Long-Term Effects of Neurofeedback and Hyperbaric Oxygen Therapy on Traumatic Brain Injury: A Principal Component Analysis (PCA)-Based Secondary Analysis

Severe traumatic brain injury (TBI) poses significant public health challenges, but treatments like neurofeedback and hyperbaric oxygen therapy (HBOT) show promise in aiding recovery. Neurofeedback enhances brain healing through operant conditioning, while HBOT increases cerebral oxygenation, supporting cognitive recovery. A 33-year-old woman, after suffering a severe TBI in 2018 and a long rehabilitation, began HBOT and neurofeedback in late 2021. By early 2022, she demonstrated significant cognitive, emotional, and social improvements. After numerous sessions, a June 2024 quantitative electroencephalogram (qEEG) revealed substantial brain recovery, with marked gains (Peterson et al.'s initial study) in daily functioning and specific tasks. This secondary analysis conducted in November 2024 used principal component analysis (PCA) on the initial pretest, posttest, and difference score data from the treatment period to explore the neurophysiological effects of the combined therapies. The results showed notable factor structure differences in brainwave patterns and electrode activity from the pretest to the posttest. The simpler structure observed in pretests evolved into a more complex factor structure with posttest and difference scores, indicating neurophysiological adaptations due to the interventions. This study's PCA findings align with the post-treatment qEEG statistical results conducted in June 2024 (Peterson et al.'s initial study), which identified moderate to large improvement effect sizes in the patient's brain's average frequency band parameters (g = 0.612) and small to moderate effect sizes on 19 electrode placement outcomes (uV² g = 0.339 and Hz g = 0.333). The June 2024 results indicated significant progress over a 31-month treatment period. In June 2024, the Disability Rating Scale (DRS) and the Glasgow Outcome Scale Extended (GOSE) showed substantial improvements in cognitive abilities such as feeding, toileting, grooming, and communication skills. According to the qEEG effect sizes, as well as DRS and GOSE scores from the pretest (2021) and posttest (2024), the patient demonstrated meaningful gains in brain recovery and overall quality of life. The cognitive improvements identified in the June 2024 Wilcoxon test were further corroborated by the factor structure analysis conducted in the November 2024 PCA. This alignment between the Wilcoxon test results and the PCA findings underscores the robustness of the observed cognitive gains, providing a comprehensive validation of the patient's progress. The consistency across these distinct analytical methods highlights the significant strides made in cognitive function, reinforcing the efficacy of the treatment regimen over the observed period.