Neurofeedback and neural self-regulation: a new perspective based on allostasis

The impact of ILF neurofeedback on inhibitory control in high-functioning adolescents with autism spectrum disorder: Preliminary evidence of a randomized controlled trial

BACKGROUND

Individuals with Autism Spectrum Disorder (ASD) often exhibit impairments in inhibitory control, which can impact their cognitive functioning. This study aimed to investigate the effectiveness of Infra-Low Frequency (ILF) neurofeedback in improving inhibitory control among high-functioning adolescents with ASD.

METHODS

A single-blind, two-armed randomized controlled trial was conducted with 24 adolescents with ASD randomly divided into two groups (active and sham; n = 12 per group). Both groups participated in 15 sessions of one-hour ILF neurofeedback, three times per week. The ILF neurofeedback protocol was applied to the active group, while the sham group received an inactive intervention. Outcomes were measured at the pretest, post-test, and follow-up stages.

RESULTS

ILF neurofeedback significantly improved inhibitory control in adolescents with ASD, as indicated by improvements in behavioral measures and absolute power analysis. The most significant differences were observed in alpha, theta, and gamma waves located in the central areas of the left gyrus. However, no significant effect was observed at the follow-up level on either behavioral measures or absolute power.

CONCLUSION

The results suggest that ILF neurofeedback is effective in improving inhibitory control in high-functioning adolescents with ASD. This non-invasive intervention has the potential to improve inhibitory control in this population. However, future research is needed to determine the long-term effects of ILF neurofeedback.

Mindfulness-Based Interventions and the Hypothalamic-Pituitary-Adrenal Axis: A Systematic Review

BACKGROUND

Numerous studies have evaluated the effect that mindfulness-based interventions (MBIs) have on multiple health outcomes. For its part, stress is a natural response to environmental disturbances and within the associated metabolic responses, alterations in cortisol levels and their measurement in different tissues are a way to determine the stress state of an individual. Therefore, it has been proposed that MBIs can modify cortisol levels.

METHODS AND RESULTS

The objective of this systematic review was to analyze and summarize the different studies that have evaluated the effect of MBIs on cortisol levels. The following databases were consulted: MEDLINE, AMED, CINAHL, Web of Science, Science Direct, PsycINFO, SocINDEX, PubMed, the Cochrane Library and Scopus. The search terms "mindfulness", "mindfulness-based interventions" and "cortisol" were used (and the search was limited to studies from January 1990 to May 2024). In order to reduce selection bias, each article was scrutinized using the JBI Critical Appraisal Checklist independently by two authors. We included those studies with specified intervention groups with at least one control group and excluded duplicate studies or those in which the intervention or control group was not adequately specified. Significant changes in cortisol following MBIs were found in 25 studies, while 10 found no changes. The small sample size, lack of randomization, blinding, and probable confounding and interaction variables stand out in these studies.

CONCLUSION

MBIs have biological plausibility as a means of explaining a positive effect on cortisol levels; however, the weakness of the studies and the absence of robust designs makes it difficult to establish a causal association between both variables.

REGISTRATION NUMBER

INPLASY2024110017.

Mapping the evolution of neurofeedback research: a bibliometric analysis of trends and future directions

Introduction

This study conducts a bibliometric analysis on neurofeedback research to assess its current state and potential future developments.

Methods

It examined 3,626 journal articles from the Web of Science (WoS) using co-citation and co-word methods.

Results

The co-citation analysis identified three major clusters: "Real-Time fMRI Neurofeedback and Self-Regulation of Brain Activity," "EEG Neurofeedback and Cognitive Performance Enhancement," and "Treatment of ADHD Using Neurofeedback." The co-word analysis highlighted four key clusters: "Neurofeedback in Mental Health Research," "Brain-Computer Interfaces for Stroke Rehabilitation," "Neurofeedback for ADHD in Youth," and "Neural Mechanisms of Emotion and Self-Regulation with Advanced Neuroimaging.

Discussion

This in-depth bibliometric study significantly enhances our understanding of the dynamic field of neurofeedback, indicating its potential in treating ADHD and improving performance. It offers non-invasive, ethical alternatives to conventional psychopharmacology and aligns with the trend toward personalized medicine, suggesting specialized solutions for mental health and rehabilitation as a growing focus in medical practice.

The Correlation Between Cognitive Flexibility and Learning Strategies Adopted by Medical Students

Background and objective The term cognitive flexibility refers to the ability of the students to adapt to a challenging environment. This quality has been found to enhance creativity and skills for innovation among medical students who are expected to face a taxing environment in clinical settings. Medical students should be competent enough to address the problems on their own and work with autonomy. The practice of self-regulated learning (SRL) can be associated with cognitive flexibility. Hence, this study aimed to determine the correlation between learning strategies and cognitive flexibility. Our primary objective was to correlate the different learning strategies adopted and cognitive flexibility among medical students. Material and methods This descriptive cross-sectional study was conducted at Sri Venkateshwaraa Medical College Hospital and Research Center, Ariyur, Pondicherry after obtaining institutional ethical committee approval. Students from the second year to the final year of the MBBS course who volunteered to participate in the study were selected based on inclusion and exclusion criteria. The Motivated Strategy for Learning Questionnaire (MSLQ), consisting of 50 items in Part B, was employed to assess SRL. Cognitive flexibility was measured using the Stroop Color and Word Test (SCWT) and Trail Making Test (TMT) Part A and Part B. Results The study included a total of 220 medical students. The mean age of the participants was 21.76 ± 1.77 years, and they had a healthy mean BMI of 21.06 ± 1.25 kg/m2. There was no significant difference in terms of gender in the tested variables. Responses in Card "C" and Card "CW" of the Stroop test showed a significant positive correlation (p<0.001) with subscales of SRL strategies. In the TMT, the latency of Trail A showed a significant negative correlation (p<0.001) with all the subscale scores of the SRL strategies, and the latency of Trail B showed a negative correlation with rehearsal (p=0.03), organization (p=0.03), and effort regulation strategies (p=0.01) of SRL. Conclusion Implementing SRL techniques can ultimately help medical students to act more wisely and judiciously. Hence, we propose that cognitive flexibility among medical students can be enhanced by adopting SRL strategies.

An investigation of the effectiveness of neurofeedback training on motor performance in healthy adults: A systematic review and meta-analysis

Neurofeedback training (NFT) refers to a training where the participants voluntarily aim to manipulate their own brain activity using the sensory feedback abstracted from their brain activity. NFT has attracted attention in the field of motor learning due to its potential as an alternative or additional training method for general physical training. In this study, a systematic review of NFT studies for motor performance improvements in healthy adults and a meta-analysis on the effectiveness of NFT were conducted. A computerized search was performed using the databases Web of Science, Scopus, PubMed, JDreamIII, and Ichushi-Web to identify relevant studies published between January 1st, 1990, and August 3rd, 2021. Thirty-three studies were identified for the qualitative synthesis and 16 randomized controlled trials (374 subjects) for the meta-analysis. The meta-analysis, including all trials found in the search, revealed significant effects of NFT for motor performance improvement examined at the timing after the last NFT session (standardized mean difference = 0.85, 95% CI [0.18-1.51]), but with the existence of publication biases and substantial heterogeneity among the trials. Subsequent meta-regression analysis demonstrated the dose-response gradient between NFTs and motor performance improvements; more than 125 min of cumulative training time may benefit for the subsequent motor performance. For each motor performance measure (e.g., speed, accuracy, and hand dexterity), the effectiveness of NFT remains inconclusive, mainly due to its small sample sizes. More empirical NFT studies for motor performance improvement may be needed to show beneficial effects on motor performance and to safely incorporate NFT into real-world scenarios.