Current Status of Neurofeedback for Post-traumatic Stress Disorder: A Systematic Review and the Possibility of Decoded Neurofeedback

Abstract

Background: Post-traumatic stress disorder (PTSD) is a neuropsychiatric affective disorder that can develop after traumatic life-events. Exposure-based therapy is currently one of the most effective treatments for PTSD. However, exposure to traumatic stimuli is so aversive that a significant number of patients drop-out of therapy during the course of treatment. Among various attempts to develop novel therapies that bypass such aversiveness, neurofeedback appears promising. With neurofeedback, patients can unconsciously self-regulate brain activity via real-time monitoring and feedback of the EEG or fMRI signals. With conventional neurofeedback methods, however, it is difficult to induce neural representation related to specific trauma because the feedback is based on the neural signals averaged within specific brain areas. To overcome this difficulty, novel neurofeedback approaches such as Decoded Neurofeedback (DecNef) might prove helpful. Instead of the average BOLD signals, DecNef allows patients to implicitly regulate multivariate voxel patterns of the BOLD signals related with feared stimuli. As such, DecNef effects are postulated to derive either from exposure or counter-conditioning, or some combination of both. Although the exact mechanism is not yet fully understood. DecNef has been successfully applied to reduce fear responses induced either by fear-conditioned or phobic stimuli among non-clinical participants. Methods: Follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a systematic review was conducted to compare DecNef effect with those of conventional EEG/fMRI-based neurofeedback on PTSD amelioration. To elucidate the possible mechanisms of DecNef on fear reduction, we mathematically modeled the effects of exposure-based and counter conditioning separately and applied it to the data obtained from past DecNef studies. Finally, we conducted DecNef on four PTSD patients. Here, we review recent advances in application of neurofeedback to PTSD treatments, including the DecNef. This review is intended to be informative for neuroscientists in general as well as practitioners planning to use neurofeedback as a therapeutic strategy for PTSD. Results: Our mathematical model suggested that exposure is the key component for DecNef effects in the past studies. Following DecNef a significant reduction of PTSD severity was observed. This effect was comparable to those reported for conventional neurofeedback approach. Conclusions: Although a much larger number of participants will be needed in future, DecNef could be a promising therapy that bypasses the unpleasantness of conscious exposure associated with conventional therapies for fear related disorders, including PTSD.

Neural Decoding of Multi-Modal Imagery Behavior Focusing on Temporal Complexity

“…As it has in the present study, investigating higher brain functions such as mental imagery might expand our physiological and pathological understanding of psychiatric disorders and facilitate the search for their biomarkers. Furthermore, neural decoding might help treat psychiatric disorders by application of its detailed results to neuromodulation methods such as neurofeedback (3)(4)(5)(6)(7)(8)(9)(10)(11)(12) and transcranial stimulation (88,89).…”

“…In recent years, neural decoding research has progressed along with the expansion of machine learning (ML). Neural decoding has also been applied for interpreting mental states (1,2) and for treating various psychiatric disorders with neurofeedback (3)(4)(5)(6)(7)(8)(9)(10)(11)(12). With the development of deep learning, decoding performance improvement is accelerating.…”

Travma Sonrası Stres Bozukluğunun Tedavisinde EEG-Dayalı Neurofeedback Yönteminin Kullanımı

“…Travma Sonrası Stres Bozukluğu (TSSB), hayatı tehdit edici travmatik olayları takiben gelişen ve kişide yoğun korku ve çaresizlik durumu ile karakterize edilen, kişiyi kuvvetten düşüren mental bir bozukluktur. DSM-5 (Amerikan Psikiyatri Birliği Ruhsal Bozuklukların Tanısal ve İstatistiksel El Kitabı'nın beşinci baskısı; The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition by the American Psychiatric Association (APA)) tanı ölçütlerine göre TSSB, travmatik olayın yeniden yaşantılanması, travma ile ilişkili uyarıdan kaçınma, duygudurum ve bilişte genel değişiklikler ve aşırı uyarılmışlık olarak ifade edilen dört semptom grubu ile tanımlanan heterojen bir hastalıktır (13,28). TSSB için travma-ilişkili uyarıya maruz bırakma ile ilgili olan maruz bırakma terapisi en yaygın kullanılan tedavi yöntemlerinden biri olmasına rağmen, bu tedavi şekli hastaya/danışana oldukça acı/üzüntü verici bir süreçtir (29).…”

“…Bu nedenle, TSSB için yeni tedavi yöntemlerinin geliştirilmesine ihtiyaç duyulmaktadır. NF, bu acıya/üzüntüye neden olmaksızın TSSB semptomlarını iyileştirmede ümit verici alternatif bir tedavi yaklaşımıdır (13). Feedback seansları boyunca tekrarlayıcı olarak indüklenen TSSB-ilişkili beyin aktivitelerinin spontan meydana gelme frekansları, bu seanslar sonrası değişebilmektedir (17,21) .…”

A framework for closed-loop neurofeedback for real-time EEG decoding

“…For example, a rapidly growing field is the use of neurofeedback for treatment of psychiatric disease. Three recent reviews [50,51,52] find evidence for regulation of brain regions related to emotional control using real-time fMRI, for instance for alleviating symptoms of depression or post-traumatic stress disorder (PTSD). These recent advances in neurofeedback underlines its potential for cognitive training in both healthy individuals and patients, especially if implemented in more accessible and adaptable modalities such as EEG.…”