The Effects of Alpha-Theta EEG Biofeedback Training on Anxiety and Stress: Novel Use of Hair Cortisol Concentration as a Biomarker
Anxiety and perceived-stress ratings fell after training, offering an encouraging preliminary signal.
Zlatkova K, Kerson C, Sherman R, Bendinskas K.
NeuroRegulation · Publication date: 2026-09-28
Added to site: 2026-10-04
DOI: 10.15540/nr.13.3.220
Published September 28, 2026, confirmed by the journal and Crossref. Added October 4, 2026.
- Modalities
- Neurofeedback, Alpha-theta training
- Clinical focus
- Anxiety, Stress, Hair cortisol
- Population
- Adults with generalized anxiety disorder
- Sample
- 12 enrolled; 11 completed; cortisol analysis excluded one outlier (n=10)
- Intervention / method
- 24 twice-weekly, 30-minute eyes-closed sessions at Pz; hair sampled one month afterward
- Comparator
- Own baseline; no control group
Clinician summary
Mean STAI fell from 45.82 to 29.91 and PSS from 23.82 to 11.55. Overall cortisol change did not meet the prespecified .01 threshold. Responder-only findings are exploratory.
How to interpret the findings
Small convenience sample, no randomization or control, unblinded crossover scoring and inconsistent reported STAI z/p values limit confidence. Selecting cortisol responders cannot establish efficacy. Detailed adverse-event reporting and sustained symptom follow-up are absent.
Equipment and disclosures
The paper identifies BrainMaster Atlantis. This does not establish disease-specific regulatory clearance.
Bendinskas is CEO of the cortisol-analysis company Stress Bioanalytics. Other authors report no relevant interests; no financial support reported.
Related evidence
Compare findings from the same clinical area, including mixed results.
- The effect of heart rate variability biofeedback training on stress and anxiety: a meta-analysis. · Positive with limitations
- The effects of swLORETA Z-score neurofeedback for patients comorbid with major depressive disorder and anxiety symptoms. · Positive with limitations
- Effects of swLORETA Z-score neurofeedback in Z-coherence of the fronto-limbic circuit in patients with major depressive disorder. · Positive with limitations
- The potential of infra-low frequency neurofeedback training in peak performance: The first double-blinded placebo-controlled longitudinal study in healthy adults. · Neutral / negative
- Regulation in acute stress experience through functional near-infrared spectroscopy neurofeedback of the prefrontal cortex. · Positive with limitations
- Modulation of neuroendocrine and autonomic responses to competitive stress by slow cortical potentials training in golfers: An exploratory randomized controlled trial. · Mixed
- Acute Psychophysiological Effects Of 4-7-8 And Nadi Shodhana Breathing: A Randomized Crossover Study. · Mixed
- Psychological and physiological changes following a mindfulness-based intervention integrating breathing training and HRV biofeedback in adults with anxiety disorders · Mixed
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