Auricular neuromodulation specificity remains debated, particularly for electrical approaches in which current spread may obscure site-specific effects. We tested whether focal mechanical auricular acupressure produces site-by-pathway differences across Hot affective interference control and Cold inhibitory braking. In a single-blind, randomized, active-controlled study, 55 young adults with elevated affective symptoms received 48-h auricular acupressure at Shenmen, Subcortex, Combined (Shenmen + Subcortex), or an active Shoulder control site. Participants completed an Emotional Flanker task indexing Hot control and an Emotional Go/No-Go task indexing Cold control. Standardized change scores were analyzed using linear mixed-effects models, with hierarchical drift diffusion modeling and signal detection theory analyses used to constrain mechanistic interpretation. A significant Group × Pathway interaction was observed (p = 0.002). In the Cold pathway, Subcortex and Combined stimulation showed greater improvement than Shenmen stimulation. In the Hot pathway, Shenmen stimulation showed greater improvement than Subcortex stimulation, whereas Hot-pathway contrasts against the active control were non-significant. Focal auricular acupressure produced pathway-selective, site-dependent profiles across Hot and Cold executive-control tasks. These findings suggest relative site-by-pathway specificity, although further studies with larger samples and optimized control conditions are needed to confirm the robustness and mechanisms of this effect.

Working memory (WM) depends on dynamic cognitive control processes that adapt to task demands. Although meditation has been associated with enhanced attentional regulation, its effects on load-dependent neural dynamics remain unclear. The present study investigated the effects of one month of OM meditation on behavioral performance and electrophysiological markers of cognitive control during a visual working memory task. Thirty-four healthy adult males were randomly assigned to either an OM meditation group (n = 18) or a non-meditative control group (n = 16). Electroencephalographic activity was recorded while participants performed visual n-back task with three load conditions (0-back, 1-back, and 2-back). Behavioral performance was analyzed using linear mixed-effects models. Event-related potentials (ERPs), including the P1, N1, N2, P3, and late slow wave components, were examined using both component-based and time-resolved analyses. Behaviorally, the meditation group demonstrated greater pre-post improvements in reaction time during the 0-back and 1-back conditions, but not during the 2-back condition. Accuracy remained high across all task conditions. Electrophysiologically, a significant Group × Time × Load interaction was observed for the N2 component, primarily driven by the 1-back condition. Time-resolved permutation testing further revealed a temporally localized N2 modulation under moderate working memory demand, with no reliable effects observed in other ERP components. These findings suggest that OM meditation selectively modulates monitoring-related cognitive control processes in a demand-dependent manner. More broadly, the results support adaptive models of cognitive control and highlight the value of time-resolved electrophysiological approaches for detecting transient neural changes associated with meditation training.

The aim of this research was to examine if biofeedback nasal breathing can augment psychological and physiological recovery following exposure to mild stress. Two studies are reported. The first study (Study 1) was a feasibility study (n = 12) to examine if six minutes of biofeedback nasal breathing is relaxing and acceptable for participants. Following positive results from Study 1, Study 2 examined if biofeedback nasal breathing can enhance recovery from mild stress. In this latter study, after six minutes of free breathing (baseline), participants (n = 37) were administered the N-Back and the Go/No-Go task, to induce stress, in that order. In between each stress task, individuals practised either biofeedback nasal breathing, or free normal breathing for six minutes in a crossover design. It was found that biofeedback nasal breathing was associated with higher ratings of serenity, lower breathing rate, and an increased subjective capacity to doze, relative to baseline free breathing and post-stress free breathing. In addition, biofeedback nasal breathing was associated with higher heart rate variability (HRV) in terms of RMSSD, relative to baseline free breathing, and higher High Frequency HRV (HF), relative to baseline free breathing, and free breathing post stress. Overall, the present findings indicate that real-time auditory feedback of nasal breathing represents a feasible and potentially efficacious approach for facilitating relaxation and supporting recovery from mild psychological stress. With continued development, such methods may offer accessible and scalable strategies for enhancing emotional well-being and fostering stress resilience across both clinical and non-clinical populations.

Heart rate variability biofeedback (HRV biofeedback) is a promising treatment for improving autonomic regulation and health outcomes. Although HRV biofeedback has demonstrated benefits in younger adults, its efficacy in older adult samples remains unclear. Given age-related declines in heart rate variability (HRV) and corresponding risk for heart disease, stress-related difficulties, and cognitive decline, HRV biofeedback could be an intervention to enhance HRV and improve emotional functioning, sleep, and cognitive performance in older adults. We conducted a randomized, sham-controlled trial wherein 53 healthy older adults were randomized to active HRV biofeedback treatment or sham. Participants completed a five-week HRV biofeedback intervention with assessments measuring HRV at rest, during stress recovery, along with measures of emotional functioning, sleep, and cognitive performance and completed pre- and post-testing along with a 5-week intervention. No significant differences were detected in resting HRV between groups. However, the HRV biofeedback group showed a significant increase in LF during recovery from an acute laboratory stressor (Paced Auditory Serial Addition Test), suggesting potential modulation of HRV during recovery, particularly in low frequency oscillatory ranges. Both HRV biofeedback and sham conditions reported improved sleep quality as well as improvements in HF, RMSSD, and SDNN HRV measures, but no significant differences were present for measures of emotional functioning or cognitive performance. High adherence rates in both conditions did not moderate HRV outcomes. Findings suggest HRV biofeedback may enhance aspects of HRV during stress recovery in older adults but there were not specific improvements in resting HRV, emotional health, or cognition.

Children with autism spectrum disorder (ASD) face difficulties in expressing and recognizing emotions resulting in meltdowns and aggressive situations which is strenuous for both parents and caretakers. A device that would help parents and caretakers to identify the onset of emotional variations would not only aid in preventing undesirable situations but also help them resort to remedial therapies. Towards that, this research work focuses on identifying the positive and negative emotional state of children with ASD using electrocardiogram (ECG) signals and artificial intelligence (AI) techniques. Training AI for emotion recognition requires ECG data to reflect the emotional state. As physiological data cannot be manipulated, emotions need to be induced in children to obtain the emotional ECG data. This research analyses two emotion elicitation protocols namely audio-visual (AV) based emotion elicitation protocol and multimodal emotion elicitation protocol to identify the protocol that can be used to better elicit emotions in children with ASD. In this work, emotional ECG data was acquired from 25 children with ASD using both the protocols. Results indicate that, the ECG data elicited using multimodal emotion elicitation protocol and AV based protocol, categorize emotions at the highest average accuracy of 85.7% and 72.2% respectively. The findings suggest that stronger emotions are elicited using multimodal approach and therefore this approach may be further explored for emotion recognition research and analysis in children with ASD.

Recently, the applied psychophysiology community has started to investigate the effectiveness of combining neurofeedback and biofeedback interventions. The training triad of beta-theta neurofeedback, heart rate variability biofeedback, and box-breathing continuous feedback can influence participants' electrophysiological activity and also help healthy individuals decrease reaction time. For this purpose, twenty-two students (6 male, 16 female) were randomly assigned to three experimental groups using block randomization. The first group (N = 7) received 10 sessions of beta-theta neurofeedback, heart rate variability biofeedback, and box-breathing continuous feedback simultaneously. The second group (N = 8) underwent 10 sessions of only box-breathing continuous feedback, while the third group (N = 7) participated in 10 sessions of beta-theta neurofeedback and heart rate variability biofeedback together. A multivariate analysis of covariance was used to compare reaction time scores among the three groups in a pretest-posttest design. Additionally, repeated measures analysis of variance assessed within-group changes in electrophysiological markers across three time points: pre-test, mid-test, and post-test. Results indicated that, compared to groups 2 and 3, the visual-recognition-reaction-time scores in experimental group 1 significantly decreased (P-value < 0.05). In addition, group 1 showed significant within-group changes (P-value < 0.05) in electroencephalography measures (beta/theta power ratio and high-beta relative power) and heart rate variability (root mean square of successive differences). We conclude that the combination of beta-theta neurofeedback, heart rate variability biofeedback, and box-breathing continuous feedback can effectively reduce reaction time through mind-body interaction at a self-aware level.

Unlike the pattern-reversal visual evoked potential, the flash visual evoked potential (FVEP) has had limited clinical use because of lower reproducibility and higher inter- and intra-individual variability. One potential explanation involves the time-locked nature of FVEP recordings, where activity such as unintentional suppression of eyes-closed alpha can lead to overlapping potentials that might obscure the FVEP-P2. The present investigation evaluated the reliability of the FVEP-P2 in young healthy controls across five sessions after applying narrow-band filtering (1-7 Hz) and additional notch filtering to remove alpha and beta activity. It was hypothesized that spectral entrainment would occur within the alpha and that correction for this entrainment would significantly improve the reliability of FVEP-P2. 27 younger, healthy participants aged 18-39 years (M = 24.48, SD = 5.26; 17 females) took part in the study, all reporting no history of photosensitivity or seizures, neurological disorders, or color deficiency. Each participant experienced five sessions of 100 strobe flashes with their eyes closed. The FVEP-P2 associated with each trial was identified using an automated algorithm. Narrow-band filtering (1-7 Hz) significantly improved FVEP-P2 latency reliability compared to the uncorrected condition. Notch filters targeting alpha and beta separately did not produce significant improvements, suggesting additive or overlapping contributions. FVEP-P2 amplitude reliability also improved with filtering, primarily because of attenuating alpha-band interference. Narrow-band and notch filtering mitigated alpha- and beta-band interference, enhancing the test-retest reliability of the FVEP-P2. These findings establish a clearer physiological basis for FVEP unreliability and demonstrate that spectral correction can elevate the FVEP-P2 to clinically acceptable reliability levels, supporting the continued clinical utility of the FVEP, particularly in patients for whom pattern-reversal stimuli are unsuitable (e.g., infants, comatose, or uncooperative individuals) and as a candidate biomarker in mild cognitive impairment and Alzheimer's disease (Arruda et al., 2020; Fix et al., 2014).

This study examined the effects of infra-low frequency neurofeedback (ILF-NF) training on sleep quality, anxiety levels, and performance under pressure in semi-skilled pistol shooters. Twenty semi-skilled right-handed pistol shooters aged 20-45 were randomly assigned to two groups of 10, ILF NF, and control. Anxiety levels were assessed using the sport competition anxiety test (SCAT) and sleep quality was measured with the Pittsburgh Sleep Quality Questionnaire. Performance under pressure was evaluated using Shooter's coordination analysis target training. Results demonstrated that ILF NF training may be an effective method for improving sleep quality, reducing anxiety levels, and enhancing performance under pressure for semi-skilled pistol shooters.

Smartphones have become an essential part of our daily lives, and prolonged use in static neck flexion posture could contribute to chronic neck pain. This study compared the effects of two different forms of biofeedback on neck pain, habitual posture adoption and muscle activity during smartphone texting. This was a randomised controlled trial with 3 groups. Group 1 involved muscle biofeedback and Group 2 postural biofeedback. Each participant used the biofeedback device for 2 hours daily for 6 weeks. Control group performed stretching exercises at home for 6 weeks. Outcome measures included neck pain score (0-10) and Neck Disability Index (NDI) scores. Muscle activity and neck postural angle during smartphone texting task were also evaluated during pre- and post-intervention. Both the postural biofeedback and muscle biofeedback groups showed significant reduction in pain and NDI scores in pre-post intervention comparisons (p<0.05), but not in control group. In smartphone texting task, bilateral cervical erector spinae muscle activity and average neck flexion angle showed a trend for greater reduction in Group 1 compared to Group 2. Control group showed no change at all in muscle activity and neck postural angle. This study demonstrated the effectiveness of both postural and muscle biofeedback training producing significant reduction in neck pain and comparable extent of change in neck flexion posture and muscle activity during smartphone texting. These results suggest that biofeedback with either device can be a useful tool for self-management of neck pain related to intensive smartphone use.

To test whether brief bedside photoplethysmography-derived heart-rate variability (PPG-HRV) provides objective information about pain, sleep, and affect in adults with chronic pain, and whether sleep moderates the pain-emotion association. We conducted a cross-sectional study of consecutive inpatients with chronic pain (duration ≥ 3 months) admitted to an orthopedics/traumatology service from March 31 to September 28, 2025. Adults (≥ 18 years; right-handed) were excluded for severe internal disease or acute trauma, major psychiatric disorders, marked cognitive impairment, or recent use of anxiolytics/hypnotics. At admission, 5-min fingertip PPG-HRV was recorded under standardized bedside conditions, with artifact correction, stationarity checking, and quality-control screening applied before analysis. Outcomes were the Brief Pain Inventory-Short Form (BPI-SF), Hamilton Depression Rating Scale (HAMD-24), Hamilton Anxiety Rating Scale (HAMA-14), and a composite "sleep problems" index computed as the mean of z-scored HAMD insomnia items and the BPI-SF sleep-interference item. Analyses included correlations, cross-validated random-forest regression incorporating logarithmically transformed HF power (lnHF), and Hayes' PROCESS Model 1 testing sleep as a moderator of the pain→emotion pathway. A total of 172 patients were enrolled (37.2% men; mean age 59.2 years). lnHF was significantly associated with HFnorm, pain, sleep disturbance, and depression, but not anxiety. Random-forest models showed the strongest predictive performance for sleep disturbance (R[2]_CV = 0.844), followed by depression (R[2]_CV = 0.696) and pain-related burden (R[2]_CV = 0.506), whereas anxiety showed limited predictive performance (R[2]_CV = 0.009). HFnorm and lnHF emerged as recurrently important predictors of pain, sleep disturbance, and depressive symptoms. In moderation analyses, pain×sleep interactions were significant for anxiety (model R[2] = 0.465; β = 0.159; ΔR[2] = 0.026; p < 0.01) and depression (model R[2] = 0.513; β = 0.252; ΔR[2] = 0.066; p < 0.001). Brief bedside PPG-HRV, particularly HF-related indices such as lnHF and HFnorm, provides auxiliary physiological information related to pain, sleep disturbance, and depressive symptoms in hospitalized adults with chronic pain. Sleep disturbance amplified the association between pain and emotional symptoms, supporting the clinical relevance of the pain-sleep-emotion pathway. HRV is not suitable for diagnosis or stand-alone decision-making, but may serve as a practical adjunctive marker for risk stratification and symptom monitoring.

Virtual reality (VR)-based relaxation interventions show promising effects, yet evidence on how self-guided interventions influence real-world physiological and subjective responses among psychiatric patients remains limited. Given the exploratory and preliminary nature of this study, we examined acute and longer-term autonomic and subjective responses to self-guided VR versus audio-guided relaxation, both during at-home relaxation sessions and across daily life (ClinicalTrials.gov: NCT05440825). In a single-blind randomized controlled trial, 53 outpatients with burnout or DSM-5 psychiatric diagnoses were assigned to VR (VRelax: n = 24) or audio-guided relaxation (n = 29). Participants engaged in their assigned method at least five times weekly for six weeks while wearing an Empatica E4 during weeks 1 and 6. Heart rate (HR), electrodermal activity (EDA), heart rate variability (HRV), movement, and subjective relaxation were assessed. Both interventions produced acute reductions in HR and phasic EDA during sessions, with comparable effects across modalities and partial attenuation over time. Physiological changes did not systematically predict subjective changes, aligning with evidence that psychological experience and autonomic responses often diverge in everyday contexts. Movement was positively associated with HR and EDA, reflecting activity-related variation. Tonic HR and EDA indices showed trait-like stability, whereas phasic EDA demonstrated state-like variability. This is the first study characterizing real-world autonomic and subjective responses to both modalities among psychiatric patients. Findings indicate that both modalities downregulate autonomic arousal in everyday settings, supporting momentary relaxation without altering trait-like physiology. Results highlight the feasibility and clinical potential of integrating personalized, ambulatory relaxation interventions into routine outpatient care.

Posttraumatic stress disorder (PTSD) may be conceptualized as a condition of autonomic nervous system (ANS) imbalance and hyperreactivity, as multiple symptoms are indicative of ANS imbalance (e.g., hypervigilance, exaggerated startle response, etc.). Several meta-analyses found hyperreactivity of the sympathetic nervous system (SNS), reduced basal parasympathetic nervous system (PNS) activity, and exaggerated PNS withdrawal. Additionally, evidence-based psychotherapies (EBPs) for PTSD do not always improve this ANS imbalance, nor the negative health consequences associated with it (i.e., hypertension). As such, providing adjunctive interventions that target this may be beneficial, such as Heart Rate Variability Biofeedback (HRVB). Yet, there is limited research on how adding Trauma Informed HRVB (T-HRVB) may affect HRV and secondary mechanisms of change, such as interoceptive awareness (i.e., awareness of one's internal responses and their use in self-regulation). The current study aimed to fill this gap by examining the effectiveness of Trauma Informed HRVB (T-HRVB) among outpatient and residential veterans engaged in PTSD programming. Thirty-seven veterans completed T-HRVB while participating in either outpatient or residential treatment. HRV and self-report measures were collected at the beginning and end of T-HRVB. Improvements in both HRV and interoceptive awareness were hypothesized and confirmed, with several HRV variables (e.g., Standard Deviation of Normal to Normal, etc.) significantly increasing, as well as interoceptive listening, trusting, and self-regulation. Thus, these findings provide initial evidence of the impact of implementing biofeedback in active treatment for PTSD. However, future studies should compare T-HRVB to other active approaches.

The phenomenon of "choking" under pressure remains a significant challenge in elite sports, where traditional psychological skills training (PST) often yields limited efficacy and transferability due to its subjective nature. This study investigated the efficacy of "Cognitive Armor," a novel neurofeedback protocol designed to enhance performance under pressure by training athletes to self-regulate neural activity associated with an optimal performance state. Forty-five elite athletes from precision-based sports were randomly assigned to one of three groups: a Neurofeedback Group (NG) receiving the Cognitive Armor protocol, an Active Control Group (ACG) receiving sham neurofeedback, and a traditional PST Group (PSTG). Over a 12-week intervention, participants underwent baseline and post-intervention assessments, including quantitative EEG (qEEG), sport-specific performance tests under normal and induced pressure conditions, and psychological questionnaires. A follow-up assessment was conducted after 3 months. Results indicated that the NG demonstrated a significantly greater ability to increase the sensorimotor rhythm (SMR)/high-beta ratio compared to both control groups (F(2, 42) = 21.34, p < .001, ηp[2] = 0.50). Crucially, the NG showed significantly smaller performance degradation under high-pressure conditions than the ACG and PSTG (F(2, 42) = 8.91, p < .01, ηp[2] = 0.30), and these gains were maintained at follow-up. These findings provide promising evidence that objective, EEG-based neurofeedback can be a superior intervention for building mental resilience and preventing performance decrements in elite athletes, offering an evidence-based tool for mental conditioning in competitive sports.

Understanding the linkage between slow paced breathing (SPB), slow cortical potentials (SCP) and the human consciousness could help to improve practicing strategies in the field of mental well-being. Providing 25 individuals performing two different breathing cycles (6 s-cycle and 10 s-cycle), which were accompanied by the sound of a humming gong, while measuring a 64-channel EEG, our study provides an insight into the relationship between SPB and SCPs. More importantly, it points out the greater impact of the 10 s-cycle on SCPs than the 6 s-cycle. Breathing with a frequency of 0.1 Hz led to an increased SCP-amplitude ratio as well as to a synchronization of SCPs with the breathing rhythm. Also, non-SCP frequencies were considered. Here, the 10 s-cycle showed the increased appearance of delta (ES_t = 3.52), theta (ES_t = 4.11), and alpha 1 (ES_t = 3.47) frequencies, especially in the occipital and central parietal regions. Moreover, subjectively, the SPB intervention has been rated to evoke an increased feeling of "integrity" and "balance" as well as a slightly increased feeling of "vitality". Demonstrating the relation between SPB, SCPs, and subjective mental feeling, this study contributes to emphasizing the importance of SPB in mental health.

This study aimed to examine the restorative effects of aerobic exercise on mental fatigue using physiological indicators. Mental fatigue was induced in healthy adults using the Paced Auditory Serial Addition Test. Of these, 40 participants who exhibited confirmed fatigue based on flicker values were randomly assigned to either an exercise group (20 min of aerobic exercise) or a rest group (20 min of bed rest); n = 20 per group. Flicker values and electroencephalographic (EEG) parameters (mean power of theta, alpha, and beta waves) were measured before and after the intervention. Fatigue recovery was assessed through within-group comparisons of pre- and post-intervention values and between-group comparisons of change scores. In the exercise group, flicker values significantly increased post-intervention, and this change was significantly greater than that in the rest group. EEG analysis revealed a significant increase in theta power post-intervention in the exercise group. Additionally, alpha and beta power increased significantly, with changes greater than those in the rest group. Conversely, no significant changes in flicker values or EEG measures were observed in the rest group. Correlation analysis revealed that the degree of recovery in flicker values was significantly and positively correlated with increases in alpha and beta wave power. Aerobic exercise produced a significantly greater restorative effect on mental fatigue than bed rest, as evidenced by objective indicators such as flicker values and EEG measures. The findings suggest that aerobic exercise is a promising intervention for addressing mental fatigue in contemporary society.Trial registration UMIN000057499, Registered 3 April 2025 (retrospectively registered).