Neural Noise- A systematic review addressed real-time fMRI neurofeedback training of the insula (“Island of Reil”) (Nature).1
- The review covers neurofeedback and self-regulation; the paradigm is fMRI-only, with no electrophysiology or BCI control loop.1 1
Weekly enrichment (2026-07-20)
- The review is “Self-navigating the ‘Island of Reil’,” published in Translational Psychiatry (Nature portfolio, 2025; DOI 10.1038/s41398-025-03382-8), synthesizing real-time fMRI (rtfMRI) neurofeedback studies that trained voluntary regulation of insula activity using the BOLD signal as the feedback source.2
- Selection followed PRISMA: a literature search on 2 April 2024 across PubMed, ScienceDirect and Web of Science returned 865 articles, plus 34 potential trial registrations from ClinicalTrials.gov (899 total); screening narrowed to 40 full-text articles and a final 25 studies.2
- Eligibility required rtfMRI-NF specifically (excluding EEG, fNIRS or electrophysiology feedback) and original research using BOLD as the NF source, confirming the paradigm is imaging-only with no BCI control loop.2
- Of the 25 studies, 21 (84%) reported successful insula self-regulation, split as 13 of 14 healthy-participant studies (92.86%) and 8 of 11 clinical studies (72.73%).2
- Participants’ average age ranged from 11.6 to 48.44 years across studies, and clinical cohorts spanned schizophrenia, disruptive behavior disorder, OCD, spider phobia, major depressive disorder, addiction, and criminal psychopathy.2
- Training success was most consistently assessed by comparing first versus last NF training runs (15 of the 21 successful studies); a meta-analysis of the 11 studies with usable statistics found a medium effect size for this improvement.2
- Brain–behavior associations were reported in only 10 studies, and regulation success was not consistently paralleled by behavioral or symptom change — the review’s central caveat that NF protocols need optimization.2
- The authors recommend well-designed control groups/conditions, a priori sample- and effect-size determination, standardized statistical reporting, and pre-registration/registered reports, which remain rare in the rtfMRI-NF field.2
- Clinical implication: because the insula is central to interoception, emotional and salience processing, the review positions rtfMRI-NF as a candidate therapeutic tool for disorders with insula dysfunction, with a documented maintenance/sustained-improvement effect; complementary work such as interoceptive “listen to your heart” heartbeat-based strategies (NeuroImage 2023) illustrates protocol refinement directions.23