The Effects of Alpha-Theta EEG Biofeedback Training on Anxiety and Stress: Novel Use of Hair Cortisol Concentration as a Biomarker

Authors

  • Katya Zlatkova Saybrook University
  • Cynthia Kerson Saybrook University, Pasadena, California, United States
  • Richard Sherman Saybrook University, Pasadena, California, United States
  • Kestutis Bendinskas Stress Bioanalytics, LLC, SUNY Oswego, Oswego, New York, US

DOI:

https://doi.org/10.15540/nr.13.3.220

Keywords:

alpha-theta training, hair cortisol concentration, stress biomarker, anxiety, neurofeedback

Abstract

Electroencephalographic (EEG) biofeedback is a widely used nonpharmaceutical intervention for enhancing human functioning. This pilot study examined whether 24 sessions of alpha-theta (AT) training would reduce stress, as measured by hair cortisol concentration (HCC) and subjective anxiety scales, in 11 adults with generalized anxiety disorder (GAD). Pre- and postintervention measures included the State-Trait Anxiety Inventory (STAI), the Perceived Stress Scale (PSS), and HCC from hair samples. A novel 5-point Likert scale assessed five areas of functionality. Wilcoxon signed-rank tests revealed significant decreases in STAI and PSS scores (p < .01), with large effect sizes (d = 1.174; d = 1.655). Likert responses were positive, with most improvement in resilience and emotional status. Eight participants showed decreased postintervention HCC, though overall changes for N = 10 were not statistically significant (p > .01), as they included participants who did not respond to the training. The magnitude of HCC change indicated a moderate effect size (d = 0.62). In responders, HCC reduction was significant (p = .006) and linked to higher crossover percentages, suggesting deeper AT learning may lower cortisol. This is the first study to show the potential of AT training as a nonmedication approach to anxiety and stress reduction, with HCC being a novel objective biomarker.

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Published

2026-09-28

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Zlatkova, K., Kerson , C., Sherman, R., & Bendinskas, K. (2026). The Effects of Alpha-Theta EEG Biofeedback Training on Anxiety and Stress: Novel Use of Hair Cortisol Concentration as a Biomarker . NeuroRegulation, 13(3), 220. https://doi.org/10.15540/nr.13.3.220

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Vol. 13 No. 3 (2026)

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Research Papers

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Copyright (c) 2026 Katya Zlatkova, Cynthia Kerson , Richard Sherman, Kestutis Bendinskas

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