Existing literature and previous work conducted by Rance and colleagues has shown that neurofeedback of brain activity in the anterior prefrontal cortex (aPFC) improved control over contamination anxiety in a subclinical population. As such, the authors aim to develop functional MRI as a potential treatment for obsessive compulsive disorder (OCD). In this study, a randomised, double-blind clinical trial was conducted to test the use of neurofeedback in the aPFC in patients with OCD. In particular, 36 participants with primary symptoms in the fear-of-harm/checking or contamination/washing domains were recruited. Participants were asked to view symptom provocative images and attempted to up- and down- regulate activity in the aPFC during different blocks of time during training. Patients assigned to the active group received two sessions of neurofeedback training while those in the control group received yoked sham feedback. Results of the treatment were measured on the Yale-Brown Obsessive-Compulsive Symptom scale along with a measure of control over the aPFC. It was found that the active group had a significantly greater reduction of obsessive-compulsive symptoms after neurofeedback compared to the control group but no significant differences in control over the aPFC. In all, these findings suggest that aPFC neurofeedback can reduce symptoms in OCD.

A systematic literature review and meta-analysis was conducted to examine the effectiveness of neurofeedback treatment for people with obsessive compulsive disorder (OCD). The authors investigated nine controlled studies with a total sample size of 1211 patients with OCD. The primary outcome measure was OCD symptoms based on the DSM IV and the Yale-Brown Obsessive-Compulsive Symptom scale (Y-BOCS). Analysis showed that there was a significant and important benefit of neurofeedback treatment in comparison to other treatments or control. As such, the results provide preliminary evidence that neurofeedback could be an effective treatment method for OCD. The authors suggest that there is a need for more clinical trials to compare the use of other medical, neurological, and behavioural interventions to neurofeedback. 

This article details a systematic review and meta-analysis on the use of biofeedback in psychiatric disorders including obsessive-compulsive disorder (OCD) and related disorders (RD). Specifically, this review identified ten studies involved 102 OCD participants, with three being randomised controlled trials, primarily utilising neurofeedback (one study involved thermal biofeedback). Out of the neurofeedback studies, five were chosen for meta-analysis, encompassing 89 patients, including two randomised controlled trials. Results indicated a varying overall effect size within the treatment group, but significant heterogeneity and inconsistency were observed. The methodological quality of the studies was generally low, indicating a high risk of bias. In conclusion, while a beneficial effect of neurofeedback for OCD patients was identified, critical limitations in methodology and potential reporting bias were noted. 

This paper focuses on a case series investigating the efficacy of qEEG-guided NF for individuals with OCD. The objective was to analyze the progression of OCD symptoms and evaluate the effectiveness of qEEG-guided NF training using clinical outcome measures.Thirty-six subjects resistant to conventional treatments for OCD underwent 9–84 sessions of qEEG-guided NF treatment. Each daily session, lasting 60 minutes, comprised two half-hour applications with a 30-minute rest between sessions.Of the 36 subjects who received NF training, 33 exhibited clinical improvement based on the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS). Seventeen subjects also completed the Minnesota Multiphasic Inventory (MMPI) before and after treatment, revealing significant improvements not only in OCD measures but also across all MMPI scores, indicating a general decrease. Physicians evaluated subjects using the Clinical Global Impression Scale (CGI), and 33 out of 36 were assessed as improved. Follow-up interviews conducted an average of 26 months after the study's completion with 36 subjects revealed that 19 maintained improvements in their OCD symptoms. This study presents compelling evidence for the effectiveness of NF treatment in OCD. 

This study aimed to evaluate the impact of independent component neurofeedback (NFB) on both EEG patterns and clinical symptoms in individuals with obsessive-compulsive disorder (OCD). Additionally, the research explored factors predicting treatment response and identified EEG correlates associated with clinical symptoms. In this randomized, double-blind, parallel design, 20 inpatients with OCD underwent either 25 sessions of NFB or sham feedback (SFB). The NFB specifically targeted the reduction of abnormal EEG activity in an independent component previously linked to this disorder. Resting-state EEG recordings taken before and after treatment were analyzed to assess post-treatment changes, their connections with clinical symptoms, and treatment response. Despite an overall lack of EEG changes assessed by standardized low-resolution electromagnetic tomography and normative independent component analysis, there was a significant clinical improvement in OCD patients. The pre- to post-treatment comparison of the trained component and frequency did not yield significant results; however, nominal values at the downtrained frequency were lower after treatment in the NFB group. The NFB group exhibited a significantly higher percentage reduction in compulsions compared to the SFB group (p = 0.015). Predictors of a less favorable treatment outcome included higher delta (1-6 Hz) and low alpha oscillations pre-treatment, as well as lower high beta activity. In conclusion, independent component NFB demonstrate effectiveness in reducing compulsions in OCD. 

This paper introduces a technique for training individuals to regulate activity in the orbitofrontal cortex (OFC) region associated with contamination anxiety using real-time functional magnetic resonance imaging (rt-fMRI) biofeedback. Elevated activity in this region is observed in both control subjects and individuals with obsessive-compulsive disorder (OCD), a prevalent and often debilitating psychiatric condition characterized by contamination anxiety. Abnormalities in the OFC are consistently identified in OCD, and hyperactivity in this region correlates with symptom severity, with reductions in hyperactivity linked to decreased symptom severity. Thus, mastering control over this brain area holds promise for improving obsessive-compulsive symptoms, including contamination anxiety. Recent studies demonstrate that individuals can learn to regulate the activity of specific brain areas through rt-fMRI biofeedback. This technique has shown success in targeting brain regions involved in emotion processing, inducing cognitive, emotional, or clinical changes in subjects. In all, this paper establishes that the use of rt-fMRI biofeedback could be a therapeutic intervention for OCD and calls for further research. 

EEG biofeedback training was used as an adjuvant treatment for obsessive-compulsive disorder (OCD) in 79 patients, and the results showed a significant improvement in symptoms and cognitive functioning. Weekly cognitive behavioural therapy sessions and sertraline were administered to the study group, while EEG biofeedback sessions and the same regimen were given to the control group. Before and after the eight-week study, the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and the Yale Brown Obsessive Compulsive Scale (YBOCS) were given. By the sixth week of treatment, the study group's OCD symptoms had improved more than those of the control group. To evaluate the long-term impacts of biofeedback training, more investigation is required.

In their recent article, they showed that a real-time functional magnetic resonance imaging (rt-fMRI) neurofeedback protocol can reduce contamination-related anxiety, a prominent symptom of many cases of obsessive-compulsive disorder (OCD). The activity in the regions of BA10, OFC and APC have been associated with contamination anxiety which is also related to OCD. They used brain functional connectivity as their baseline (rs-fMRI) to predict the improvements in contamination anxiety after neurofeedback training in the regions mentioned. Five individuals who had contamination-related OCD underwent this protocol and showed improved clinical symptomatology. These behavioural improvements were strongly correlated with baseline whole-brain connectivity in the OFC/BA 10. This suggests that rt-fMRI neurofeedback training can be beneficial for controlling contamination anxiety. 

This study aimed to show the effectiveness of QEEG- Guided Neurofeedback therapy in decreasing OCD symptoms. This study is a semi-experimental design. 12 patients who had OCD were selected randomly and placed into 3 situations randomly which were neurofeedback, drug therapy and waiting list. Padua Inventory that assesses both obsession and compulsion was used as a research tool. Neurofeedback training is performed 30 sessions (45 minutes 3 times a week) in ten weeks. Then, Padua Inventory is completed by these subjects, again. Drug group also completes Padua Inventory as pre-test and post-test in 10 weeks. This group is treated by SSRI medicines. In the end, this research showed that neurofeedback training is an effective method for decreasing OCD symptoms. 

‌This study focused on comparing the efficacy of cognitive-behavioural therapy (CBT) and neurofeedback on symptoms of adolescence obsessive-compulsive disorder. Over all 24 adolescents (12-18 years) who received the score >70 in Wechsler IQ test and the diagnosis of OCD according to the clinical interview by a child and adolescents psychiatrist and DSM-IV criteria were selected through available sampling method and they were divided into CBT and neurofeedback groups randomly. he participants fulfilled the Yale-Brown Scale before and after intervention (10 weekly sessions). Based on the results, both cognitive-behavioural therapy and neurofeedback have significant effects on reduction of symptoms of obsessive-compulsive disorder among adolescents but the effect of neurofeedback was more significantly compared to cognitive behavioural therapy.

The main purpose of this study was to be able to compare the effectiveness of neuro-feedback on the reduction of indicators obsessive-compulsive, and anxiety. Through purposeful sampling, they chose patients who had obsessive-compulsive disorder and anxiety. They were randomly assigned into groups in which one of them was drug therapy and the other was neuro-feedback. As the purpose of this study, the treatment group which is the neuro-feedback group was compared to the control group which only had the drug treatment. The anxiety was measured by Beck's questionnaire and the OCD was measured by MOCI which tells us the type and the scope of OCD. The treatment group received 40 minutes of neurofeedback sessions for 10 weeks, 3 times a week. Through statistical analysis, they found that the neuro-feedback affects checking, Kenndy and rinsing and does not affect the hesitant. Also, the results of neuro-feedback on OCD and anxiety indicates a reduction in anxiety symptoms in comparison with obsessive-compulsive disorder. 

‌This article mainly focuses on male students who have attention deficit hyperactivity disorder (ADHD) because obsessive-compulsive symptoms and aggression causes significant emotional and social function in those who have ADHD. With proper therapeutic methods, they are trying to see the effectiveness of neurofeedback on aggression and OCD. The method they used was quasi-experimental with pre and post-test researches. 24 students between the ages of 10 and 14 were selected by convenient sampling method and randomly assigned to experimental and control groups. The research tools they used included Connor’s ADHD rating scale, Yale-Brown Obsessive Compulsive Scale and Buss and Perry Aggression Questionnaire thorough pre-test and post-test. The neurofeedback sessions were conducted for 33 consecutive weeks in 3 half-hour sessions per week. Through statistical analysis (MANCOVA AND ANCOVA), it was found that neurofeedback treatments resulted in a significant reduction in all components of the aggression scores and OCD symptoms in students with ADHD (p<0.05). 

Neurofeedback training helps the patient learn to control their attentional system due to the plasticity of the neural circuits in the brain, and often helps to reduce the required dosage of ADHD medications. Feedback control alters its functions and maintains those changes even after neurofeedback treatment has stopped. Additional research as well as clinical experience says that other psychiatric disorders can also respond from neurofeedback training. When given an instruction to do something, feedback loops use neuromodulation in the prefrontal cortex by influencing how permeable the membrane is to different ions. The prefrontal cortex can then regulate frequency distribution of the thalamus and other sites, producing a decreasing the ratio of theta-beta waves which reduces ADD symptoms. A similar process helps OCD symptoms, and rehearsal can activate long term potentiation and result in long lasting changes

This article investigated the effect of QEEG (quantitative electroencephalogram) on two cases of people who had OCD. The first patient was a young woman who was on a number of medications for OCD, none of which were very effective. After undergoing 50 sessions of neurofeedback, she reported increased energy, reduced depressive mood, reduced OCD symptoms, and better concentration. Her Y-BOCS score (which is a well-used measure for OCD) reduced significantly, twice as much as what is usually found in OCD medication trials, and persisted even 15 months post-treatment. The second case was a young man who had both ADD/ADHD and OCD. After 44 neurofeedback sessions, he reported better sleep, increased mood and calmness, improved concentration, and reduced social anxiety, and his Y-BOCS score also decreased significantly even after 13 months post-treatment. 

This study examined if independent component neurofeedback (NFB) affected electroencephalogram (EEG) results and clinical symptoms in those with OCD. 20 participants, who were those with OCD, went through 25 sessions of either sham NFB (SFB) or regular NFB, and the EEG scans were compared before and after treatment. EEG change was not associated with NFB treatment, but those who underwent the NFB treatment did see a reduction in compulsion compared to the SFB group. Those who had higher delta and beta oscillations and lower alpha oscillations had worse treatment outcomes. The researchers concluded that NFB is useful to reduce compulsions in those with OCD. 

Two of the underlying mechanisms of OCD include cognitive attentional syndrome (CAS) and Cognitive emotion regulation strategies (CERS). CAS refers to the maladaptive form of anxiety that includes rumination and a focus on threat or negative emotion. CERS are emotional strategies that are flexible and are supposed to regulate the person’s emotions. There are both adaptive and maladaptive CERS, but in this case, people with OCD use maladaptive CERS more than adaptive CERS. The aim of this study is to compare the effects of meta-cognitive, neurofeedback, and medication therapies on the underlying mechanism of OCD. In this quasi-experimental pretest-posttest study, the participants were split into 4 groups; receiving either metacognitive therapy, neurofeedback therapy , medication therapy, or the control group. 10 out of 40 participants received EEG neurofeedback, implemented in a total of 30 sessions for 10 weeks, each lasting 45 minutes. The results of this study show that metacognitive and EEG neurofeedback therapy reduced the mean score of CAS and decreased the number of maladaptive strategies (CERS). On the contrary, this effect was much weaker in medication therapy. This shows the efficacy of neurofeedback on decreasing the effects of the underlying mechanism of OCD, which reduces the severity of OCD. 

According to research, attention bias and impaired working memory are factors that can lead to OCD. Attention bias is the differential allocation of attention to negative or threatening stimulus relative to the neutral stimulus. The aim of this study is to investigate the effectiveness of neurofeedback on attentional bias in people with OCD. This quasi-experimental pretest-posttest study separated the participants into two groups: experimental and intervention. The experimental group consisted of 10 participants who received neurofeedback training for a total of 15 sessions, each lasting 60 minutes. The intervention group consisted of 10 participants who thought they were undergoing neurofeedback training, but they were watching a video recording. Outcomes were measured by the Yale-Brown Scale and the emotional stroop test before sessions started, and another time after the 15th session. After analysis using multivariate analysis of covariance (MANCOVA), the results indicate that neurofeedback training reduces attentional bias along with reducing the symptoms of OCD.