Exploring the Impact of Nonlinear Dynamical Neurofeedback on Post-Cancer Cognitive Impairment and Cancer-Related Fatigue: Results of Interviews with Breast Cancer Survivors

Abstract

Background:

Breast cancer survivors may experience persistent cognitive impairment and fatigue after completion of cancer treatment, which negatively impacts their quality of life. Neurofeedback is a novel, non-invasive form of brain training reported to help with symptoms such as pain, fatigue, depression, anxiety, sleep problems, and cognitive decline; however, there is a lack of research exploring its use with cancer survivors.

Objective:

The objective of this study was to describe experiences of neurofeedback and its impact on the lives of post-treatment breast cancer survivors.

Methods:

This article describes the qualitative phase of a prospective pilot feasibility trial of a nonlinear dynamical neurofeedback intervention. Study participants had the option to participate in a semi-structured interview at follow-up. A sample of 12 breast cancer survivor clients participated in interviews 5–10 weeks after the completion of 20 sessions of nonlinear dynamic neurofeedback. This qualitative descriptive study employed thematic analysis of interview transcripts.

Results:

Qualitative analysis revealed two overarching themes of impact and experience and six subthemes: symptom impact, dramatic effect, symptom improvement, enjoyable experience, lack of side effects, and recommend for cancer survivors.

Conclusion:

Results of this qualitative descriptive study suggest that nonlinear dynamical neurofeedback had a dramatic and meaningful positive effect on persistent symptoms experienced by breast cancer survivors, without any negative side effects. Participants in our sample found the neurofeedback sessions to be enjoyable and recommend that they be offered to all cancer patients. Clinical trials with larger sample sizes are needed to corroborate our findings. Establishing clinical effectiveness could encourage adoption of neurofeedback into routine cancer care and health insurance coverage.

Introduction

Cancer survivors report challenges in coping with lifestyle adjustments after their cancer diagnosis and treatment, trying to get back to their previous lifestyle, but finding they have to accept a new normal lifestyle.¹ Breast cancer survivors often experience persistent physical and psychological symptoms after completion of cancer treatment, including cognitive impairment and fatigue that negatively impact their quality of life.²

Post-cancer cognitive impairment (PCCI) is recognized as one of the most distressing symptoms in cancer survivors, generally manifesting in deficits in attention (focus), recall (memory), language (word finding), executive function (problem solving), and speed of processing; these deficits may often be subtle but have a significant negative effect on quality of life.³ Cancer-related fatigue (CRF) is a persistent physical, emotional and/or cognitive tiredness that is among the most prevalent and most distressing side effect of cancer and its treatment.^4,5 Both PCCI and CRF have historically been underreported by cancer patients and poorly managed by health care providers, as there are few evidence-based interventions to offer cancer survivors.^3,6

Existing recommendations for the management of PCCI include cognitive training and rehabilitation, exercise, and mind-body interventions.⁷ Management of CRF includes treating contributing factors, physical activity, psychosocial interventions, and consideration of psychostimulants.⁶

Neurofeedback, or electroencephalogram (EEG) biofeedback is a novel, non-invasive form of brain training reported to help with symptoms including pain, fatigue, depression, anxiety, insomnia, and cognitive decline; however, there is a lack of research exploring its use with cancer survivors.⁸ Neurofeedback is also reported to help with a variety of clinical conditions, including post-traumatic stress disorder, attention deficit hyperactivity disorder, schizophrenia, insomnia, Autistic spectrum disorder, epilepsy, depression, anxiety, and pain.^9,10 Other applications include peak performance training in athletes, executives, and students, and improvement of memory, attention, and sleep problems, with results persisting for months or years.^10–12

There are multiple diverse neurofeedback approaches and protocols. Traditional neurofeedback training aims at changing EEG amplitude and distribution patterns through principles of operant and classical conditioning to bring them closer to desired norms for specific symptoms; this linear approach requires EEG activity to reach a pre-determined criterion before feedback is delivered.^13–15 In this approach, the client must consciously attempt to control their own brainwaves by controlling the audio or video quality of a movie or playing a video game in response to their brainwave patterns.

The practitioner connects sensors to the client's scalp, which measure brain activities and transfer them to a computer program (Fig. 1). The computer software responds to the brainwave patterns with positive results when the brainwaves fall within desired limits, and it slows down or stops the video when the brainwaves extend beyond these limits. When brainwaves are too slow or too fast, an individual may feel sluggish or nervous; traditional neurofeedback aims at bringing the brainwaves into a “normal” range by “rewarding” the individual, for example, allowing them to watch a movie without interruptions.

FIG. 1.

How neurofeedback works: the biofeedback loop (photo: shutterstock_1272933439).

In contrast, nonlinear neurofeedback approaches such as NeurOptimal™ respond dynamically to each individual and their habitual brainwave patterns based on moment-by-moment calculations of antecedent EEG activity.^13,16 See Table 1 for a comparison of the characteristics of traditional linear versus nonlinear dynamical neurofeedback approaches.¹⁷ By giving auditory cues, NeurOptimal enables the individual brain to train toward its own optimal functioning by providing conscious information about emerging turbulence of the brain's electrical activity.

Table 1.

Traditional Linear Versus Nonlinear Dynamical Neurofeedback Approaches^a

Characteristic	Linear approaches	Nonlinear dynamical approaches
Focus of training	Treatment of specific symptoms or clinical problems	Restoration of brain resilience and flexibility that naturally leads to a reduction in problems and issues
Clinical diagnosis	Requires a diagnosis to design or select a training plan	No diagnosis is necessary because training helps the brain find its own best solution
Measures of cortical activity	Measures cortical activity in two ways: amplitude and frequency	Detects changes in cortical activity in four ways: activity, duration, intensity, and frequency shifts
Practitioner skill	Requires practitioner to apply or modify the training plan	Requires no additional practitioner skills as the expertise is built into the system
Side effects	Potential side effects from overtraining or selecting inappropriate training plan	No known unwanted side effects
Client effort and control	Requires effort on behalf of the client to consciously train the mind	Requires no effort on behalf of the client; client simply relaxes
Invasiveness	Invasive as training is designed to push the brain in a specific direction to achieve correction	100% non-invasive as training lets the brain “decide” which corrections work best

Adapted from NeurOptimal^® Brain Training eBook Version No 3.7 (Zengar Institute, Inc., 2022).

Feedback is provided in the form of slight interruptions in the media stream that prompt the brain to pay attention, which helps a person learn to become relaxed and/or focused by providing real-time information about how their brain is performing. This holistic form of brain training promotes self-regulation, flexibility, and resilience similar to the effects of mind-body therapies such as yoga and meditation, but results may occur more rapidly and efficiently with neurofeedback.¹⁸ Other mindfulness-based programs have demonstrated mixed effects on cognition that may be related to participant motivation.¹⁹

Brain training with the NeurOptimal neurofeedback system does not require any effort on the part of the participant, which may address this limitation of traditional mindfulness-based training. Another advantage of the nonlinear dynamic approach is that the practitioner is not required to diagnose a problem or design a therapeutic protocol, and the NeurOptimal system is user friendly. The nonlinear dynamical approach recognizes that the brain has the capacity to reorganize or rebalance its own brainwave patterns based on the feedback provided to optimize efficiency.¹⁶

This results in the individual feeling calmer and less reactive, with an improved mood and ability to stop negative thought patterns, able to focus easier and to fall asleep faster. These improvements translate to improved cognition and decreased fatigue, including in cancer patients.²⁰ These differences would make it more feasible to offer nonlinear neurofeedback on a larger scale in a clinical setting such as a cancer survivorship centre.

Evidence from two quantitative systematic reviews that included a total of six unique studies with cancer survivors suggests that neurofeedback is a safe, non-invasive, drug-free complementary therapy that has the potential to ameliorate symptoms such as cognitive problems, fatigue, sleep problems, pain, and depression in cancer survivors; however, further studies are needed.^15,21 Specifically, a few studies have examined the qualitative experiences of cancer survivors participating in neurofeedback training sessions. One recent qualitative study explored the experiences of neurofeedback and its impact on quality of life as perceived by a sample of neurofeedback providers (n = 12) and cancer survivor clients (n = 5); participants described neurofeedback as transformational, empowering, healing, comforting, and a way to pay it forward, while also describing challenges related to accessibility and failure of some individuals to respond to the therapy.²²

More qualitative studies are needed to understand the experience of neurofeedback for cancer survivors and its impact on their quality of life. These studies will assist cancer care and primary care providers to decide whether and when to recommend neurofeedback to cancer survivors in their practices.

Purpose

Building on our own incremental program of research exploring the effect of neurofeedback on cognition and fatigue, we added a qualitative component to our most recent pilot feasibility study to better understand the impact of NeurOptimal neurofeedback on symptoms and quality of life in a sample of breast cancer survivors experiencing PCCI and CRF.

Methods

Design and participants

This article describes the qualitative phase of a prospective pilot feasibility trial of a nonlinear dynamic neurofeedback intervention.²⁰ This phase employed a qualitative descriptive research approach. Study participants had the option to participate in a qualitative interview at follow-up. Of the 16 study participants, 12 (75%) opted to participate in a qualitative interview at follow-up (5–10 weeks post-neurofeedback). Post-treatment breast cancer survivors with cognitive problems were recruited through newspaper notices, and posters/postcards in community/health care settings including the regional cancer clinic.²⁰

Individuals were considered for this study if they had completed primary cancer treatment (surgery, chemotherapy, and/or radiation treatment) for earlier stage (I–III) cancers and self-reported a moderate to severe level of cognitive impairment (score or 4 or higher on a 10-point scale) and/or CRF. Individuals with advanced cancer or metastases, epilepsy, or dementia (based on self-report) were excluded.

Intervention

This pilot feasibility study used a 10-week wait-list design. Participants served as their own controls and received 20 sessions of NeurOptimal^® Version 2.0 neurofeedback delivered over a 10-week period. During each session, the participant is seated in a comfortable reclining chair. The practitioner attaches two sensors to the scalp and three to the ears. The participant listens to music throughout the 33-min session and hears a “static” sound whenever feedback is provided. Outcomes were assessed using validated, self-report scales and neuropsychological tests before, during, and after neurofeedback. The neurofeedback protocol was feasible and resulted in significant decreases in perceived cognitive deficits (FACT-Cognition), fatigue (FACT-Fatigue), sleep (PSQI), and psychological symptoms (BSI-18). Quantitative results were previously published elsewhere.²⁰

Data collection and analysis

Ethical approval was received from the Queen's University Health Sciences and Affiliated Teaching Hospitals Research Ethics Board. Semi-structured interviews were guided by an interview guide outlining key questions and potential prompts (See Table 2). Consenting participants completed a 30–60-min interview conducted by the primary author. Interviews were transcribed verbatim and verified by the second author. Data analysis was guided by the phases of thematic analysis described by Braun and Clarke.²³

Table 2.

Interview Questions and Potential Probes/Prompts

Interview questions
1. Tell me about what your life was like before your diagnosis of cancer. Describe your roles and activities that you enjoyed participating in before your diagnosis of cancer.
2. Tell me about your health before your diagnosis of cancer. Describe any chronic health problems and/or symptoms that you experienced on a regular basis.
3. Tell me about how your life may have changed with your diagnosis of cancer. Describe how your roles and activities changed as a result of your cancer diagnosis and treatment.
4. Tell me about your health after you completed your cancer treatment. Describe any health problems and/or symptoms that persisted after treatment.
5. Tell me about how and why you chose to seek neurofeedback training.
6. Tell me about your experience during neurofeedback training.
7. Tell me about what your life is like now, after completing neurofeedback training. Describe your current roles and activities that you enjoy participating in.
8. Tell me about your health after you completed neurofeedback training. Describe any health problems and/or symptoms that persist.
9. What was the impact of neurofeedback training on your quality of life?
10. What was the impact of neurofeedback training on your symptoms?
11. How satisfied were you with your experience with neurofeedback training?
12. Describe any negative side effects, if any, that you may have experienced during neurofeedback.
13. Describe how your neurofeedback trainer handled these negative side effects.
14. Describe whether you needed to seek medical care for any side effects.
15. Tell me what recommendations you would have for other cancer survivors considering neurofeedback training to help with their long-term symptoms.
Potential probes/prompts
1. Can you tell me a bit more about …?
2. Can you give me an example?
3. You mentioned … what did that mean for you?
4. Why was that important to you?

Trustworthiness in the data analysis was ensured by having two researchers independently conduct the data coding and participate in peer review of findings. Similar codes were combined to create subthemes using emerging, process, and theoretical coding, and subthemes were regrouped to generate analytic themes that were discussed to create the final set of themes.

Results

The sample consisted of 12 female breast cancer survivors diagnosed within 6 years before study enrollment. Participant ages ranged from 45 to 75 years with an average of 56 years, and all reported completing postsecondary education. At baseline, symptom severity for cognitive problems was rated from 4 to 7 out of 10 with an average score of 5.5 (standard deviation [SD] = 1.5). Fatigue at baseline was rated from 2 to 8 with an average score of 4.5 (SD = 2.2). See Table 3 for further details related to participant characteristics.

Table 3.

Participant Characteristics (n = 12)

Characteristic	n (%)	Mean (SD)	Range
Age (years)		56.3 (9.1)	45–75
Marital status
Married/common-law	8 (66.7)
Single/divorced/separated/widowed	4 (33.3)
Highest educational attainment
High school	0 (0)
College/undergraduate university	8 (66.7)
Graduate degree	4 (33.3)
Annual family income
<$50,000	2 (16.7)
$51,000–$100,000	4 (33.3)
$101,000–$150,000	3 (25.0)
>$150,000	3 (25.0)
Cancer stage
Stage 1	2 (16.7)
Stage 2	7 (58.3)
Stage 3	5 (41.7)
Time since diagnosis (years)		3.6 (2.0)	1–6
Treatments
Surgery	12 (100)
Chemotherapy	11 (91.7)
Radiation therapy	10 (83.3)
Endocrine therapy	7 (58.3)
Targeted therapy	2 (16.7)
Time since treatment end (years)		3 (1.9)	2–5
Comorbidities
Lung problems	2 (16.7)
Heart problems	2 (16.7)
Neurological problems	1 (8.3)
Mental health problems	5 (41.7)
Number of medications		4.0 (2.9)	0–8
Symptom severity at baseline (0–10)
Cognitive problems		5.5 (1.5)	4–7
Fatigue		4.5 (2.2)	2–8
Drowsiness		3.8 (3.1)	1–9
Pain		0.7 (0.7)	0–2
Anxiety		2.6 (2.5)	0–8
Depressive symptoms		1.42 (2.1)	0–7

SD, standard deviation.

All participants had finished the 20 session NeurOptimal 2.0 neurofeedback study protocol 5–10 weeks before completing an interview. Through qualitative data analysis we were able to identify two overarching themes, impact and experience, and six subthemes as described next. See Table 4 for a summary of themes and sample quotes.

Table 4.

Summary of Interview Themes

Themes	Sub-themes	Sample quotes
Impact	Symptom impact	BCS2: My brain wasn't working good…concentration. It's really hard for me to read books now, really hard. I'm easily distractableBCS3: The kind of work I do I need a lot of concentration, So, that was for me the worst side effect of the illness and treatment…the lack of concentration…Because it affected my daily work so greatlyBCS6: You know I would go home and literally, couldn't hardly do anything right and I had to be in bed by eight PMBCS8: The reason I didn't come back to work sooner was mostly because of fatigue, and problems with cognition. So, I delayed my return to work and then did a gradual return. It was very difficult…the fatigue was more cognitive fatigue, it's not a physical fatigue.BCS9: Brain fog, memory loss…five years after treatment…I was experiencing more significant memory loss, and disorientation. My ability to grasp and retain information was much less.BCS11: Emotionally, I felt traumatized. But I noticed there was a bit of a fog, a haze after chemo. I couldn't focus as well. I couldn't focus on conversations or just reading. I noticed that for sure. It's lasted for four years.BCS12: I haven't been able to return to work…I lost my accreditation because I was off so long, and to start over again, I don't have the brain capacity. I'm on long-term disability.
	Dramatic effect	BCS1: But I was starting it…and it worked, something worked within a week…something kicked in quickly… I got significantly better fast.BCS3: Okay, I'm going to say the first 3–4 treatments I didn't feel anything…but after the fourth treatment there was a drastic change, I felt like so energetic. I had so much focus. I concentrated a lot better. Honestly, it was, day and night, it was just. A big improvement!BCS3: Oh my god it was, honestly, I had a big smile on my face for two weeks. It felt so good. Yeah…I would give it 10/10! It's, it's honestly magical. Not what I expected.BCS3: It's worth it so much, it's been, uh, I, uh, anyway I'm only going to speak for myself but it made a big, big difference in my life.BCS8: I think that I can focus a little better at work… I don't feel like I am forgetting as much as I used to…I mean it's pretty amazing.BCS8: I definitely was skeptical about it but I just, I feel so much better. I can go out more in the evenings now, which is nice.BCS11: By the 5th treatment I definitely felt something. Before I was hitting this wall during the day, where I was so tired, but I noticed that really changed, that I had a lot more energy. I was sleeping a lot better. I felt able to organize my thoughts in my mind.”
	Symptom improvement	BCS2: I don't have the need to sleep in the afternoon. I don't have that level of tiredness anymore.BCS3: After four treatments I started sleeping so well…that was a big improvement for me.BCS5: My sleep has improved. That was the one thing that I did notice that it did help with.BCS7: I felt a little less anxious and it just seemed that my thought process was more clear, and concise, you know instead of the wandering, and questioning, everything seemed to be more clear.BCS8: At first, I didn't, but by the end I definitely noticed that I have more energy.BCS8: Less fatigue. I don't know if I'm sleeping better but I feel more rested when I wake upBCS8: I think that I can focus a little better at work… I don't feel like I am forgetting as much as I used to…I mean it's pretty amazing.BCS9: Uhm, yeah, I'd say, if you asked me was my energy level better after the program than before I'd say yes, absolutely.BCS10: Uhm, a great affect…when I went for the sessions I fell asleep every single time…it didn't seem to affect my brain fog at all…but It caused me to feel a little bit better because I wasn't sleep deprived.BCS 11: The anxiety was less, when it came to worrying about what I didn't get done or worrying about cancer stuff…I felt calmer again.BCS 12: Since I've done the brain thing my sleep has improved
Experience	Enjoyable experience	BCS1: It was completely pleasant…I have to say I enjoyed it.BCS2: It's relaxing you go in there They were totally relaxing you know, and you came out as if you've been in a spa or something.BCS6: It was really good. I really enjoyed itBCS7: I think it was a positive experience for sure.BCS8: I definitely was a little skeptical at the beginning…but after a couple of weeks I looked forward to going and I really enjoyed it. So I was sort of sad when it finished…It was a good experience… I would say very satisfied and surprisingly soBCS9: I was really glad to have the opportunity to do the sessions…I felt cared for in a way, you know…I guess, a calming…an ability to think of things I'm dealing with and work through them.BCS10: Uhm, I enjoyed doing it. I found it very relaxing obviously. I enjoyed when the person left the room, and you know I was there, and I closed my eyes and I fell asleep.BCS12: I did enjoy the sessions. I was sad when they stopped.
	Lack of side effects	BCS1: Side effects? None, none, none at all.BCS2: I would recommend it because it's not intrusive. It's not like a drug so there were no side effects for me.BCS2: The risks are really, are so much lower than the possible benefits, and that's what a lot of treatments have to look at.BCS3: So it was very encouraging to see that it could only get better, it could not get worse. So honestly it didn't take a lot for me to get convinced to do the neurofeedback after I saw the effect that it could have for my healthBCS10: There were no negative side effects.BCS11: No, no side effects, not that I remember.BCS12: For a day and a half after each one I seemed to be a little worse with short term memory and concentration…but I went back to what I was before I started.
	Recommend for cancer survivors	BCS1: I'd suggest people try it…it might help. It's a very effective way of spending forty-five minutes.BCS2: So I would recommend that to anybody who's had cancer because what's the harm.BCS3: I would have started it right after treatment if I had knownBCS3: I wish I had known before because I wouldn't have waited 3 years to do it.BCS6: I would say you know if you have an opportunity to uh, to do this, then I would recommend that they do this cause even if it gives you 5%, 10% more than what you are currently living with, I think it's worth it.BCS7: I think it's a good idea for them [cancer survivors] to definitely try it, and sooner than I did…when you're dealing with everything involved with being a cancer survivor that would have been helpful. Like about a year ago I think I would've really appreciated it.BCS9: I would recommend it to anybody who is a cancer survivor, absolutely… this kind of treatment really should be available on an ongoing basis to people such as myself.BCS11: I was satisfied, and I would recommend it to other cancer survivors for sure. It was a really good experience, and you never know I might be back.

Theme 1: impact

We identified three subthemes related to the impact of cancer and neurofeedback. The first subtheme, symptom impact , illustrates the debilitating consequences of cancer and cancer treatment on the lives of breast cancer survivors. Specifically, our study participants described how lingering cognitive impairment and fatigue interfered with their daily activities, “it's really hard for me to read books now” (BCS2), and return to work, “I didn't come back to work sooner was mostly because of fatigue, and problems with cognition” (BCS8)

The second subtheme related to impact, dramatic effect , captures the sudden shift in energy experienced by most participants, “Something kicked in quickly…I got significantly better fast” (BCS1), and “after the fourth treatment there was a drastic change, I felt so energetic. I had so much focus. I concentrated a lot better. Honestly, it was day and night. It was just a big improvement” (BCS3).

The third subtheme, symptom improvement , highlights the range of symptoms that were positively impacted by the neurofeedback sessions such as fatigue, sleep problems, anxiety, memory problems, and lack of focus, “I felt a little less anxious, and it just seemed that my thought process was more clear and concise you know instead of wandering and questioning” (BCS7), “my sleep has improved” (BCS5), and “I think that I can focus a little better at work… I don't feel like I am forgetting as much as I used to…I mean it's pretty amazing”(BCS8).

Theme 2: experience

We identified three subthemes related to the experience of neurofeedback training with the NeurOptimal 2.0 system. Most participants described their neurofeedback sessions as an enjoyable experience . They used descriptors such as “pleasant” (BCS1), “relaxing” (BCS2), “positive” (BCS7), and “calming” (BCS9). One participant compared it with “as if you've been in a spa” (BCS2), and another disclosed that they “felt cared for in a way” (BCS9). Others reported they were sad when the neurofeedback training ended.

The second theme related to experience was lack of side effects . None of the participants reported any new symptoms or lasting side effects as a result of the neurofeedback training, and most commented on this in some way, “side effects? none, none, none at all” (BCS1), and “it's not a drug so there were no side effects for me” (BCS2). A single participant reported a transient side effect that consisted of worsening of her existing symptoms, “for a day and a half after each one I seemed to be a little worse with short term memory and concentration…but I went back to what I was before I started”(BCS12).

The final theme identified was recommend for cancer survivors . Participants overwhelmingly indicated they would recommend neurofeedback to “anybody who's had cancer” (BCS2) and suggested the therapy “should be available on an ongoing basis to people such as myself” (BCS9). Participants also expressed regret that they didn't learn about neurofeedback sooner, “I would have started it right after treatment if I had known” (BCS3) and “I wish I would have known before because I wouldn't have waited 3 years to do it” (BCS3).

Discussion

The results of this qualitative study provide further insights into the impact and experiences of breast cancer survivors using dynamical neurofeedback to manage persistent symptoms of cancer treatment.

Impact of neurofeedback

Three subthemes were identified related to the impact of neurofeedback: symptom impact, dramatic effect, and symptom improvement. These results also support our quantitative findings, which are reported elsewhere, that demonstrated that a 20-session neurofeedback protocol delivered over 10 weeks was feasible and acceptable, and this resulted in significant decreases in participant perceived cognitive deficits, fatigue, sleep problems, and psychological symptoms. Our qualitative findings illustrate the debilitating symptoms that participants were continuing to experience years after their treatment ended and the impact it had on their lives, particularly challenges related to returning to work.

Following the neurofeedback protocol, most participants described a dramatic shift in their symptom experience, including renewed energy and concentration. This theme was previously reported in a qualitative study exploring both neurofeedback provider and their cancer survivor client experiences with neurofeedback, in which the impact was described as “transforming lives.”²²

Some participants reported a reduction in their anxiety, including worrying about the cancer. This is an interesting finding as fear of cancer recurrence is a significant, unmet psychological need for cancer survivors even 10 years after cancer diagnosis.^24,25 This would be an important variable to evaluate in future studies of neurofeedback for cancer survivors, as studies of psychological interventions have yielded only small effect sizes.²⁵

In addition, the presence of other late or long-term effects related to cancer treatment may contribute to anxiety and fear of cancer.²⁶ Thus, managing fatigue and cognitive issues through neurofeedback may indirectly improve this issue.

Recent studies have also demonstrated positive results for other symptoms experience by cancer survivors such as chemotherapy-induced peripheral neuropathy.^27,28

Experience of neurofeedback

Three subthemes were identified related to the experience of neurofeedback: enjoyable experience, lack of side effects, and recommend for cancer survivors. In addition to their positive symptom experiences, participants were overwhelming in their support of neurofeedback for other cancer survivors given their own relaxing experiences of the therapy, and the lack of negative side effects. Participants in a previous interview study similarly described their neurofeedback sessions as a “comforting experience,” and while recommending the therapy for other cancer survivors also commented on the lack of accessibility due to lack of awareness and costs that were not covered by health insurance.²²

Although the use of neurofeedback for a number of clinical conditions has grown worldwide, the therapy has not achieved acceptance by the traditional medical community due to lack of rigorous scientific research demonstrating effectiveness.²⁹ Thus, further well-designed studies are needed to build the evidence base for use of neurofeedback and specifically dynamical neurofeedback for cancer survivors experiencing persistent symptoms such as PCCI and fatigue. Recommendations to improve the rigor and replicability of applied neurofeedback research include reporting a priori sample size calculations and data collection stop rules, standardization of research practices and reporting, and preregistration of study protocols.³⁰

Conclusion

Results of this qualitative study suggest that dynamic neurofeedback had a dramatic and meaningful positive effect on persistent symptoms experienced by breast cancer survivors, without any negative side effects. Participants in our sample found the neurofeedback sessions to be enjoyable and recommend that they be offered to all cancer patients. These results will be of interest to cancer care and primary care providers seeking safe and effective interventions to address persistent symptoms in their cancer survivor patients such as PCCI. Clinical trials with larger sample sizes are needed to corroborate our findings. Establishing clinical effectiveness could encourage adoption of neurofeedback into routine cancer care and health insurance coverage.

Footnotes

Acknowledgment

Neurofeedback provided by: Linda Beckett, MD, Kingston Institute of Psychotherapy and Neurofeedback, Kingston, ON, Canada.

Authors' Contributions

M.L.-F.: conceptualization (equal); formal analysis (equal), funding acquisition (lead), and investigation (lead); writing-original draft (lead); writing-review and editing (equal). J.T.: conceptualization (equal); formal analysis (equal), writing-review, and editing (equal).

Author Disclosure Statement

No competing financial interests exist.

Funding Information

IN-CAM Canadian CAM Research Fund (CCRF) (TRAQ#6016921). Queen's University School of Nursing Research Development Fund (RDF) (TRAQ#6017393).

Abbreviations Used

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