PTSD). In rodents, systemic administration of glucocorticoids (GCs) or short-term restraint stress induces anxiety-like behaviors and dendritic branching within the basolateral complex of the amygdala (BLA) ten days later. Additionally, increased arousal-related memory retention mediated by elevated GCs requires concomitant noradrenaline (NE) signaling, both acting in the BLA. It is unknown whether GCs and NE play a role in the delayed acute stress-induced effects on behavior and BLA dendritic plasticity. Here, inhibiting corticosterone (CORT) elevation during 2 h of restraint stress prevents stress-induced increases in delayed anxiety-like behavior and BLA dendritic spine density in rats. Also, we show that the delayed acute stress-induced effects on behavior and morphological alterations are critically dependent on genomic glucocorticoid receptor (GR) actions in the BLA. Unlike CORT, the pharmacological enhancement of NE signaling in the BLA was insufficient to drive delayed anxiety-related behavior. Nonetheless, the delayed anxiety-like behavior ten days after acute stress requires NE signaling in the BLA during stress exposure. Therefore, we define the essential roles of two stress-related hormones for the late stress consequences, acting at two separate times: CORT, via GR, immediately during stress, and NE, via beta-adrenoceptors, during the expression of delayed anxiety.

Nuermaimaiti Q, Heizhati M, Luo Q et al.

Qiaolifanayi Nuermaimaiti,1– 6,&ast; Mulalibieke Heizhati,1– 6,&ast; Qin Luo,1– 6 Nanfang Li,1– 6 Lin Gan,1– 6 Ling Yao,1– 6 Wenbo Yang,1– 6 Mei Li,1– 6 Xiufang Li,1– 6 Xiayire Aierken,1– 6 Jing Hong,1– 6 Hui Wang,1– 6 Miaomiao Liu,1– 6 Adalaiti Maitituersun,1– 6 Aketilieke Nusufujiang,1– 6 Li Cai1– 6 1Hypertension Center of People’s Hospital of Xinjiang Uygur Autonomous Region, Urumqi, Xinjiang, 830001, People’s Republic of China; 2Xinjiang Hypertension Institute, Urumqi, Xinjiang, 830001, People’s Republic of China; 3NHC Key Laboratory of Hypertension Clinical Research, Urumqi, Xinjiang, 830001, People’s Republic of China; 4Key Laboratory of Xinjiang Uygur Autonomous Region, Urumqi, Xinjiang, 830001, People’s Republic of China; 5Hypertension Research Laboratory, Urumqi, Xinjiang, 830001, People’s Republic of China; 6Xinjiang Clinical Medical Research Center for Hypertension (Cardio-Cerebrovascular) Diseases, Urumqi, Xinjiang, 830001, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Qin Luo; Nanfang Li, Hypertension Center of People’s Hospital of Xinjiang Uygur Autonomous Region, No. 91 Tianchi Road, Urumqi, Xinjiang, 830001, People’s Republic of China, Tel/Fax +86 0991 8564816, Email luoqin2@sina.cn; lnanfang2016@sina.comBackground: Multimorbidity, defined as the coexistence of two or more chronic diseases, is highly prevalent among the elderly population and is associated with adverse outcomes. However, little is known about its relationship with sleep issues, particularly in this demographic. Therefore, this study aimed to investigate its association with sleep quality and duration among the elderly.Methods: This cross-sectional study was conducted in Emin County, Xinjiang, China, which included a population aged 60 years and above. We employed the Pittsburgh Sleep Quality Index (PSQI) score to assess sleep quality and duration. Multimorbidity was determined through self-reports, physical examination, blood tests, and imaging. Logistic regression analyses were used to explore the association between multimorbidity and sleep patterns, adjusting for confounders.Results: A total of 8205 elderly participants were included, of whom 66.8% suffered from multimorbidity. Participants with multimorbidity exhibited higher total PSQI scores [6 (3,9)], and a higher percentage of poor sleep quality (50.6%), compared to those without multimorbidity. Multimorbidity was significantly associated with the presence of poor sleep quality (OR = 1.27, 95% CI: 1.14– 1.41, P < 0.001) before and after adjusting for confounders. The risk of having poor sleep quality significantly increased as the number of multimorbidities increased. The OR (95% CI) values were 1.16 (1.02,1.32) for two diseases, 1.54 (1.26,1.90) for ≥ 5 diseases. In the adjusted model for total participants, having four diseases (OR = 1.26, 95% CI: 1.05– 1.51, p = 0.013) and five or more diseases (OR = 1.29, 95% CI: 1.03– 1.61, p = 0.029) were associated with shorter sleep duration. Furthermore, those with five or more diseases associated with longer sleep duration (OR = 1.40, 95% CI: 1.00– 1.95, p = 0.057).Conclusion: There is a significant association between multimorbidity and poor sleep quality in older community dwellers, which may provide clues for disease prevention.Keywords: multimorbidity, sleep quality, sleep duration, elderly

Ewa Ferensztajn-Rochowiak, Ute Lewitzka, Maria Chłopocka‑Woźniak et al.

Michael T. Liuzzi, Maria Kryza-Lacombe, Isaac Ray Christian et al.

Background: Irritability is a common symptom that may affect children’s brain development. This study aims to (1) characterize age-dependent and age-independent neural correlates of irritability in a sample of 4–8 year old children, and (2) examine early irritability as a predictor of change in brain connectivity over time. Methods: Typically developing children, ages 4–8 years, with varying levels of irritability were included. Resting state fMRI and parent-rated irritability (via Child Behavior Checklist; CBCL) were collected at up to three time points, resulting in a cross-sectional sample at baseline (N = 176, M = 6.27, SD = 1.49), and two subsamples consisting of children who were either 4 or 6 years old at baseline that were followed longitudinally for two additional timepoints, one- and two-years post-baseline. That is, a “younger” cohort (age 4 at baseline, n = 34, M age = 4.44, SD = 0.25) and an “older” cohort (age 6 at baseline, n = 29, M age = 6.50, SD = 0.30). Across our exploratory analyses, we examined how irritability related to seed-based intrinsic connectivity via whole-brain connectivity ANCOVAs using the left and right amygdala, and left and right ventral striatum as seed regions. Results: Cross-sectionally, higher levels of irritability were associated with greater amygdala connectivity with the posterior cingulate, controlling for child age. No age-dependent effects were observed in the cross-sectional analyses. Longitudinal analyses in the younger cohort revealed that early higher vs. lower levels of irritability, controlling for later irritability, were associated with decreases in amygdala and ventral striatum connectivity with multiple frontal and parietal regions over time. There were no significant findings in the older cohort. Conclusions: Findings suggest that irritability is related to altered neural connectivity during rest regardless of age in early to middle childhood and that early childhood irritability may be linked to altered changes in neural connectivity over time. Understanding how childhood irritability interacts with neural processes can inform pathophysiological models of pediatric irritability and the development of targeted mechanistic interventions.

Iris Tang, Serge Marbacher

J.L. Vega, A. Carrasco, N. Karim et al.

We report a 60-year-old woman who presented to the emergency department after experiencing a witnessed unknown onset bilateral tonic clonic seizure (GTCS) that culminated in cardiac arrest. A neurology consultant uncovered a years-long history of frequent episodic staring followed by confusion and expressive aphasia, which strongly suggested that she suffered from epilepsy. Thus, her cardiac arrest and subsequent resuscitation met criteria for a near-sudden unexpected death in epilepsy (SUDEP) diagnosis. Serial bloodwork demonstrated transient troponin I elevations and leukocytoses, while a brain MRI revealed global cerebral anoxic injury and a small acute right cerebellar ischemic infarction. A review of her medical record uncovered a hospitalization sixteen months earlier for a likely GTCS whose workup showed similar troponin I elevations and leukocytoses, and surprisingly, a different small acute right cerebellar ischemic infarction in the same vascular territory. To our knowledge, this is the first report of subcortical ischemic infarctions occurring concurrently with GTCSs in a near-SUDEP patient. Aside from illustrating the key role of inpatient neurologists in the diagnosis of near-SUDEP, this manuscript discusses the potential significance of postictal ischemic infarctions, transient asymptomatic troponin elevations, and transient non-infectious leukocytoses in epilepsy patients with cardiovascular risk factors.

Eleanor Huizeling, Sophie Arana, Peter Hagoort et al.

Nikhilesh Natraj, Anne Richards

Sleep spindles are a signature feature of non-REM (NREM) sleep, with demonstrated relationships to sleep maintenance and learning and memory. Because PTSD is characterized by disturbances in sleep maintenance and in stress learning and memory, there is now a growing interest in examining the role of sleep spindles in the neurobiology of PTSD. This review provides an overview of methods for measuring and detecting sleep spindles as they pertain to human PTSD and stress research, presents a critical review of early findings examining sleep spindles in PTSD and stress neurobiology, and proposes several directions for future research. In doing so, this review underscores the extensive heterogeneity in sleep spindle measurement and detection methods, the wide range of spindle features that may be and have been examined, the many persisting unknowns about the clinical and functional relevance of those features, and the problems considering PTSD as a homogeneous group in between-group comparisons. This review also highlights the progress that has been made in this field and underscores the strong rationale for ongoing work in this area.

Vickie Zhang, Michael Zhao, and Maria Dimakopoulou et al.

Surrogate index approaches have recently become a popular method of estimating longer-term impact from shorter-term outcomes. In this paper, we leverage 1098 test arms from 200 A/B tests at Netflix to empirically investigate to what degree would decisions made using a surrogate index utilizing 14 days of data would align with those made using direct measurement of day 63 treatment effects. Focusing specifically on linear "auto-surrogate" models that utilize the shorter-term observations of the long-term outcome of interest, we find that the statistical inferences that we would draw from using the surrogate index are ~95% consistent with those from directly measuring the long-term treatment effect. Moreover, when we restrict ourselves to the set of tests that would be "launched" (i.e. positive and statistically significant) based on the 63-day directly measured treatment effects, we find that relying instead on the surrogate index achieves 79% and 65% recall.

Jiaojiao Liu, Hongtao Liang, Jinfu Li et al.

The growing trend towards engineering interfacial complexion (or phase) transitions has been seen in the grain boundary and solid surface systems.Meanwhile, little attention has been paid to the chemically heterogeneous solid/liquid interfaces. In this work, novel in-plane multi-interfacial states coexist within the Cu(111)/Pb(l) interface at a temperature just above the Pb freezing point is uncovered using atomistic simulations.Four monolayer interfacial states, i.e., two CuPb alloy liquids and two pre-freezing Pb solids, are observed coexisting within two interfacial layers sandwiched between the bulk solid Cu and bulk liquid Pb. Through computing the spatial variations of various properties along the direction normal to the in-plane solid-liquid boundary lines for both interfacial layers, a rich and varied picture depicting the inhomogeneity and anisotropy in the mechanical, thermodynamical, and dynamical properties is presented. The bulk values extracted from the in-plane profiles suggest that each interfacial state examined has distinct equilibrium values from each other and significantly deviates from those of the bulk solid and liquid phases, and indicate that the complexion (or phase) diagrams for the Cu(111)/Pb(l) interface bears a resemblance to that of the eutectic binary alloy systems, instead of the monotectic phase diagram for the bulk CuPb alloy. The reported data could support the development of interfacial complexion (or phase) diagrams and interfacial phase rules and provide a new guide for regulating heterogeneous nucleation and wetting processes.

Evidence-Based Complementary and Alternative Medicine

[This retracts the article DOI: 10.1155/2022/1708769.].

Julia E. Chafkin, Joseph M. O’Brien, Fortunato N. Medrano et al.

The two studies presented in this paper seek to resolve mixed findings in research linking activity of pubertal hormones to daily adolescent outcomes. In study 1 we used a series of Confirmatory Factor Analyses to compare the fit of one and two-factor models of seven steroid hormones (n = 994 participants, 8084 samples) of the HPA and HPG axes, using data from a field study (https://www.icpsr.umich.edu/web/ICPSR/studies/38180) collected over ten consecutive weekdays in a representative sample of teens starting high school. In study 2, we fit a Bayesian model to our large dataset to explore how hormone activity was related to outcomes that have been demonstrated to be linked to mental health and wellbeing (self-reports of daily affect and stress coping). Results reveal, first that a two-factor solution of adolescent hormones showed good fit to our data, and second, that HPG activity, rather than the more often examined HPA activity, was associated with improved daily affect ratios and stress coping. These findings suggest that field research, when it is combined with powerful statistical techniques, may help to improve our understanding of the relationship between adolescent hormones and daily measures of well-being.