Frontiers in Human Neuroscience最新文献

Introduction: The coordination and expression of cultural specific affective cues during speech production in a second language (L2) reflects pragmatic adaptation, which is a critical step toward learning and achieving broader pragmatic competence. Embodied cognition provides a framework for understanding how cognitive and emotional processes shape L2 expression.

Objective: This study examined how immersive language experience influences pragmatic adaptation through the vocal expression of affect and physiological arousal in Chinese ESL learners.

Methods: Acoustic analysis and electrodermal activity (EDA) measurements were used to assess affectively valenced word production in speakers with varying levels of immersive English experience.

Results: High-immersion speakers exhibited greater pitch, intensity, and duration variation, enhancing emotional expressivity. Low-immersion speakers showed constrained vocal patterns and significantly higher physiological arousal, likely due to increased cognitive demands and anxiety.

Discussion: These findings highlight the impact of L2 proficiency on affective language embodiment and the cognitive challenges faced by L2 learners. This study offers novel insights by considering a pictorial character-based language, broadening our understanding of emotion-language interaction. Findings have implications for second-language education, cross-cultural communication, and bilingual speech therapy.

Much is known about how the strength of contextual support from strongly constraining (SC) and weakly constraining (WC) sentences influences the online processing of expected (EXP) and unexpected (UNEXP) sentence-ending words. In the present study, we investigated the long-term mnemonic consequences associated with the processing of contextually constraint words and used event-related potentials (ERPs) to explore the memory retrieval mechanisms at work. Furthermore, we investigated false memories for expected but unpresented words. If these unpresented words remained highly accessible in memory, their false recognition as familiar would manifest in a larger early frontal old/new effect, the putative ERP correlate of episodic familiarity. Behavioral results indicated that strongly expected and highly unexpected words were more likely to be recognized, whereas memory for moderately expected words was attenuated. However, the anticipated early frontal old/new effects in these conditions did not materialize. Instead, the retrieval of highly unexpected (SC-UNEXP) words was characterized by a late parietal old/new effect, reflecting a reliance on recollection-based processes. Unexpectedly, during retrieval SC-UNEXP words also evoked a late frontal positivity, a pattern usually associated with the inhibition of unpresented expected words during encoding. This suggests that the retrieval of these words reactivated inhibitory mechanisms akin to those activated during encoding. Additionally, expected lures that were correctly identified as new elicited a broadly distributed positive slow wave, indicative of recollective processing in support of a recall-to-reject strategy. This latter effect was observed irrespective of the predictive strength of the contextual support.

Introduction: This study aimed to investigate the effects of acupuncture and moxibustion, as well as various acupoints, on human autonomic nervous system (ANS) function and physical stress. The research further to identify effective intervention strategies for stress management and health maintenance.

Methods: A Self-comparison design was conducted with healthy volunteers. Thirty-five volunteers received sequential 15-min interventions of moxibustion at ST36, acupuncture at CV12, and acupuncture at ST36, with a one-day washout period between interventions. Heart rate variability (HRV) was measured to assess autonomic function, and heart rate (HR) and the physical stress index (PSI) were measured to assess stress levels.

Results: Compared with the baseline, acupuncture at ST36 increased the high-frequency power (HF), root mean square of the successive interval difference (RMSSD), instantaneous standard deviation of the R-R interval (SD1), long-term standard deviation of the R-R intervals (SD2), total power (TP), and standard deviation of the normal-normal interval (SDNN). Acupuncture at CV12 increased RMSSD, SD1, SD2, TP and SDNN, with sustained effects for RMSSD and SD1 post-acupuncture, SD1/SD2 were increased post-acupuncture. The HRs of all three interventions decreased during the intervention, and remained sustained effects post-intervention. The PSI decreased during acupuncture and the stimulation at CV12 remained sustained effects post-acupuncture.

Conclusion: Acupuncture alleviates physical stress by regulating ANS activity, with distinct modulatory effects observed across different acupoints, indicating potential applications in stress management and health maintenance. Moxibustion demonstrates marked efficacy in reducing HR.

Clinical trial registration: https://itmctr.ccebtcm.org.cn/mgt/search, ITMCTR2025001289.

Background: Mild cognitive impairment (MCI) is a critical transitional stage in dementia related disorders. In that context, dorsolateral prefrontal cortex (DLPFC), and lateral parietal cortex (LPC) are subjected to neuropathological changes in MCI. Furthermore, alterations in parietal memory network (PMN) integrity and default mode network (DMN) also occur in MCI. Transcranial direct current stimulation (tDCS) is a promising neuroprotective tool that might interfere with cognitive decline in Alzheimer's disease-MCI (aMCI) and Parkinson's disease-MCI (PD-MCI) when applied to DLPFC or LPC separately.

Methods: This is a randomized and controlled study evaluating the effectiveness of tDCS in 120 patients (60 aMCI and 60 PD-MCI). Firstly, all patients will be randomly (1:1) divided into two groups: DLPFC (30 aMCI; 30 PD-MCI) and LPC (30 aMCI, 30 PD-MCI) for tDCS stimulation. Secondly, they will classify randomly (2:1) real and sham groups for tDCS applied to once a day for 10 days over 2 weeks. The stimulation will be delivered with a 2-mA current frequency and will last 20 min. The primary outcome assessment for this study will be the change in score from baseline to the end of (14-days and 90 days follow-up) the tDCS application for the neurocognitive tests. Potential outcome parameters will be discussed in the light of current literature to contribute to the new area of personalized non-invasive brain stimulation research in neurodegenerative diseases at early stages. The results of this study are expected to shed light on the neural underpinnings and pro-cognitive outcomes of tDCS. Potential outcome parameters will be discussed in the light of current literature to contribute to the new area of personalized non-invasive brain stimulation research in neurodegenerative diseases at early stages.

Introduction: Epilepsy is diagnosed in about 1% of the world's population as a common brain disease. Timely prediction and detection of seizures can significantly improve the lives of epilepsy patients.

Methods: The study has garnered considerable attention over recent years, particularly in the context of advanced computational methods. However, current seizure detection methods still face several limitations, including high inter-patient variability, noisy and non-stationary EEG signals, and the limited generalization ability of single deep learning (DL) models. This paper presents an Ensemble of Deep Transfer Learning (EDTL) models for personalized seizure detection. The technique combines ResNet and EfficientNet methods along with a customized two-Dimensional Convolutional Neural Network (2DCNN) method for patient-specific seizure detection using EEG data. Raw data from the recordings of seizure patients is transformed into EEG signals. Personalized sliding windows are used to extract and store spectrograms for the patients. Patient-specific features are extracted from individual records. EEG signals are normalized for consistent scaling. Short Time Fourier Transform (STFT) is then applied for continuous window slicing over short time intervals. To address the limitations above, the proposed EDTL framework integrates general-purpose pre trained models with a domain-specific custom 2DCNN to capture complementary features. This design improves robustness against noise, enhances adaptability to patient-specific variability, and achieves better generalization compared to individual models. The transformed data is then passed on to train and optimize the models independently and later combined into EDTL.

Results and discussion: A comparative evaluation is performed using standard evaluation metrics on two datasets, the CHB-MIT Scalp EEG Database and Turkish Epilepsy EEG Dataset. The proposed EDTL models are evaluated against the individual models on standard performance metrics, with the EDTL achieving the highest performance of 99.23% on the AUC.

Introduction: Emotional well-being (EWB) is a multifaceted construct essential for human health, conceptualized as an umbrella term for related psychometric concepts such as psychological well-being (PWB), positive mental health, health-related quality of life, thriving, and subjective well-being (SWB). However, varying definitions have prompted calls for a consensus definition. Understanding the neural mechanisms of EWB is crucial for health and intervention efforts, yet findings remain inconsistent in both empirical studies and systematic reviews. The inconsistencies in prior systematic reviews may arise from diverse definitions, an emphasis on task-independent over task-dependent modalities, and biases introduced when statistical analyses are lacking.

Methods: To address these gaps, this study presents the first preliminary systematic review and meta-analysis of the neural correlates of EWB using a consensus definition developed in 2023 by NIH EWB Research Network, which includes five domains: goal pursuit, life satisfaction, positive affect, quality of life, and sense of meaning. Importantly, we used a hypothesis-driven approach to separately examine task-dependent (task-based fMRI; n = 14) and task-independent modalities (resting-state fMRI and structural MRI; n = 7 each), clarifying their distinct and overlapping neural contributions of EWB.

Results: The left pallidum as a key region associated with task-dependent modality, likely reflecting incentive and rewards processing, while task-independent findings implicate the right superior temporal gyrus (STG) and insula, suggesting roles in social cognition and interoceptive awareness. Across both modalities, frontoparietal regions emerge as shared substrates likely contributing to cognitive control processes central to EWB.

Conclusion: Despite limited sample sizes, this review provides a preliminary neural framework of EWB, highlighting distinct and shared contributions across modalities and lay an empirical foundation for future large-scale investigations.

Systematic review registration: https://osf.io/ymtb8/overview.

Introduction: In toe walking children, impaired maturation of neuromotor control often leads to persistent use of immature motor programs. Understanding the underlying etiology of toe walking in children with cerebral palsy (CP) and idiopathic toe walking (ITW) is crucial for advancing rehabilitation strategies. This study examined gait adaptations and H-reflex responses to varied weight-bearing conditions to determine whether children with ITW and CP exhibit distinct neuromotor control strategies compared to typically developing (TD) peers.

Methods: Eight children with CP (mean age 12.9 ± 2.1 years), eight with ITW (8.6 ± 1.9 years), and 19 TD children (10.0 ± 2.6 years) walked on a treadmill under three conditions: normal bodyweight, 30% bodyweight unloading, and 30% additional bodyweight. Linear mixed-effects models assessed spatiotemporal gait parameters, margin of stability, gait variability, and H-reflex responses.

Results: Bodyweight unloading increased single-limb support time, while reducing double-limb support time and antero-posterior margin of stability across groups (p < 0.01). ITW children exhibited increased gait variability (p < 0.01) under bodyweight unloading, while CP children showed no change. H-reflex amplitudes decreased under bodyweight unloading in TD children, while CP children exhibited hyperreflexia (p < 0.05).

Discussion: The findings of this exploratory study suggest that toe walking is associated with distinct adaptive strategies in ITW and CP children to compensate for environmental challenges. In ITW, increased variability under bodyweight unloading may reflect exploratory motor control, whereas CP children relied on stiffening strategies, marked by reduced variability and hyperreflexia, indicating limited adaptability and less efficient gait patterns. These results imply that similar biomechanical constraints evoke divergent neuromotor adaptations in ITW and CP children.

Phantom limb pain (PLP) after amputation is a multifaceted condition. Targeted muscle reinnervation (TMR) surgery coapts amputated nerves to motor nerves of regional muscles, closing the neuromuscular loop, enabling improved myoelectric prosthesis control and reducing PLP. Long-term effects of TMR and residual limb use have been observed; however, the short-term neural changes and their timeline are not understood. The purpose of this study was to examine the cortical changes shortly after TMR without a prosthesis, specifically the functional connectivity and hemispheric dominance during a motor task involving the affected limb. The case participant is a male 52 years old, with a left traumatic transradial amputation sustained 4 years earlier, scheduled for TMR surgery. Data was collected before and 2 months after TMR. Brain activity was recorded using functional near-infrared spectroscopy (fNIRS) while the participant performed a gross manual dexterity task (box and block test) using their phantom hand. Pain levels were assessed using a 10-point visual analog scale (VAS). Following TMR, the participant reported a VAS score of 0 and increased use of the amputated limb in daily activities. fNIRS analysis during the affected limb task showed a reduction in interhemispheric functional connectivity, prominently in the primary sensory cortex, where the average z-value decreased from 0.29 to 0.12 after TMR. In contrast, connectivity between the premotor and supplementary motor areas increased slightly, from 0.08 to 0.12. Overall, intrahemispheric correlations decreased, with opposite patterns observed across hemispheres. The largest changes occurred ipsilaterally: connectivity between the primary motor and sensory areas increased from 0.23 to 0.27, while contralaterally it decreased from 0.22 to 0.16. Conversely, connectivity between the primary motor and premotor areas increased contralaterally but decreased ipsilaterally. Hemispheric dominance calculated through the Laterality index (LI) shifted from bilateral (LI = 0.079) to ipsilateral (LI = 0.59), primarily driven by reduced activation in the contralateral primary motor cortex. These findings suggest that TMR alone can elicit measurable cortical changes in the early post-surgical period, alongside improvements in pain and functional limb use. They also support fNIRS as a non-invasive method for monitoring neural adaptation after TMR and enhance understanding of PLP mechanisms and recovery timelines.