Intensive-neurofeedback Protocol for Children With ADHD: A Proof-of-concept Study Comparing iAPF-personalized and Standard Theta-beta-ratio Training

The first aim of this clinical trial is to test the feasibility and signal validity of a new approach to neurofeedback training (NF) using intensive EEG-based theta-beta NF for children with ADHD in the context of NF camps during school holidays. The second aim is to compare the efficacy of two neurofeedback protocols in reducing ADHD symptoms. Previous study results highlight that children with ADHD frequently show increased Theta-Beta-Ratios (TBR) in the qEEG, probably associated with attention difficulties, which may be ameliorated following neurofeedback training. However, the current state of research shows heterogenous findings regarding the efficacy of standard TBR NF for children with ADHD. Further study results suggest that personalized NF training protocols, based on the individual alpha peak frequency (iAPF), may be more effective in reducing ADHD symptoms than standardized ones.

Therefore, in this proof-of-concept study of children with ADHD a standard TBR NF protocol is compared with an iAPF-personalized TBR NF (iAPF-TBR NF) protocol (based on the previously obtained iAPF). The study is designed as a randomized controlled intervention trial (RCT) with three assessment points (pre [T1], post [T2] and 6-month follow-up [T3]). Primary endpoints include the reduction of ADHD symptoms assessed by parent-, teacher- and self-report questionnaires. Furthermore, it is hypothesized that NF training is associated with better performance in a sustained attention and executive function test and a reduced TBR in qEEG, particularly following iAPF-TBR NF.

The main questions are:

• Is it feasible to train groups of up to 12 children with two sessions NF per day for an eight-day-period during their school holidays?
• Does iAPF-TBR NF provide a valid neuromodulatory signal compared to the standard-TBR-NF protocol? Do the frequency boundaries demonstrate spectral stability across the 16 training sessions?
• Does the personalized iAPF-TBR NF training reduce ADHD symptoms measured immediately after the training more than standard-TBR-NF training? (comparison T2-T1)
• Does the personalized iAPF-TBR NF training reduce ADHD symptoms measured 6 months after the NF training more than standard TBR-NF training? (comparison T3-T1)
• Does the reduction in ADHD symptoms measured immediately after the NF-training persist until the 6-month follow-up? Do possible differences between iAPF-TBR NF training and standard TBR NF training remain? (comparison T3-T2)

Post-hoc analyses of the courses are carried out. In addition, selectivity analyses will be carried out for clinical subgroups (e.g. different ADHD profiles)

Study Overview

• Status: Recruiting
• Conditions: ADHD; Executive Dysfunction; Hyperactivity; Impulsivity; Inattention
• Intervention / Treatment: Behavioral: iAPF -TBR-NF; Behavioral: Standard TBR-NF

Detailed Description

The study investigates the effectiveness of two NF approaches within a "school-holiday-camp"-setting. NF is a learning method based on neural plasticity, where specific EEG frequency bands are fed back in real-time. Participants will be randomly assigned to one of two conditions:

1. Standard-NF training targeting a reduction of the TBR with fixed reward frequencies for the entire group.
2. iAPF-TBR NF training targeting a reduction of the TBR with reward frequencies individually adjusted based on the child's pre-measured iAPF.

The training includes two sessions daily over eight camp days (a total of 16 sessions). While a small effect size (d = .2) would be expected for the comparison of iAPF-TBR NF and standard TBR NF requiring a total sample of N = 620 α= .05, 1-β = .8, G*Power; Faul et al., 2007), the present study is designed as a preliminary proof-of-concept study including an adopted target sample size. Therefore, the target sample size is set at N = 40 participants (n = 20 per arm). This sample size is sufficient to detect a medium to large effect (d = .7) with α= .10 and 1-β = .7 using one-tailed testing. This directional testing is justified by the theoretical advantage of personalized iAPF-TBR over the standard-TBR NF. The results of this pilot study will serve as essential preliminary evidence to justify the scaling of the protocol in a fully powered RCT.

The effects will be evaluated at the EEG, parent-, teacher- and self-report questionnaires, and behavioral (CPT) levels. The main objective is to determine whether the personalized NF protocol leads to superior and more sustainable effects.

Baseline frequency bands: Prior to each neurofeedback session, a one-minute resting-state EEG baseline is recorded to establish individual gain thresholds for theta and beta power. To control for non-cortical influences such as EMG artefacts, Power in frequency band 20-40 Hz is additionally required to be below a baseline threshold.

For NF and QEEG the THERA PRAX® MOBILE 13-channel full-band DC-EEG devices will be used (neuroConn GmbH, Ilmenau, Germany). They include a THERA PRAX® MOBILE MONITOR (PC panel) with INTEL CPU Core i3, 15" TFT color monitor and Windows® 10. The EEG amplifier is the THERA PRAX® DC-EEG Amplifier with 13 unipolar channels with an input impedance of < 10 GΩ, digitized with 24-bit-resolution and a sampling rate of 256/s. For skin preparation alcohol and abrasive gel (Nuprep Gel, D.O. Weaver, Aurora, CO), Ag/AgCl ring electrodes, covered with conductive paste (Ten20, D.O. Weaver) will be used. EEG, EOG and EMG data will be measured and stored by the THERA PRAX® system. The online processing of the measured EEG data during NF sessions uses a short-time Fourier-transformed moving average before the participants receive feedback on the monitor. As feedback, elements of a 15*15 grid picture selected by the participant were uncovered if the dynamic reward condition (with respect to Baseline B: EMGLOW ≤ B - 2.0 μV and Theta ≤ B + 3.0 μV and Beta ≥ B + 3.0 μV activity) is reached for 250 ms , respectively. The length of the time window analyzed in each case is 1 s which is shifted in steps of 40 ms.

• Study Type: Interventional
• Enrollment (Estimated): 40
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Luisa Himmelmeier, M.Sc. Psychology; Phone Number: +49 (0) 521 106 67534; Email: Lhimmelmeier@uni-bielefeld.de
• Study Contact Backup: Name: Sarah Lühr, M.Sc. Psychology; Phone Number: +49 (0) 521 106 4513; Email: sarah.luehr@uni-bielefeld.de

Study Locations

• Germany
  • Bielefeld, Germany, 33615
    • Recruiting
    • Bielefeld University
    • Contact: Luisa Himmelmeier, M.Sc. Psychology; Phone Number: +49 (0) 521 106 67534; Email: Lhimmelmeier@uni-bielefeld.de
  • Marburg, Germany
    • Recruiting
    • Philipps-University Marburg
    • Contact: Björn Albrecht, Dr.; Phone Number: +49 6421 28-24026; Email: bjoern.albrecht@staff.uni-marburg.de

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Children aged 6-13 years. Confirmed ADHD diagnosis (ICD 10: F90.0, F90.1, or F98.8)
• German-speaking children with normal or corrected vision.

Exclusion Criteria:

• Children with neurological disorders (e.g., Epilepsy)
• Children without an ADHD diagnosis
• Caregivers with inability to provide informed consent or complete questionnaires
• Participation in neurofeedback that was conducted in the year prior to the intended participation or is still ongoing.

The intake of medication or psychotherapeutic treatments and ICD-10 diagnosis are queried at T1, T2 and T3. These are recorded as control variables and are not exclusion criteria. The medication intake was kept constant during the NF training.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: iAPF-TBR-NF	Behavioral: iAPF -TBR-NF; Reward frequencies are adjusted based on the child's iAPF to create a customized training protocol: Calculation of the frequency bands using T1-iAPF (Hao et al., 2022): Frequency bands with individual division: Theta 4 - 0.8 * iAPF Hz Alpha 0.8 * iAPF - 1.3 * iAPF Hz Beta 1.3 * iAPF - 3.0 * iAPF Hz Gamma 3.0 * iAPF - 45 Hz; Upgrade individually calculated beta frequencies; Downgrade individually calculated theta frequencies; Aim: Reduce Theta-Beta Ratio; 10-20-electrode positions: Cz with reference and ground electrodes at A1 and A2; Duration: 15 min.
Active Comparator: Standard-TBR-NF	Behavioral: Standard TBR-NF; Training is based on the classic Theta-Beta-Ratio protocol, where the reward frequencies are fixed for the entire training group (Hao et al., 2022): Frequency bands with fixed division: Theta 4 - 8 Hz Alpha 8 - 13 Hz Beta 13 - 30 Hz Gamma 30 - 45 Hz; Upgrade Beta Frequencies: 13 - 30 Hz; Downgrade Theta Frequencies: 4 - 8 Hz; Aim: Reduce Theta-Beta Ratio; 10-20-electrode positions: Cz with reference and ground electrodes at A1 and A2; Duration: 15 min.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Adverse effects	Effects that lead to symptom enhancements, as well as negative side effects of the neurofeedback training, are considered as adverse effects. The absence of adverse effects is one indicator of feasibility.	Baseline at week 1, during week 5 and 6 after each neurofeedback session (intervention), post-measurement at week 10, follow-up-measurement at week 30
Drop-Out rate	The rate of participants discontinuing the neurofeedback training and study participation is measured. The drop-out rate is one indicator (acceptability) of feasibility.	Baseline at week 1, during week 5 and 6 after each neurofeedback session (intervention), post-measurement at week 10, follow-up-measurement at week 30
Number of included segments	The continuous EEG recorded during active neurofeedback training is scanned offline for artefacts, and the proportion of artefact-free segments is considered as an indicator of data quality (and thus feasibility) during neurofeedback training. Higher numbers of included segments indicate a larger amount of artifact-free data, suggesting higher data quality.	During week 5 and 6 after each neurofeedback session (intervention)
Diagnostic system for mental disorders according to ICD-10 and DSM-5 for children and adolescents - III External report form ADHD specific (DISYPS-III FBB-ADHS; Döpfner et al., 2017)	Parent- and teacher-reported total score of ADHD symptoms, inattention, hyperactivity-impulsivity. It also captures functional impairment and distress. These can be used to determine whether or not the criteria for an ADHD diagnosis are met. In the analysis of this study, the scales for the three cardinal symptoms: inattention, hyperactivity-impulsivity and the total ADHD symptom score will be focussed. The subscales consist of 9 items (inattention) and 11 items (hyperactivity-impulsivity), which are rated between the categories 0 = "not accurate at all" and 3 = "especially accurate". Point-values between 0 and 27 can be reached for inattention and between 0 and 33 for hyperactivity/impulsivity. The total ADHD score uses the 20 items of both subscales and though can reach point-values between 0 and 60. The scales' scores show an increase in severity of symptoms (inattention, hyperactivity/impulsivity and total ADHD) as the point-values increase.	Baseline at week 1, post-measurement at week 10, follow-up-measurement at week 30
Child Behavior Checklist 6-18/R (CBCL; Döpfner et al., 2014)	Parent report questionnaire for assessing attention problems, with help of the two symptom groups: inattention and impulsivity/hyperactivity. The analyses are carried out primarily with the total score of the scale. The subscale attention problems contains 10 items with answer categories ranging from 0 = "not correct" to 2 = "absolutely correct", resulting in point-values ranging from 0 to 20. Because a separate previous study with the same questionnaires showed particular predictivity in the Child Behavior Checklist with certain 7 items, the analyses are calculated again with the shortened version on inattention (point-values: 0-14). The scales' scores show an increase in severity of inattention symptoms as the point-values increase.	Baseline at week 1, post-measurement at week 10, follow-up-measurement at week 30
Teacher Report Form 6-18/R (TRF; Döpfner et al., 2014)	Teacher Report questionnaire investigating attention problems divided into inattention and hyperactivity/impulsivity. The analyses are carried out primarily with the total score of the scale. For assessing inattention, the scale uses 14 items with answer categories ranging from 0 = "not correct" to 2 = "absolutely correct", resulting in point-values ranging from 0 to 28. Hyperactivity/Impulsivity is assessed with 12 items and the same answer categories, resulting in possible point-values between 0 and 24. Because a separate previous study with the same questionnaires showed particular predictivity in TRF with certain 7 items, the analyses are calculated again with the shortened version on inattention (point-values: 0-14). The scales' scores show an increase in severity of inattention symptoms as the point-values increase.	Baseline at week 1, post-measurement at week 10, follow-up-measurement at week 30
Youth Self Report 11-18/R (YSR, Döpfner et al., 2014)	Self-report for children assessing attention problems divided into inattention and impulsivity/hyperactivity. The analyses are carried out primarily with the total score of the scale. The YSR will be used for children upon the age of 6 years, as the previous study showed usability for children under the age of 11 years. The subscale attention problems contains 9 items with answer categories ranging from 0 = "not correct" to 2 = "absolutely correct", resulting in point-values ranging from 0 to 18. Because a separate previous study with the same questionnaires showed particular predictivity in YSR with certain 7 items, the analyses are calculated again with the shortened version on inattention (point-values: 0-14). The scales' scores show an increase in severity of inattention symptoms as the point-values increase.	Baseline at week 1, post-measurement at week 10, follow-up-measurement at week 30
Change in central theta and beta activity	Quantitative EEG: 10 min. (5 min. eyes opened, 5 min. eyes closed): Measured frequency bands: theta, alpha, beta, gamma; Aimed for data analysis with the Brain Vision Analyzer software, version 2.3.0 (Brain Products GmbH, Germany): theta and beta with at least 30 segments (2s each) of the first three minutes Electrode positions: Fpz, Fz, Cz, Pz, Oz, A1 and A2, VEOG (electrodes placed above and below the left eye), HEOG (electrodes placed at the outer canthi)	Baseline at week 1, post-measurement at week 10, follow-up-measurement at week 30

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Behavior Rating Inventory of Executive Function (BRIEF; Drechsler et al., 2013)	Parent questionnaire to assess two main indices (Behavioral and Cognitive Regulation Indices), which form the Global Executive Composite Score. The items of this questionnaire are rated within three answer categories ranging from 1 = "never" to 3 = "often". The Global Executive Composite Score consists of 86 (point-values: 86-258. The Behavioral Regulation Index contains 28 items (point-values: 28-84), whereas the Cognitive Regulation Index includes 44 items (point-values: 44-132). Higher scores indicate increasing problems with behavioral and cognitive regulation and overall executive functions.	Baseline at week 1, post-measurement at week 10, follow-up-measurement at week 30
Continuous Performance Test (CPT, Knye et al., 2003)	Computerized attention test for objective measurement of Reaction Times and Variability, Commission Errors and Omission Errors.	Baseline at week 1, post-measurement at week 10, follow-up-measurement at week 30

Collaborators and Investigators

• Sponsor: Bielefeld University
• Collaborators: Philipps University Marburg
• Investigators: Study Chair: Katja Werheid, Prof. Dr., Bielefeld University; Principal Investigator: Björn Albrecht, Dr., Philipps University Marburg; Principal Investigator: Luisa Himmelmeier, M.Sc. Psychology, Bielefeld University; Principal Investigator: Mira-Lynn Chavanon, Dr., Philipps University Marburg; Study Chair: Hanna Christiansen, Prof. Dr., Philipps University Marburg

Publications and helpful links

General Publications

• Eldridge SM, Chan CL, Campbell MJ, Bond CM, Hopewell S, Thabane L, Lancaster GA; PAFS consensus group. CONSORT 2010 statement: extension to randomised pilot and feasibility trials. Pilot Feasibility Stud. 2016 Oct 21;2:64. doi: 10.1186/s40814-016-0105-8. eCollection 2016.
• Drechsler, R., & Steinhausen, H. C. E. (2013). Verhaltensinventar zur Beurteilung exekutiver Funktionen: Deutschsprachige Adaptation des Behavior Rating Inventory of Executive Function: BRIEF.
• Döpfner, M., Plück, J. & Kinnen, C. (2014). Deutsche Schulalter-Formen der Child Behavior Checklist von Thomas M. Achenbach. Hogrefe.
• Knye, M., Roth, N., Westhus, W. & Heine, A. (2003). Continuos Performance Test. Hogrefe.
• Döpfner, M., & Görtz-Dorten, A. (2017). Diagnostik-System für psychische Störungen nach ICD-10 und DSM-5 für Kinder und Jugendliche-III (DISYPS-III) (3. Aufl.). Hogrefe.
• Hao Z, He C, Ziqian Y, Haotian L, Xiaoli L. Neurofeedback training for children with ADHD using individual beta rhythm. Cogn Neurodyn. 2022 Dec;16(6):1323-1333. doi: 10.1007/s11571-022-09798-y. Epub 2022 Apr 1.
• Himmelmeier L, Waltereit R, Werheid K. Multi-method ADHD diagnostics in children: CBCL and TRF lead the way. Front Psychiatry. 2025 Nov 17;16:1668149. doi: 10.3389/fpsyt.2025.1668149. eCollection 2025.

Study record dates

Study Major Dates

• Study Start (Actual): July 9, 2024
• Primary Completion (Estimated): October 31, 2026
• Study Completion (Estimated): December 31, 2026

Study Registration Dates

• First Submitted: April 15, 2026
• First Submitted That Met QC Criteria: May 12, 2026
• First Posted (Actual): May 19, 2026

Study Record Updates

• Last Update Posted (Actual): May 19, 2026
• Last Update Submitted That Met QC Criteria: May 12, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: ADHD; children; EEG-neurofeedback
• Additional Relevant MeSH Terms: Neurologic Manifestations; Nervous System Diseases; Neuromuscular Manifestations; Mental Disorders; Neurodevelopmental Disorders; Attention Deficit and Disruptive Behavior Disorders; Pathological Conditions, Signs and Symptoms; Behavior; Signs and Symptoms; Attention Deficit Disorder with Hyperactivity; Spasm; Impulsive Behavior
• Other Study ID Numbers: NF-2024-12

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No