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Long term effects after feedback of slow cortical potentials and of theta-beta-amplitudes in children with attentiondeficit/hyperactivity disorder (ADHD)



Though it had already been shown in the 1970s that neurofeedback improves attention, academic performance and social behavior in children with ADHD, it has not been considered as a standard therapy so far. This is mainly due to the small number of controlled studies fulfilling methodological standards -especially long term data was not available so far. We are the first to present long term data of children undergoing neurofeedback training. 47 patients in the age of 8 – 12 years were randomly assigned to two different training groups. One group was trained to self regulate slow cortical potentials (SCP), the other group tried to influence Theta-and Beta-amplitudes. Follow-up evaluation was carried out 6 months and more than 2 years after the last training session. Eleven children of the SCP group and 12 children of the Theta/Beta group took part in three booster sessions. Parents rated behavioral symptoms as well as frequency and impact of problems. Attention was measured with the Testbatterie zur Aufmerksamkeitsprüfung (TAP).All improvements in behavior and attention that had been observed at previous assessments turned out to be stable. Yet another significant reduction of number of problems and significant improvement in attention was observed. EEG-self regulation skills were preserved. In each group, half of the children no longer met ADHD -criteria. Neurofeedback appears to be an alternative or complement to traditional treatments. The stability of changes might be explained by normalizing of brain functions that are responsible for inhibitory control, impulsivity and hyperactivity.
International Journal of Bioelectromagnetism
Vol. 10, No. 4, pp.209-232, 2008
Long term effects after feedback of slow cortical
potentials and of theta-beta-amplitudes in children with
attention-deficit/hyperactivity disorder (ADHD)
Cihan Gania, , Niels Birbaumera, Ute Strehla
a Institute of Medical Psychology and Behavioral Neurobiology
Correspondence: Ute Strehl, Institute of Medical Psychology and Behaioral Neurobiology, University of Tübingen,
Gartenstr. 29, 72074 Tübingen, Germany. E-mail:
Abstract. Though it had already been shown in the 1970s that neurofeedback improves attention, academic
performance and social behavior in children with ADHD, it has not been considered as a standard therapy
so far. This is mainly due to the small number of controlled studies fulfilling methodological standards -
especially long term data was not available so far. We are the first to present long term data of children
undergoing neurofeedback training. 47 patients in the age of 8 – 12 years were randomly assigned to two
different training groups. One group was trained to self regulate slow cortical potentials (SCP), the other
group tried to influence Theta- and Beta-amplitudes. Follow-up evaluation was carried out 6 months and
more than 2 years after the last training session. Eleven children of the SCP group and 12 children of the
Theta/Beta group took part in three booster sessions. Parents rated behavioral symptoms as well as
frequency and impact of problems. Attention was measured with the Testbatterie zur
Aufmerksamkeitsprüfung (TAP).All improvements in behavior and attention that had been observed at
previous assessments turned out to be stable. Yet another significant reduction of number of problems and
significant improvement in attention was observed. EEG-self regulation skills were preserved. In each
group, half of the children no longer met ADHD - criteria. Neurofeedback appears to be an alternative or
complement to traditional treatments. The stability of changes might be explained by normalizing of brain
functions that are responsible for inhibitory control, impulsivity and hyperactivity.
Keywords: Neurofeedback; ADHD; Slow cortical potentials (SCPs); Theta/Beta – ratio; long term effects.
1. Introduction
Though stimulant medication is regarded as the most effective therapy for attention deficit
hyperactivity disorder (ADHD), till recently there were no studies demonstrating evidence for long-term
benefits from pharmacotherapy [Goldman, Genel et al., 1998]. Children, who discontinued medication,
experience a considerable loss of improvement at follow-up. Only lately the “3- year follow-up of the
NIMH MTA Study” [Jensen, Arnold et al., 2007] showed that early advantages of medication management
compared with behavioral therapy and community care were no longer present at 3- year follow-up. In
addition, a large number of non-responders - approximately 25% [DuPaul and Connor, 1998] - and side
effects of stimulant medication, such as several vegetative complaints [Schachter, Pham et al., 2001] and
reduced growth [Swanson, Elliott et al., 2007] have led to an increased demand for alternative therapy
options .
Neurofeedback has been used as a treatment for attention deficit hyperactivity disorder since the
1970s [Lubar and Shouse, 1976] when scientist recognized, that children with seizure disorders improved
at school when they were treated with neurofeedback. In the beginning neurofeedback was dismissed as
poorly researched and overly hyped, yet several studies have shown that after neurofeedback behavioral
problems, attention, academic performance, and social behavior are improved [Lubar and Lubar, 1984].
Neurofeedback protocols mainly aim at two different electrophysiological patterns. Children with
ADHD show increased Theta and decreased Beta activity in their spontaneous EEG [Monastra, Lubar et al.,
1999] and event- related potentials in children with ADHD are characterized by decreased amplitudes and
prolonged latencies compared to healthy children [Johnstone, Barry et al., 2001].
Although several studies had shown that feedback of EEG frequencies leads to improvement of
symptoms neurofeedback has not been acknowledged because of methodological shortcomings (e.g. no
randomization, no EEG data, no controls, no follow-up [Ramirez, Desantis et al., 2001] ). Since 2002 this
has changed to the better. Two controlled studies showed that neurofeedback of spontaneous EEG activity
(e.g. theta and beta) leads to the same improvements in behavior and academic performance as medication
[Fuchs, Birbaumer et al., 2003] and that improvement after a therapy combining medication, parental
counseling and individual school counseling endured after washout of medication only if neurofeedback
had been added [Monastra, Monastra et al., 2002].
Self regulation training of slow cortical potentials aims at the deviant latencies and amplitudes of
event related potentials. Slow cortical potentials (SCPs) are a special type of event related potentials
reflecting the excitation threshold of the upper cortical layer. They are slow direct current shifts. SCP shifts
in the electrical negative direction reflect a reduction of the excitation threshold while shifts in the electrical
positive direction reflect an increase of the excitation threshold [Rockstroh, Elbert et al., 1989]. Children
with attentional problems have an impaired ability to regulate their SCPs [Rockstroh, Elbert et al., 1990].
There is only a small number of studies aiming at self-regulation of SCPs [Heinrich, Gevensleben et al.,
2004] [Strehl, Leins et al., 2006]. [Heinrich, Gevensleben et al., 2004] showed a reduction of ADHD
symptoms by 25 % after training of slow cortical potentials with neurofeedback. [Drechsler, Straub et al.,
2007] showed that children with a diagnosis of ADHD who underwent neurofeedback training of slow
cortical potentials improved more than children who had participated in cognitive behavior group therapy.
Yet the vast majority of studies so far has examined self-regulation training of
electroencephalogram (EEG) frequency bands. In most cases the training rationale with ADHD patients
was to decrease activity in the Theta band and to increase activity in the Beta band.
In a randomized study neurofeedback of Theta/Beta Frequencies or SCPs, [Leins, Goth et al., 2007]
treated children between 8 and 13 years with either with a Theta / Beta or a SCP protocol. They
demonstrated that children gained the ability to self regulate cortical activity. Moreover patients improved
significantly in attention and IQ, as well as in behavior. The results remained constant six months after the
end of training. For the current study the same population was re-invited for the 2 year follow-up. We
present the first randomized long-term follow-up study, providing EEG data from neurofeedback sessions 2
years after the end of treatment. Furthermore behavioral ratings have been assessed and associated with the
EEG data.
The goal of the 2 year follow-up is to determine a) whether patients kept the ability to self regulate
cortical activation, b) whether improvements in attention and behavior remained stable and c) whether the
different treatments lead to differences in the stability of cortical self regulation and clinical effects.
2. Methods
2.1. Study Design and Participants
Figure 1 shows the schedule of the whole study and the number of children participating at each
assessment point. 23 children participated in the 2 years follow-up assessment, 11 out of the SCP-Group
and 12 of the Theta/Beta group. For our study the assessment points “screening”, “end of treatment” and “2
year follow-up” were included. Detailed comparisons between screening, end of treatment and six month
follow-up have been reported by [Strehl, Leins et al., 2006] and [Leins, Goth et al., 2007]. Due to the
earlier time of data analysis in [Strehl, Leins et al., 2006] and [Leins, Goth et al., 2007], sample sizes in
those articles might deviate from the ones given in Figure 1.
Figure 1. Study design and schedule (SCP = Slow cortical potentials. T/B = Theta/Beta ratio.) Note: Only patients
who completed the first 30 sessions are included in the graph. Drop-out rate between “Screening” and “End of
training”: 2 in the SCP and 3 in the Theta/Beta group.
Participants were recruited from the outpatient clinic for psychotherapy at the University of
Tübingen and from local psychiatric practitioners and psychotherapists. Approval was obtained from the
local ethics committee of the faculty of medicine according to the convention of Helsinki.
Each child met DSM-IV criteria for ADHD inattentive, hyperactivity or combined type and was aged
between 8 and 13. Children with a Full-Scale IQ of <80 or additional neurological conditions were
excluded. After parents and children had signed written informed consent, children were randomly assigned
to treatment. Children were matched according to age, sex, IQ, diagnosis and medication. Parents and
children were blinded according to group assignment (Theta/Beta or SCP Feedback).
In order to evaluate long-term outcome, self regulation skills, behavioral symptoms and variables
of attention were assessed as follows:
- 3 sessions EEG Feedback
- DSM IV questionnaire for parents
- Eyberg Child Behavior Inventory [Eyberg, 1999]
- Conners’ Rating Scale (Translated into German) [Conners, 1997]
- Testbatterie zur Aufmerksamkeitsprüfung, Version 1.7 [Zimmermann, 2002]
At preceding assessment points following instruments had been used in addition:
- Kindl-Questionnaire for Measuring Health-Related Quality of Life in Children and Adolescents,
parents’ and children’s version [Ravens-Sieberer, 2003]
- German Version of Wechsler Intelligence Scale for Children: Hamburg-Wechsler-Intelligenztest
für Kinder [Tewes, 1999]
- DSM-IV – questionnaire for teachers to assess DSM-IV-criteria for ADHD.
Because of possible practice effects the Intelligence Scale was not applied at the 2 year follow-up.
As most children’s teachers had changed between screening and 2 year follow-up, and because parents did
not want to involve school any more (especially if symptoms had vanished), it was decided to do without
teachers’ ratings.
Parents whose children did not participate at the 2 year follow-up were interviewed by telephone
and were asked for their reasons to decline the invitation.
2.2. Neurofeedback sessions in the 2-year follow-up
Setting, instruments and trainer were identical in both groups. The only but fundamental
difference between both groups consisted in the feedback signal. Although detailed descriptions have been
given elsewhere [Strehl, Leins et al., 2006; Leins, Goth et al., 2007] basic information about the two
different training modalities will be repeated here.
Training of slow cortical potentials
Slow cortical potentials can be observed with a latency of about 500ms after stimulus onset and
may endure several seconds. They reflect the excitability of brain areas. Electrically negative SCPs
decrease the excitation threshold while positive SCPs increase this threshold. It is assumed that developing
self regulation skills will help to improve the symptoms of hypoarousal in children with ADHD.
Children were seated in an armchair in front of a 17’’ monitor in a distance of approximately 50
inches. Electrodes were affixed on Cz, and on both mastoids, with a 10 k resistance between Cz and the
mastoids. EEG signals were amplified using an EEG 8 (Contact Precision Instruments, Cambridge, MA)
amplifier with a time constant of 16s and a low frequency filter of 40 Hz. EEG signals were digitized with a
sampling rate of 256 Hz. The slow-wave amplitude just before the beginning of the active phase of a trial
was taken as baseline and set to zero. For online and offline correction of eye movements a vertical
electrooculogram was recorded with electrodes fixed above and below the left eye.
During the active phase the slow-wave amplitude was calculated every 62.5 milliseconds as the
average of the preceding 500 milliseconds. The difference between every 500 millisecond amplitude in the
active phase and the amplitude during the baseline corresponded to the position of the feedback signal, a
yellow “ball”.
The patients saw two rectangles, one on the top and one on the bottom of the screen. A highlighted
upper rectangle indicated that a SCP shift in the electrical negative direction was demanded; a highlighted
lower rectangle indicated that a positive SCP shift was required (see Figure 2 for a picture of the screen).
Figure 2. Screens: The upper screens depict the beginning (left) and at the end (right) of a trial. The lower screens
indicate a transfer trial at the beginning (left) and at the end (right) of a trial (Figure taken from Strehl et al, 2006
[Strehl, Leins et al., 2006])
Each session consisted of 3 to 5 runs, each run included 39 trials. The ratio between negativity and
positivity tasks was 3:1. Each trial consisted of a 2 second passive phase, followed by a 6 second active
phase. Visual feedback was given by a round yellow circle (“ball” with a 1 inch diameter) that moved
upwards (negativity – so called activation) or downwards (positivity – so called deactivation)
proportionally to the cortical shift. The ball moved from left to right with a constant velocity and up and
down dependent of the amplitude of the cortical shifts. After successful trials a smiley face appeared on the
screen. Furthermore, auditory feedback was given by piano tones with high frequency (negativation) and
low frequency (positivation). A harmonious jingle at the end of a trial signalized success. Depending from
the number of correct results children received a voucher of a certain amount. This voucher could be
exchanged in a local toyshop. The value was a minimum of 3 € and a maximum of 10 € for all sessions.
In order to facilitate practice of self regulation in daily life transfer trials were inserted (see lower
panel of Figure 2). No auditory or visual feedback was given during the active phase, only the appearance
of the smiley face and the jingle at the end of a trial delivered information about success.
During the sessions the trainer sat next door and observed the EEG online on a monitor and the
child on a second monitor. Intervention was possible by a two-way intercom or by joining the child.
Training of Theta/Beta ratio
Number of runs and sessions, relation of tasks (activation / deactivation), conditions (feedback /
transfer) as well as the depiction of the feedback signal on the screen and reinforcement was identical to the
SCP-training. Different from the SCP protocol, electrodes were fixed at Cz, and additionally at C3f, which
is halfway between C3 and F3 and C4f, which is halfway between C4 and F4. Electrodes on both mastoids
were used as reference.
The feedback signal was calculated online as the averaged Theta/Beta ratio measured the averaged
activity at C3f and C4f minus the averaged ratio measured at the mastoids. Theta range was between 3 and
7 Hz and Beta range was between 12 and 20 Hz. Baseline phase was expanded to 2 seconds and feedback
phase to 7.5 seconds, as Theta and Beta frequencies show greater oscillations than SCP. An 8 second “pre-
baseline” was measured at the beginning of each training session. Integration of the Theta/Beta ratio
measured during the pre-baseline and the Theta/Beta ratio measured prior to the first trial delivered an
“overall-baseline”, which acted as a reference for the first trial. This reference was corrected online by each
new trial-baseline-ratio during the training session.
So called “activation tasks” demanded a decrease of the Theta/Beta ratio, which could be reached by
either decreasing Theta and / or increasing Beta. So called “deactivation tasks” demanded an increase of the
Theta/Beta ratio. The movement of the ball in the vertical direction reflected the current Theta/Beta ratio.
An increasing ratio resulted in a ball movement downwards, a decreasing ratio in a movement upwards. A
trial was rated as correct when in comparison to the overall-baseline-ratio the averaged ratio was lower in
“activation tasks” and higher in “deactivation tasks”.
group T/B group
Feedback signal < 1 Hz Theta (3-7 Hz) / Beta (7-20Hz)
Electrodes Cz,
mastoids Cz, C3f, C4f, mastoids
Baseline phase 2 seconds Continuous integration of 8 seconds pre-baseline (taken
before each session) and 2 seconds (taken before each trial)
Feedback phase 6 seconds 7.5 seconds
Window of Feedback
phase considered for
3-7.5 seconds
Table 1: Differences between SCP and T/B protocols
2.3. Data analysis
As can be seen from Figure 1 the design of the whole study contained 4 assessment points. Since 6
month-follow-up data are published elsewhere [Leins et al., 2007], here we compare data from screening,
end of training and 2 year follow-up.
EEG Data
According to our goal to determine long-term effects of SCP- and Theta/Beta-Feedback as a therapy
for children with ADHD we investigated whether
a) subjects of both groups were still able to differentiate between activation and deactivation tasks at
2-year follow-up
b) the difference between activation and deactivation tasks changed with time (“screening” =
sessions 2 + 3; “end of treatment” = sessions 29 + 30, “2 year follow-up” = sessions 35 + 36).
Sessions 1 and 34 were discarded as habituation sessions.
SCP - Group
For each child mean SCP amplitudes were calculated for both tasks (positivity / negativity) and
conditions (feedback / transfer) after testing for normal distribution with the Kolmogorov-Smirnov-Test for
each of the three assessment points “screening”, “end of treatment” and “2 year follow-up”).
The differences of SCP amplitudes between both tasks were analyzed for both conditions and each
assessment point by an independent samples t-test. An analysis of variance (ANOVA) with repeated
measures (time x condition x task) was performed in order to evaluate changes between assessment points.
Bonferroni-corrected post hoc paired samples tests were performed in case of a significant result in the
ANOVA. The ANOVA was corrected with Greenhouse-Geisser.
Theta / Beta - Group
The difference between the Theta/Beta ratio during the baseline phase and the ratio during the active
phase was calculated for each subject, for both conditions (feedback/transfer), both tasks
(activation/deactivation) and each assessment point (“screening”, “end of treatment” and “2 year follow-
After testing for normal distribution with the Kolmogorov-Smirnov-Test the difference between the
Theta/Beta ratio during activation and deactivation tasks was analyzed separately for feedback und transfer
tasks for each assessment point with a one samples t- test.
In order to assess possible changes of the Theta/Beta ratios an ANOVA with repeated measures
(“screening”, “end of treatment” and “2 year follow-up”) was performed for both conditions and task
(activation/deactivation). Bonferroni corrected post hoc paired samples test were applied if significant
changes with time were found.
Psychometric test data
After testing for normal distribution, test data and questionnaires were analyzed by a mixed design
ANOVA with repeated measures factors and the group factor SCP vs Theta / Beta in order to examine the
effects of time (“screening”, “end of treatment” and “2 year follow-up”). In case of a significant result in
the ANOVA post hoc paired samples tests were performed.
Effect sizes
Cohen’s d [Cohen, 1988] was used in order to assess effect sizes for each significant result after
correction with Bonferroni. Cohen’s d is equal to the differences between the means M1 - M2, divided by
the pooled standard deviation pooled = [( 1²+ 2²) / 2].
3. Results
3.1. Participants
Groups had been matched for age and IQ. See Table 2 for demographic data and diagnosis. A
comparison between the participants at 2-year follow-up still yielded no significant difference regarding to
IQ and age.
SCP Med (mg) IQ Diagosis Screening Diagosis 2 year follow up
Code Age Sex Screening Follow up Screening Hyperactivity Inattention Hyperactivity Inattention
12 8 m 0 0 85 y y n n
13 9 m 40 40 123 y y y y
19 8 f 0 0 98 y y y y
23 8 m 0 0 89 y y y n
24 8 f 0 0 126 y y y y
26 9 m 0 0 116 y y n n
30 9 m 25 20 120 y y n n
31 8 m 0 0 101 y y n n
32 9 m 15 0 111 n y n y
35 10 m 0 0 113 y y n n
40 9 m 0 0 98 n y n y
Theta/Beta 2 10 m 10 0 79 n y n n
6 9 m 15 10 112 n y n n
7 8 m 0 0 99 y n y n
8 8 m 20 5 95 y y n n
25 8 m 0 0 98 y y n n
47 8 m 0 0 100 y y y y
49 8 m 0 0 109 y y y y
58 8 m 0 0 101 y y n y
60 8 f 0 0 105 n y n n
61 12 m 0 0 92 n y n n
67 10 f 20 20 85 y y y y
69 8 m 0 0 93 y y n y
Table 2: Description of the sample before the beginning of treatment and at 2 year follow-up (y = diagnosis, n= no diagnosis).
In order to avoid biasing of our data we contacted those parents and children who did not
participate at the follow-up and asked for their reasons. In most cases lack of time was given as a
reason. Full time education was introduced in many schools in Germany at this time.
As can be seen in Table 3 there was no significant difference regarding age and IQ between
children who participated in the 2 year follow-up and those who did not. Yet in the Theta/Beta group a
significant difference in diagnosis at the 6 month follow-up could be observed. Pearson’s 2 test
showed that children who did not participate in the 2 year follow-up had a significantly higher rate of
ADHD diagnosis than children who participated.
SCP group Theta/Beta group
Participants Non-
Participants p Participants Non-
Participants p
IQ (mean) 107,27 98,64 0,076 97,33 100,1 0,49
Age (mean) 8,64 9,86 0,056 8,75 9,7 0,11
session 2+3
Combined 9 11 0,84 7 9 0,096
Inattentive 2 3 0,84 4 1 0,19
Hyperactive 0 0 1 0 0,35
6 month
Combined 3 7 0,24 2 7 0,011
Inattentive 4 4 0,67 3 1 0,36
Hyperactive 2 2 0,79 1 0 0,35
No diagnosis 2 1 0,39 6 2 0,14
Table 3: Comparison of participating and non-participating children at 2 year follow-up.
3.2. Regulation of SCPs
SCP amplitudes were distributed normally (Kolmogorow-Smirnov). Differences between
activation and deactivation tasks in the feedback condition were close to significance only at the end of
treatment (t 10 =-2,220, p=0.051, ES = 0.39). The difference was not significant at other assessment
points. No significant difference could be observed in the transfer condition.
In the feedback condition the difference between activation and deactivation tasks increased
significantly with time (F 2, 20 = 13.226, p=0.03). In the transfer condition the increase was close to
significance (F 2, 20 = 3.02, p= 0.079). Yet an F-value which is higher than “1” indicates that the p-value
is probably significant in a larger sample. A significant interaction between time x task (positivity /
negativity) could be observed for the feedback condition (F 2, 40 = 4.38, p = 0.032) but not for the
transfer condition. In the feedback condition post hoc paired samples tests revealed a significant
increase of the difference between SCP amplitudes in activation and deactivation tasks between
screening and end of treatment (t 10 = 4,22, p = 0.006, ES = 0.53). Between screening and 2-year
follow-up the increase of this difference was close to significance (t 10 = 2,789 p=0,057, ES = 0.40). At
2-year follow-up a significant decrease of the difference between SCP amplitudes in activation and
deactivation tasks in the feedback condition compared to end of treatment could be observed (t 10=-
4.494, p = 0.003, ES = 0.21).
As can be seen in Figure 3 (upper panel) SCP amplitudes in activation tasks (feedback)
increased significantly between screening and end of treatment (t 10 =3,039, p= 0.036, ES =0.47).
Between end of treatment and 2-year follow-up the mean amplitudes in negativity tasks did not change
As shown in Figure 3 (both panels), in the transfer condition children were able to produce
positive shifts in positivity tasks for the first time at 2 year follow-up, while in the feedback condition
they already had this skill at the end of training. Yet at following assessment points this ability was no
longer present.
Mean SCP amplitude, µV
Negativity tasks, feedback
Positivity tasks, feedback
Sessions 2+3 End of treatment 2
ear follow-u
p = 0.006
p = 0.057
p = 0.003
p = 0.036
p = 0.051
Mean SCP amplitude, µV
Negativity tasks, transfer
Positivity tasks, transfer
Session 2 + 3 End oftreatment 2
ear follow-up
Figure 3. Upper panel: Mean amplitudes in negativity and positivity trials in the feedback condition during
screening, end of treatment and 2 year follow- up. Lower panel: Mean amplitudes in negativity and positivity trials
in the transfer condition during screening, end of treatment and 2 year follow- up.
3.2. Self regulation of Theta/Beta ratios
Theta/Beta ratios were distributed normally (Kolmogorow-Smirnov). Differences between
activation and deactivation tasks in the feedback condition (Figure 4, upper panel) were close to
significance at the end of treatment (t 11 =-2,127, p = 0.057, ES = 0.45). The difference between
activation and deactivation tasks did not change significantly with time neither in the transfer (F 2, 22 =
0.22, p = 0.71) nor in the feedback (F 2, 22 = 0.20, p = 0.69) condition.
The increase of the Theta/Beta ratio (see Figure 5, lower panel) in deactivation tasks between
screening and 2-year follow-up was close to significance in the transfer condition (t 11 =-2.536, p =
0.084, ES = 0.31).
No further significant changes between any of the assessment points could be observed.
Mean Theta/Beta Ratio
Activation tasks, feedback
Deactivation tasks, feedback
End of trainin
ear follow-up
Mean, Theta/Beta ratio
Activation tasks, transfer
Deactivation tasks, transfer
End of 2
ear follow-
p = 0.084
Figure 4. Upper panel: Mean Theta / Beta ratios in activation and deactivation tasks in the feedback condition
during screening, end of treatment and 2 year follow- up. Lower panel: Mean Theta / Beta ratios in activation and
deactivation tasks in the transfer condition during screening, end of treatment and 2 year follow- up.
3.3. Behavior
Parental ratings
The number of DSM IV criteria for both inattention (F 2, 40 = 16.40, p=0.00) and hyperactivity (F
2, 40 = 14.59, p=0.00) decreased significantly over time. Interaction of group x time and differences
between groups did not reach significance.
As shown in Figure 5, post hoc Wilcoxon Signed ranks tests revealed significant changes for
both groups. In the SCP group a significant decrease of the number of DSM IV criteria for inattention
could be observed between screening and 2 year follow-up (Z = -2.530, p = 0.033, ES = 0.51). The
decrease of the number of DSM IV criteria from screening to 2 year follow-up for hyperactivity in the
SCP group after Bonferroni correction was close to significance (Z = -2.203, p = 0.084, ES = 0.55). In
the Theta/Beta group a significant decrease of DSM IV criteria could be observed for both
hyperactivity (Z = -2.825, p = 0.015, ES = 0.53) and inattention (Z=-2.593, asymp. sig = 0.033, Z =
0.39) between screening and 2 year follow-up.
Mean, DSM criteria
Sessions 2 + 3
End of treatment
2 year follow-up
Inattention SCP,
Hyperactivity Theta / Beta
Inattention Theta / Beta
p = 0.033
p = 0.015
p = 0.033
Figure 5: DSM IV criteria, parents' ratings. Scores below 6 are considered as normal.
Group-means for hyperactivity and inattention in both groups were below the cut-off-value of 6.
In the SCP group only 3 out of 11 children still had a diagnosis of combined ADHD at 2 year follow-
up, 5 no longer had a diagnosis of ADHD at all. In the Theta/Beta group only 3 children still had a
diagnosis of combined ADHD, 6 did not meet DSM criteria anymore. See Table 4 for further details.
Screening End of Training 2 year follow-up
Group SCP Theta/Beta SCP Theta/Beta SCP Theta/Beta
Patients 25 22 25 22 11 12
Male 20 18 20 18 8 10
Female 5 4 5 4 3 2
Diagnosis, n
ADHD 20 16 17 7 3 3
ADD, predominantly
inattentive type 5 5 5 5 2 2
ADHD, predominantly
hyperactive type 0 1 2 4 1 1
No Diagnosis of
0 0 1 6 5 6
(Ritalin, 18-60mg) 7 5 7 5 2 3
Table 4: Development of diagnosis assessed by DSM-IV questionnaire.
In both groups Fisher's exact test showed that the changes of diagnosis from screening to 2-year
follow-up are significant (SCP- group: p=0.006, Theta/Beta group: 0.03)
Frequency of problems at home and impact of problems at home were assessed by the Eyberg
questionnaire. A general linear model showed a significant change for both frequency of problems (F 2,
40 = 22.27, p = 0.00) and impact of problems (F 2, 40 = 12.436, p = 0.00). No significant time x group
interaction could be observed. Post hoc paired samples tests revealed a significant decrease of
frequency of problems in the SCP group between screening and 2 year follow-up (t 9 = 5.349, p = 0.00
ES = 0.59) and also for impact of problems (t 9 = 4.263, p = 0.006, ES = 0.34). In the Theta/Beta group
post hoc samples test also showed a significant improvement for frequency of problems between
screening and 2 year follow-up (t 11 = 4.195, p = 0.003, ES = 0.46) and also between end of treatment
and 2 year follow-up (t 11 = 3.252, p = 0.024, ES = 0.23) The impact of problems decreased
significantly in the Theta/Beta group between screening and 2 year follow-up (t 11 = 3.593, p = 0.012,
ES = 0.45). At 2 year follow-up means for frequency of problem in both groups were below the cut-off
value of 126 for the first time (see Figure 6).
Mean, Frequency
Sessions 2 + 3
End of treatment
2 year follow-up
p = 0.00
p = 0.003
p = 0.024
Figure 6. Frequency of problems, parents' ratings (Eyberg questionnaire); Scores below 127 are considered as
Sessions 2 + 3
End of treatment
2 year follow-up
p = 0.006
SCP Theta / Beta
p = 0.012
Figure 7. Impact of problems, parents' ratings (Eyberg questionnaire); Scores below 45 are considered as normal.
By using Connors rating scale parents rated their children's behavior three days in succession at
each assessment point. The changes over time were significant (F 2, 40 = 8.277, p=0.01). No time x
group interaction could be observed. There was no significant difference between the groups. Post hoc
tests showed a significant improvement for the SCP group between screening and 2 year follow-up (t 9
= 5.142, p = 0.003, ES = 0.65). As shown in Figure 8, mean values in both groups were below the cut-
off value of 15 at 2 year follow-up.
49,58 48,64
Frequency of problems
Sessions 2 + 3
End of treatment
2 year follow-up
SCP Theta / Beta
p = 0.003
Figure 8. Frequency of problems, parents' ratings (Connors questionnaire); Scores below 15 are considered as
3.4. Attention
The “Testbatterie zur Aufmerksamkeitsprüfung” [Zimmermann, 2002] was used in order to
assess attention. Seven subtests evaluated percent ranges for speed, omissions and commissions. Single
test results were aggregated to the number of results with a below-average achievement (below 25th
percentile) and to the number of results with an above-average achievement (above 75th percentile).
There was a significant decrease by time for below achievements (F 2, 40 = 28.399, p = 0.00) and a
significant increase for above achievements (F 2, 40 = 26.349, p = 0.00). No significant difference
between both groups could be observed neither for above nor for below achievements.
In the SCP-group post-hoc paired samples tests showed a significant decrease of below-average
achievements between screening and 2 year follow-up (t 10= 7.717 p= 0.00 ES= 0.54) and between end
of treatment and 2 year follow-up (t 10 = 4.404 p= 0.003 ES= 0.225). A significant increase of above-
average achievements between screening and 2 year follow-up (t 10 = -6.328 p= 0.00 ES= 0.58) could
be shown, too.
In the Theta / Beta group children showed significantly more above-average achievements (t 10 =
-4.755 p= 0.003 ES= 0.39) at 2 year follow-up compared to screening. Reduction of below-average
achievements between screening and 2 year follow-up was close to significance (t 10 = 2.593 p= 0.081
ES = 0.22). In addition a significant increase of above-average achievements between end of treatment
and 2 year follow-up (t 10 = -3.758 p= 0.012 ES= 0.25) could be observed (see Figure 9).
11,18 11,18
Number of sublets (Mean)
Sessions 2 + 3
End of treatment
2 year follow-up
Percentile < 25% T/B
Percentile < T/B
Percentile > 75%SCP
Percentile >
p = 0.00
p = 0.00
p = 0.00
p = 0.003
p = 0.003
p = 0.081
p = 0.012
Figure 9: Comparison of performance in the TAP (Test of attention).
SCP Group
p / ES
Screening End of Training 2 year follow up [scr - end] [end - 2yfu] [scr - 2yfu]
DSM Inattention 7.64 ± 1.12 6.91 ± 1.81 5.60 ± 2.11 ns ns 0.033 / 0.51
Hyperactivity 6.82 ± 1.94 6.27 ± 2.00 4.50 ± 1.50 ns ns 0.084 / 0.55
Eyberg Impact 18.09 ± 7.06 17.00 ± 7.82 12.40 ± 8.43 ns ns 0.006 / 0.34
Frequency 150.09 ± 24.87 132.64 ± 32.22 115.90 ± 20.97 0.057 / 0.29 ns 0.000 / 0.59
Connors 54.72 ± 13.60 44.63 ± 23.01 32.20 ± 12.91 ns ns 0.003 / 0.65
TAP Above achievements 11.18 ± 6.97 17.36 ± 10.22 22.09 ± 8.11 0,057 / 0.33 ns 0.000 / 0.58
Below achievements 18.27 ± 9.86 11.00 ± 9.97 6.91 ± 7.57 0.000 / 0.34 0,003 / 0.225 0.000 / 0.54
Theta/Beta Group
Screening End of Training 2 year follow up [scr - end] [end - 2yfu] [scr - 2yfu]
DSM Inattention 7.00 ± 1.28 5.25 ± 1.91 4.83 ± 2.04 0.018 / 0.47 ns 0.015 / 0.53
Hyperactivity 6.17 ± 2.37 5.00 ± 2.56 3.92 ± 2.88 0,051 / 0.256 ns 0,033 / 0.39
Eyberg Impact 16.00 ± 5.11 13.33 ± 6.62 10.00 ± 6.58 ns ns 0,012 / 0.45
Frequency 153.08 ± 26.71 138.92 ± 39.09 121.42 ± 32.85 ns 0,024 / 0.23 0,003 / 0.46
Connors 49.54 ± 18.12 48.63 ± 20.19 37.25 ± 19.81 ns ns ns
TAP Above achievements 12.00 ± 8.75 14.58 ± 10.02 19.45 ± 8.51 ns 0,012 / 0.25 0,003 / 0.39
Below achievements 16.67 ± 12.81 13.17 ± 11.93 11.18 ± 10.70 ns ns 0,081 / 0.22
Table 5. Synopsis of means and p-values in behaviour and attention. (scr = screening prior to the first sessions, end = end of training, 2yfu = 2 year follow-up)
4. Discussion
For the first time long-term data after a neurofeedback training of Theta/Beta frequency bands
and SCPs is reported. While cortical self regulation as well as improvements in behavior (parents’ and
teachers’ rating), attention and IQ have been shown to be stable six months after the end of training
[Strehl et al., 2006; Leins et al., 2007], we here present data two years after the end of treatment The
stability of self regulation of EEG as well as of concomitant changes in target behavior and attention
have been analyzed. In both groups self regulation skills and clinical outcome are stable at 2 year
follow-up.. In some cases even an additional improvement at 2 year follow-up could be observed.
EEG self regulation skills showed a mixed pattern regarding groups and conditions. In the SCP
group children gained and kept the ability to generate negative potential shifts and in the transfer
condition they continuously improved their ability to produce shifts in the positive direction A similar
observation could be made in the Theta/Beta group (feedback condition) where children continuously
improved their ability to produce shifts in the positive direction (i.e. enlarging the Theta/Beta ratio =
“deactivation”). [Strehl, Leins et al., 2006] already showed that children are able to regulate their SCPs
at the end of treatment, i.e. to differentiate between positivity and negativity tasks, and that this skill
remained stable for at least six month. At 2 year follow-up this significant difference between positivity
and negativity tasks in the SCP-amplitudes could no longer be observed. Yet it should be pointed out
that in the feedback condition this effect was caused by a decrease of the mean SCP amplitude in
positivity tasks, while the mean amplitude in negativity tasks did not change significantly (see Fig. 3).
As the skill to produce positive shifts does not seem to be as important in regard to abolishment of
symptoms, we are not expecting a negative influence on the clinical outcome. In the transfer condition
[Leins, Goth et al., 2007] had shown that at six month follow-up children were able to produce positive
SCP-shifts in positivity tasks for the first time since the beginning of treatment. At 2 year follow-up
this skill still is present. Though there is no significant difference between positivity and negativity
tasks in the transfer condition it can be seen in Fig. 3 that children were still able to produce the
required shifts, i.e. to produce positive shifts in positivity tasks and negative shifts in negativity tasks.
Participants in the Theta/Beta group were able to decrease the Theta/Beta ratio in activation
tasks ever since the beginning of treatment. The ability to increase the Theta/Beta ratio in deactivation
tasks improved continuously over time. At 2 year follow-up, patients are - as at the end of treatment -
still able to decrease the Theta/Beta ratio in activation tasks and increase the Theta/Beta ratio in
deactivation tasks. In transfer tasks, patients were not able to produce a positive Theta/Beta ratio at any
time of assessment, yet the difference between Theta/Beta ratio in activation and deactivation tasks has
nearly doubled from the end of treatment until 2 year follow-up.
Though mean SCP-amplitudes and mean Theta/Beta ratios indicate that children are still able to
self regulate cortical potentials, many results especially in the Theta/Beta group do not reach statistical
significance. This may be due to the small number of patients participating at the study. The decreasing
number of participants in long-term follow-up studies is a well-known problem.
Parents reported a reduction of behavioral problems. In each of the three questionnaires children
remained below the cut-off values. Some of these values have been reached for the first time. In the
SCP group effect sizes of these changes were mostly medium, while in the Theta/Beta Group small
effect sizes could be observed. Test results of attention testing also showed further improvements again
with medium effect sizes in the SCP group and small effect sizes in the Theta/Beta group (see Table 5
for a synopsis of all questionnaires and tests results).
Neither psychometric data nor neurofeedback data support a significant difference between both
training protocols. Being asked about their experience, many children from the SCP-group reported,
that in the first trials of each session it took them pretty long to find adequate strategies to control the
cursor. This subjective report is reflected by Figure 3 and Figure 4: While children in the SCP group
were not able to respond with appropriate shifts neither in positivity nor negativity tasks during the first
sessions, children in the Theta/Beta group were able to decrease the Theta/Beta ratio in activation tasks
from the beginning.
As can be seen from EEG training data improvements in attention and behavior do not reliably
match with the improvements regarding self regulation of brain activity in both groups. Especially in
the Theta/Beta group significant results in EEG data are very rare. Due to the absence of a control
group there is currently no proof that self-regulation training of frequency bands or SCPs leads to
improved behavior. In the preceding study [Strehl, Leins et al., 2006] had used Pearson's 2 test to
show a statistical correlation between self-regulation skills of SCPs and clinical outcome.
Unfortunately this analysis cannot be applied at this 2 year follow-up due to the small number of
How to explain the good clinical outcome given the low number of significant results in EEG
training data in the Theta /Beta group? The most obvious explanation is that non-specific factors might
contribute to the outcome. [Goth, 2006] determined predictors for clinical outcome and acquisition of
self-regulation skills in children undergoing treatment with training of SCPs or Theta / Beta bands.
While in the SCP group the acquisition of self-regulation skills at six months follow-up could be shown
to be a predictor for a good clinical outcome, factors not related to the neurofeedback training (e.g. IQ
and psychological wellbeing) were detected in Theta/Beta group.
Another important question cannot be answered by our data: 'Would the symptoms have
improved without any treatment, too? Would an improvement just be the normal course of the disease?'
Several studies already addressed this question. [Barkley, Fischer et al., 1990] showed that
approximately 80% of adolescents with a diagnosis of ADHD – despite treatment – still had significant
ADHD symptoms at 8 year follow-up. [Biederman, Mick et al., 2000] reported that a decline in
hyperactivity symptoms in untreated children with ADHD correlates with age, while inattentive
symptoms do not. Our study showed a continuous improvement in both hyperactivity and inattentive
symptoms, which indicates that there is an association between training of self regulation skills and
clinical outcome.
The heterogeneity of the samples in both groups regarding age, IQ, diagnosis and gender is a
major limitation of the study. Though both groups were matched for age and IQ, there are obvious
differences between both samples. Moreover biasing of the data in the Theta/Beta ratio group cannot be
ruled out, as children who participated in the 2 year follow-up had shown greater improvement in their
behaviour at preceding assessment points than children who did not participate at the 2 year follow-up.
In the NIMH MTA study Jensen et al showed that early advantages of medication treatment
compared with community care and behavior therapy were no longer present at 3 year follow-up.
Instead the treatment modalities applied in the study did not differ significantly in terms of reduction of
ADHD symptoms but all reached and remained below baseline levels at any point between 14 months
and 3 years. In contrast to the results of the NIMH MTA study, in our study children still improved
although treatment was terminated 2 years ago.
The present study has shown that children improved in behavior and attention after being treated
with neurofeedback and that those effects are stable or even improved two years after the last training
session took place. At 2 year follow-up approximately half of the children in both groups do no longer
meet the diagnostic criteria for ADHD at all. The long-term effects of neurofeedback can be considered
as a major advantage of this treatment compared with pharmacological treatment. Future studies
involving blind control groups should prove a causal relationship between neurofeedback treatment and
clinical outcome.
National Institutes of Health. Diagnosis and treatment of attention deficit hyperactivity disorder. Natl Inst Health Consens Dev
Conf Consens Statement. 1998:1 –37. Available at: Accessed August 24, 2006.
Barkley, RA, Fischer, M, Edelbrock, CS and Smallish, L, The adolescent outcome of hyperactive children diagnosed by research
criteria: I. An 8-year prospective follow-up study, J Am Acad Child Adolesc Psychiatry, 29(4), 546-57, 1990
Biederman, J, Mick, E and Faraone, SV, Age-dependent decline of symptoms of attention deficit hyperactivity disorder: impact
of remission definition and symptom type, Am J Psychiatry, 157(5), 816-8, 2000
Cohen, J, Statistical Power Analysis for the Behavioral Sciences., 2nd ed. Hillsdale, NJ, 1988
Conners, CK, Conners’ Rating Scale-Revised: Technical Manual in. Multi-Health Systems,North Tonawande, NY,1997
Drechsler, R, Straub, M, Doehnert, M, Heinrich, H, Steinhausen, HC and Brandeis, D, 1Controlled evaluation of a
neurofeedback training of slow cortical potentials in children with Attention Deficit/Hyperactivity Disorder (ADHD), Behav
Brain Funct, 3 35, 2007
DuPaul GJ, Barkley RA, Connor DF, Stimulants. in Attention-Deficit Hyperactivity Disorder: A Handbook for Diagnosis and
Treatment. Barkley, R. Guilford Press New York, NY,1998 510-551
Eyberg, S, Pincus D. Eyberg Child Behavior Inventory and Sutter-Eyberg Student Behavior Inventory-Revised, Eyberg Child
Behavior Inventory and Sutter-Eyberg Student Behavior Inventory-Revised in. Psychological Assessment Resources,Odessa,
Fuchs, T, Birbaumer, N, Lutzenberger, W, Gruzelier, JH and Kaiser, J, Neurofeedback treatment for attention-
deficit/hyperactivity disorder in children: a comparison with methylphenidate, Appl Psychophysiol Biofeedback, 28(1), 1-12,
Goldman, L, Genel, M, Bezman, R and Slanetz, P, Diagnosis and treatment of attention-deficit/hyperactivity disorder in children
and adolescents. Council on Scientific Affairs, American Medical Association, Jama, 279(14), 1100-7, 1998
Goth, G, Neurofeedbacktherapy bei Kindern mit ADHS: Prädiktoren für den Erwerb kortikaler Selbstkontrolle und die klinische
Verbesserung, Unpublished doctoral Thesis, 65, 2006
Heinrich, H, Gevensleben, H, Freisleder, FJ, Moll, GH and Rothenberger, A, Training of slow cortical potentials in attention-
deficit/hyperactivity disorder: evidence for positive behavioral and neurophysiological effects, Biol Psychiatry, 55(7), 772-5,
Jensen, PS, Arnold, LE, Swanson, JM, Vitiello, B, Abikoff, HB, Greenhill, LL, Hechtman, L, Hinshaw, SP, Pelham, WE, Wells,
KC, Conners, CK, Elliott, GR, Epstein, JN, Hoza, B, March, JS, Molina, BS, Newcorn, JH, Severe, JB, Wigal, T, Gibbons, RD
and Hur, K, 3-year follow-up of the NIMH MTA study, J Am Acad Child Adolesc Psychiatry, 46(8), 989-1002, 2007
Johnstone, SJ, Barry, RJ and Anderson, JW, Topographic distribution and developmental timecourse of auditory event-related
potentials in two subtypes of attention-deficit hyperactivity disorder, Int J Psychophysiol, 42(1), 73-94, 2001
Leins, U, Goth, G, Hinterberger, T, Klinger, C, Rumpf, N and Strehl, U, Neurofeedback for children with ADHD: a comparison
of SCP and Theta/Beta protocols, Appl Psychophysiol Biofeedback, 32(2), 73-88, 2007
Lubar, JF and Shouse, MN, EEG and behavioral changes in a hyperkinetic child concurrent with training of the sensorimotor
rhythm (SMR): a preliminary report, Biofeedback Self Regul, 1(3), 293-306, 1976
Lubar, JO and Lubar, JF, Electroencephalographic biofeedback of SMR and beta for treatment of attention deficit disorders in a
clinical setting, Biofeedback Self Regul, 9(1), 1-23, 1984
Monastra, VJ, Lubar, JF, Linden, M, VanDeusen, P, Green, G, Wing, W, Phillips, A and Fenger, TN, Assessing attention deficit
hyperactivity disorder via quantitative electroencephalography: an initial validation study, Neuropsychology, 13(3), 424-33, 1999
Monastra, VJ, Monastra, DM and George, S, The effects of stimulant therapy, EEG biofeedback, and parenting style on the
primary symptoms of attention-deficit/hyperactivity disorder, Appl Psychophysiol Biofeedback, 27(4), 231-49, 2002
Ramirez, PM, Desantis, D and Opler, LA, EEG biofeedback treatment of ADD. A viable alternative to traditional medical
intervention?, Ann N Y Acad Sci, 931 342-58, 2001
Ravens-Sieberer U, The KINDL Questionnaire for Measuring Health Related Quality of Life in Children and Adolescents-
Revised Version in Assessment of Quality of Life and Well-being. Schumacher J, KA, Brähler e. Hogrefe,Göttingen,
Germany,2003 184-188
Rockstroh, B, Elbert, T, Canavan, A, Lutzenberger, W and Birbaumer, N, Slow cortical potentials and behavior in. Urban &
München, Wien,1989
Rockstroh, B, Elbert, T, Lutzenberger, W and Birbaumer, N, Biofeedback: Evaluation and therapy in children with attentional
dysfunctions in Brain and behavior in child psychiatry. Rothenberger, A. Springer,Berlin,1990 345-355
Schachter, HM, Pham, B, King, J, Langford, S and Moher, D, How efficacious and safe is short-acting methylphenidate for the
treatment of attention-deficit disorder in children and adolescents? A meta-analysis, Cmaj, 165(11), 1475-88, 2001
Strehl, U, Leins, U, Goth, G, Klinger, C, Hinterberger, T and Birbaumer, N, Self-regulation of slow cortical potentials: a new
treatment for children with attention-deficit/hyperactivity disorder, Pediatrics, 118(5), e1530-40, 2006
Swanson, JM, Elliott, GR, Greenhill, LL, Wigal, T, Arnold, LE, Vitiello, B, Hechtman, L, Epstein, JN, Pelham, WE, Abikoff,
HB, Newcorn, JH, Molina, BS, Hinshaw, SP, Wells, KC, Hoza, B, Jensen, PS, Gibbons, RD, Hur, K, Stehli, A, Davies, M,
March, JS, Conners, CK, Caron, M and Volkow, ND, Effects of stimulant medication on growth rates across 3 years in the MTA
follow-up, J Am Acad Child Adolesc Psychiatry, 46(8), 1015-27, 2007
Tewes U, RP, Schallberger U, Hamburg Wechsler Intelligenztest für Kinder - Dritte Auflage (Hawik III). in. Huber,Bern,
Zimmermann P, Flimm B, Testbatterie zur Aufmerksamkeitsprüfung (TAP) in. Psychologische Testsysteme,Herzogenrath,
... In a case series by Thompson and Thompson (1998), neurofeedback was applied along with other learning strategies and showed significant improvement on various evaluation scales including IQ. Reviews and meta-analyses by Gaviria et al. (2014), Lofthouse et al. (2012) and Micoulaud-Franchi et al. (2014), concluded that application of different forms of neurofeedback were effective. Their beneficial effects are maintained in some cases up to 6 months after treatment (Arns et al., 2009;Meisel et al., 2013;Steiner et al., 2014aSteiner et al., , 2014b, in others, from 2 to 12 months posttreatment (Van Doren et al., 2019) and in 1, for 2 years (Gani et al., 2008). The meta-analysis by Riesco-Matías et al. (2021) supported the efficacy of neurofeedback and proposed a relationship between what is learned by the subject during neurofeedback training, ADHD symptoms and neurophysiological measurements. ...
... China Lévesque et al. (2006) Neuroscience Letter Canada Beauregard and Lévesque (2006) Applied Psychophysiology and Biofeedback Canada Leins et al. (2007) Applied Psychophysiology and Biofeedback Germany Gani et al. (2008) International Journal of Bioelectromagnetism Germany Holtmann et al. (2009) Kindheit und Entwicklung Germany Gevensleben et al. (2009a) Journal of Child Psychology and Psychiatry Germany Gevensleben et al. (2009b) International Content courtesy of Springer Nature, terms of use apply. Rights reserved. ...
... These effects appeared after 2 months and in the studies by Christiansen et al. (2014), Duric et al. (2017), Lansbergen et al. (2011), Leins et al. (2007, Li et al. (2013) and Meisel et al. (2013) the improvement in ADHD symptoms was maintained up to 6 months. These benefits were maintained for a period of over 6 months in the results reported by Gani et al. (2008) (6-24 months), Alegria et al. (2017) (11 months), Dobrakowski and Lebecka (2020) (12 months) and Neurofeedback Collaborative Group (2021) (13 months). Gani et al. (2008) included a follow-up evaluation carried out not only 6 months after the last training session, but also, they presented data 2 years after the end of the treatment. ...
Full-text available
Attention-deficit/hyperactivity disorder (ADHD) is one of the most prevalent disorders in children and adolescents. Neurofeedback, a nonpharmaceutical treatment, has shown promising results. To review the evidence of efficacy of neurofeedback as a treatment for children and adolescents with ADHD. A systematic review of the specific scientific studies published in 1995–2021, identifying and analyzing randomized controlled trials (RCT). A total of 1636 articles were identified and 165 met inclusion criteria, of which 67 were RCTs. Neurofeedback training was associated with significant long-term reduction in symptoms of ADHD. Though limitations exist regarding conclusions about the specific effects of neurofeedback, the review documents improvements in school, social, and family environments.
... Previous studies have reported a decrease of behavioral problems and improved cognitive performance in ADHD children after theta/beta and SCP training (Bakhshayesh, Hänsch, Wyschkon, Rezai, & Esser, 2011;Drechsler et al., 2007;Fuchs, Birbaumer, Lutzenberger, Gruzelier, & Kaiser, 2003;Gevensleben et al., 2009Gevensleben et al., , 2010Heinrich et al., 2004;Monastra, Monastra, & George, 2002;Leins et al., 2007). Moreover, some studies have found that improvements are maintained after six months (Gevensleben et al., 2010;Leins et al., 2007), and even after two years after completing the training (Gani, Birbaumer, & Strehl, 2008). Additionally, several studies have found certain normalization of EEG and ERP after NF training (Bakhshayesh et al., 2011;Doehnert et al., 2008;Heinrich et al., 2004;Kropotov et al., 2005;Monastra et al., 2002). ...
... A larger improvement for inattention in comparison to hyperactivity/impulsivity according to parents was also consistent with previous studies (Bakhshayesh et al., 2011;Drechsler et al., 2007). Concerning follow-ups, other studies that have included long-term assessments have also found that behavioral improvements were maintained after six months (Gevensleben et al., 2010;Leins et al., 2007), and even after 2 years of completing the training (Gani et al., 2008). ...
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The present study is a randomized controlled trial that aims to evaluate the efficacy of Neurofeedback compared to standard pharmacological intervention in the treatment of attention deficit/hyperactivity disorder (ADHD). The final sample consisted of 23 children with ADHD (11 boys and 12 girls, 7-14 years old). Participants carried out 40 theta/beta training sessions or received methylphenidate. Behavioral rating scales were completed by fathers, mothers, and teachers at pre-, post-treatment, two-, and six-month naturalistic follow-up. In both groups, similar significant reductions were reported in ADHD functional impairment by parents; and in primary ADHD symptoms by parents and teachers. However, significant academic performance improvements were only detected in the Neurofeedback group. Our findings provide new evidence for the efficacy of Neurofeedback, and contribute to enlarge the range of non-pharmacological ADHD intervention choices. To our knowledge, this is the first randomized controlled trial with a six-month follow-up that compares Neurofeedback and stimulant medication in ADHD.
... In addition, both groups were able to intentionally regulate cortical activity. 29,40 Reviews have concluded that preliminary results of NFT are promising. 18,29,34,36,[40][41][42] Thus, these results have spurred interest in the development of NFT using neuroimaging techniques in ADHD. ...
... 29,40 Reviews have concluded that preliminary results of NFT are promising. 18,29,34,36,[40][41][42] Thus, these results have spurred interest in the development of NFT using neuroimaging techniques in ADHD. NFT based on functional magnetic resonance imaging (fMRI) and functional near infrared spectroscopy (fNIRS) measure local oxygenated and deoxygenated blood concentrations correlated with ongoing neural circuits and results are found positive outcomes in ADHD. ...
Background: Attention deficit/hyperactivity disorder (ADHD) is a highly prevalent childhood disorder with symptoms of inattention, impulsivity, and hyperactivity. EEG neurofeedback training (NFT) is a new intervention modality based on operant conditioning of brain activity, which helps reduce symptoms of ADHD in children. Methods and procedures: To examine the efficacy of NFT in children with ADHD, an experimental longitudinal design with pre-post comparison was adopted. A total of 30 children in the age range of 6 to 12 years diagnosed as ADHD with or without comorbid conditions were assigned to treatment group (TG; n = 15) and treatment as usual group (TAU; n = 15). TG received EEG-NFT along with routine clinical management and TAU received routine clinical management alone. Forty sessions of theta/beta NFT at the C3 scalp location, 3 to 4 sessions in a week for a period of 3.5 to 5 months were given to children in TG. Children were screened using sociodemographic data and Binet-Kamat test of intelligence. Pre-and postassessment tools were neuropsychological tests and behavioral scales. Follow-up was carried out on 8 children in TG using parent-rated behavioral measures. Results: Improvement was reported in TG on cognitive functions (sustained attention, verbal working memory, and response inhibition), parent- and teacher-rated behavior problems and on academic performance rated by teachers. Follow-up of children who received NFT showed sustained improvement in ADHD symptoms when assessed 6 months after receiving NFT. Conclusion: The present study suggests that NFT is an effective method to enhance cognitive deficits and helps reduce ADHD symptoms and behavior problems. Consequently, academic performance was found to be improved in children with ADHD. Improvement in ADHD symptoms induced by NFT were maintained at 6-month follow-up in children with ADHD.
... Further, significant improvements after SCP neurofeedback were reported for oppositional behavior and physical aggression in children with ADHD 22 , criminal psychopathy 23 as well as for migraine 24 . SCP neurofeedback has been considered as the best validated standard neurofeedback protocol approach for ADHD 25,26 , with stable symptom improvements reported for diverse disorders 20,27 . ...
... Besides a reduction in the general severity of ASD symptomatology, indicated by a decrease in SRS Total score (i.e., a general improvement of social responsivity), the subscales Social Cognition and Autistic Mannerism were those that differentiated the most between the experimental and the control group. Although random differences between the SRS scores of the groups, present at the beginning of the interventions, may limit straightforward interpretations of the treatment improvements, numerous previous SCP studies support our findings of disorder-specific improvements related to SCP neurofeedback training[21][22][23][24][26][27][28] .Additionally, we observed a quadratic reduction in ASD symptomatology in both groups. This result has implications for future treatment approaches, as it can shape expectations about symptom changes during the course of treatment. ...
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Autism Spectrum Disorders are characterized by a persisting triad of impairments of social interaction, language as well as inflexible, stereotyped and ritualistic behaviors. Increasingly, scientific evidence suggests a neurobiological basis of these emotional, social and cognitive deficits in individuals with Autism Spectrum Disorders. The aim of this randomized controlled brain self-regulation intervention study was to investigate whether the core symptomatology of Autism Spectrum Disorders could be reduced via an EEG-based brain self-regulation training of Slow Cortical Potentials. 41 male adolescents with Autism Spectrum Disorders were recruited and allocated to a) an experimental group undergoing 24 sessions of EEG-based brain training (n1=21), or to b) an active control group undergoing conventional treatment (n2=20), that is, clinical counseling during a 3 month intervention period. We employed real-time neurofeedback training recorded from a fronto-central electrode intended to enable participants to volitionally regulate their brain activity. Core autistic symptomatology was measured at 6 time points during the intervention. To characterize the process of change in core symptomatology as well as the time-dependent dynamics of the training process, a Bayesian multilevel modeling approach was used. Both changes in SCP amplitudes (time-domain) and power spectral density (PSD, frequency-domain) are analyzed. The analysis revealed a substantial improvement in the core symptomatology of Autism Spectrum Disorders in the experimental group (reduction of 21.38 points on the Social Responsiveness Scale, SD = 5.29)), slightly superior to that in the control group (Evidence Ratio = 5.79). Moreover, our analyses reveal a complex and non-linear picture of neural and behavioral processes of change during neurofeedback training, which has implications for the design of future trials and training protocols.
... F. Lubar, 1991;Rossiter, 1998;Rossiter & La Vaque, 1995;Strehl, et al., 2006;Thompson & Thompson, 1998;Doehnert et al., 2008). Efficacy of EBF is comparable to psychostimulant medication and group (CBT) therapy programs with effects lasting 6 months and longer (Fuchs et al., 2003;Gani et al., 2009;Gevensleben et al., 2010;Kaiser, 1997;Leins et al., 2007;Linden et al., 1996;J.F. Lubar et al., 1995;Monastra et al., 2002;Rossiter & La Vaque, 1995;Thompson & Thompson, 1998). ...
... Evidence of group effects in the existing body of research, including several randomized-controlled trials (RCTs), shows significant efficacy of standard NFB protocols for both parent-and teacher-rated symptoms (Bakhshayesh et al., 2011;Cortese et al., 2016;Geladé et al., 2018;Gevensleben et al., 2010;Strehl et al., 2017), with a small-to-medium between-group effect size, and large effect size for within-group analysis (Cortese et al., 2016;Van Doren et al., 2019). Significant effects were also sustained at 6-12 months follow-up (Arns et al., 2012;Gani et al., 2008;Gevensleben et al., 2010;Van Doren et al., 2019). NFB training is also not limited to neurologically based difficulties like ADHD and epilepsy (Morales-Quezada et al., 2019;Walker, 2005), but it has been applied to psychogenic disorders like substance abuse disorders (Saxby & Peniston, 1995), psychopathy (Konicar et al., 2015(Konicar et al., , 2021 and PTSD (Gapen et al., 2016;Walker, 2009). ...
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NFB has a clear potential as a recognised treatment option for ADHD, but suffers from a lack of clarity about its efficacy, still unresolved after multiple controlled trials. Comparing learners and non-learners based on the evolution of patient-level indicators during the trial serves as a ‘natural’ control, and can help elucidate the mechanisms of NFB. We present a systematic review motivated by the need to establish the state of the art of patient learning during NFB treatment in current clinical literature. One particularly striking question we would like to answer here is whether existing NFB papers study learning variability, since only individual performance differences can give us information about mechanisms of learning. The results show that very few clinical trial reports have dealt with the heterogeneity of NFB learning, nor analysed whether NFB efficacy is dependent on NFB learning, even though NFB is believed to be a treatment based on learning to perform. In this systematic review we examine not only what has been reported, but also provide a critical analysis of possible flaws or gaps in existing studies, and discuss why no generalized conclusions about NFB efficacy have yet been made. Future research should focus on finding reliable ways of identifying the performers and studying participants’ individual learning trajectories as it might enhance prognosis and the allocation of clinical resources.
... Neurofeedback. This kind feedback is also often provided in classical Neurofeedback protocols during the transfer block in which participants have to performed the task without having access to real-time feedback (Gani, 2009;Janssen et al., 2016;Wangler et al., 2011). The fact that the feedback given to children is averaged over a short period of time reduces the information given to children which could have an impact on learning. ...
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ADHD is a common neurodevelopmental disorder, affecting 3-5% of the children. It refers to a variable cluster of inattention, hyperactivity and impulsivity symptoms. Neurofeedback is a rising approach to manage this disorder. This technique aims to enable subjects to learn how to modulate their own brain activity. This thesis aimed at evaluating the effects of a new Neurofeedback training protocol in children with ADHD, exploiting a neurophysiological marker that has never been used in that context, the cortical P300 response. This event-related potential reflects selective and voluntary attention mechanisms and is affected in ADHD. A randomized controlled trial (RCT) has been performed, which entailed a blind comparison with an active control condition based on gaze and a non-blind comparison with a waiting group. This Neurofeedback training was provided through visual Brain-computer Interface (BCI) games. We first demonstrated that typically developing children can control this kind of BCI. This first study also allowed us to build and evaluate a Template, corresponding to the evoked responses of these children, that was later used as the neurophysiological target in the Neurofeedback training group. In a second study, we further showed that typically developing children can control, using the Template, the three BCI games designed for the RCT and that these games could indeed be used to train the P300 component. Finally, the first analysis of the clinical data shows very few significant differences between the Neurofeedback group and the two control groups. Indeed, despite some differences in favor of the Neurofeedback or both training groups, most indicators showed an improvement of the symptoms regardless of the group. These results suggest that multiple factors may contribute to those changes including nonspecific ones such as time passing, the gaze training that was required in both active groups, or the care given to all children who followed some training. The unique and rich dataset that was collected in this study will continue to teach us and guide future research. Future studies, with a larger sample size and possibly targeting specific subgroups of ADHD children, will need to be carried out in order to further investigate the specific effect of such BCI training onto dimensions such as attention or impulsivity.
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In recent years, neurofeedback has been used as a cognitive training tool to improve brain functions for clinical or recreational purposes. It is based on providing participants with feedback about their brain activity and training them to control it, initiating directional changes. The overarching hypothesis behind this method is that this control results in an enhancement of the cognitive abilities associated with this brain activity, and triggers specific structural and functional changes in the brain, promoted by learning and neuronal plasticity effects. Here, we review the general methodological principles behind neurofeedback and we describe its behavioural benefits in clinical and experimental contexts. We review the non-specific effects of neurofeedback on the reinforcement learning striato-frontal networks as well as the more specific changes in the cortical networks on which the neurofeedback control is exerted. Last, we analyse the current challenges faces by neurofeedback studies, including the quantification of the temporal dynamics of neurofeedback effects, the generalisation of its behavioural outcomes to everyday life situations, the design of appropriate controls to disambiguate placebo from true neurofeedback effects and the development of more advanced cortical signal processing to achieve a finer-grained real-time modelling of cognitive functions.
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In this observational study the outcomes of an EEG-based infra-low-frequency (ILF) neurofeedback intervention on patients with attention deficit (hyperactivity) disorder (ADHD) are presented. The question is addressed whether this computer-aided treatment, which uses a brain-computer-interface to alleviate the clinical symptoms of mental disorders, is an effective non-pharmaceutical therapy for ADHD in childhood and adolescence. In a period of about 15 weeks 196 ADHD patients were treated with about 30 sessions of ILF neurofeedback in an ambulant setting. Besides regular evaluation of the severity of clinical symptoms, a continuous performance test (CPT) for parameters of attention and impulse control was conducted before and after the neurofeedback treatment. During and after the therapy, the patients did not only experience a substantial reduction in the severity of their ADHD-typical clinical symptoms, but also their performance in a continuous test procedure was significantly improved for all examined parameters of attention and impulse control, like response time, variability of reaction time, omission errors and commission errors. In a post neurofeedback intervention assessment 97% of patients reported improvement in symptoms of inattention, hyperactivity or impulsivity. Only 3% of the patients claimed no noticeable alleviation of ADHD-related symptoms. These results suggest that ILF neurofeedback is a clinically effective method that can be considered as a treatment option for ADHD and might help reducing or even avoiding psychotropic medication.
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Reduced seizure incidence coupled with voluntary motor inhibition accompanied conditioned increases in the sensorimotor rhythm (SMR), a 12- 14 Hz rhythm appearing over rolandic cortex. Although SMR biofeedback training has been successfully applied to various forms of epilepsy in humans, its potential use in decreasing hyperactivity has been limited to a few cases in which a seizure history was also a significant feature. The present study represents a first attempt to explore the technique's applicability to the problem of hyperkinesis independent of the epilepsy issue. The results of several months of EEG biofeedback training in a hyperkinetic child tend to corroborate and extend previous findings. Feedback presentations for SMR were contingent on the production of 12- 14-Hz activity in the absence of 4- 7-Hz slow-wave activity. A substantial increase in SMR motor inhibition, as gauged by laboratory measures of muscular tone (chin EMG) and by a global behavioral assessment in the classroom. Opposite trends in motor inhibition occurred when the training procedure was reversed and feedback presentations were contingent on the production of 4- 7 Hz in the absence of 12- 14-Hz activity. Although the preliminary nature of these results is stressed, the subject population has recently been increased to establish the validity and generality of the findings and will include the use of SMR biofeedback training after medication has been withdrawn.
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Spectral analysis of the electrophysiological output at a single, midline prefrontal location (the vertex) was conducted in 482 individuals, ages 6-30 years old, to test the hypothesis that cortical slowing in the prefrontal region can serve as a basis for differentiating patients with attention deficit hyperactivity disorder (ADHD) from nonclinical control groups. Participants were classified into 3 groups (ADHD, inattentive; ADHD, combined; and control) on the basis of the results of a standardized clinical interview, behavioral rating scales, and a continuous performance test. Quantitative electroencephalographic (QEEG) findings indicated significant maturational effects in cortical arousal in the prefrontal cortex as well as evidence of cortical slowing in both ADHD groups, regardless of age or sex. Sensitivity of the QEEG-derived attentional index was 86%; specificity was 98%. These findings constituted a positive initial test of a QEEG-based neurometric test for use in the assessment of ADHD.
Recent years have seen tremendous advances in understanding and treating Attention-Deficit/Hyperactivity Disorder (ADHD). Now in a revised and expanded third edition, this authoritative handbook brings the field up to date with current, practical information on nearly every aspect of the disorder. Drawing on his own and others' ongoing, influential research - and the wisdom gleaned from decades of front-line clinical experience - Russell A. Barkley provides insights and tools for professionals working with children, adolescents, or adults. Part I presents foundational knowledge about the nature and developmental course of ADHD and its neurological, genetic, and environmental underpinnings. The symptoms and subtypes of the disorder are discussed, as are associated cognitive and developmental challenges and psychiatric comorbidities. In Parts II and III, Barkley is joined by other leading experts who offer state-of-the-art guidelines for clinical management. Assessment instruments and procedures are described in detail, with expanded coverage of adult assessment. Treatment chapters then review the full array of available approaches - parent training programs, family-focused intervention for teens, school- and classroom-based approaches, psychological counseling, and pharmacotherapy - integrating findings from hundreds of new studies. The volume also addresses such developments as once-daily sustained delivery systems for stimulant medications and a new medication, atomoxetine. Of special note, a new chapter has been added on combined therapies. Chapters in the third edition now conclude with user-friendly Key Clinical Points. This comprehensive volume is intended for a broad range of professionals, including child and adult clinical psychologists and psychiatrists, school psychologists, and pediatricians. It serves as a scholarly yet accessible text for graduate-level courses. Note: Practitioners wishing to implement the assessment and treatment recommendations in the Handbook are advised to purchase the companion Workbook, which contains a complete set of forms, questionnaires, and handouts, in a large-size format with permission to photocopy. (PsycINFO Database Record (c) 2012 APA, all rights reserved)(jacket)
To deal with public and professional concern regarding possible overprescription of attention-deficit/hyperactivity disorder (ADHD) medications, particularly methylphenidate, by reviewing issues related to the diagnosis, optimal treatment, and actual care of ADHD patients and of evidence of patient misuse of ADHD medications. Literature review using a National Library of Medicine database search for 1975 through March 1997 on the terms attention deficit disorder with hyperactivity, methylphenidate, stimulants, and stimulant abuse and dependence. Relevant documents from the Drug Enforcement Administration were also reviewed. All English-language studies dealing with children of elementary school through high school age were included. All searched articles were selected and were made available to coauthors for review. Additional articles known to coauthors were added to the initial list, and a consensus was developed among the coauthors regarding the articles most pertinent to the issues requested in the resolution calling for this report. Relevant information from these articles was included in the report. Diagnostic criteria for ADHD are based on extensive empirical research and, if applied appropriately, lead to the diagnosis of a syndrome with high interrater reliability, good face validity, and high predictability of course and medication responsiveness. The criteria of what constitutes ADHD in children have broadened, and there is a growing appreciation of the persistence of ADHD into adolescence and adulthood. As a result, more children (especially girls), adolescents, and adults are being diagnosed and treated with stimulant medication, and children are being treated for longer periods of time. Epidemiologic studies using standardized diagnostic criteria suggest that 3% to 6% of the school-aged population (elementary through high school) may suffer from ADHD, although the percentage of US youth being treated for ADHD is at most at the lower end of this prevalence range. Pharmacotherapy, particularly use of stimulants, has been extensively studied and generally provides significant short-term symptomatic and academic improvement. There is little evidence that stimulant abuse or diversion is currently a major problem, particularly among those with ADHD, although recent trends suggest that this could increase with the expanding production and use of stimulants. Although some children are being diagnosed as having ADHD with insufficient evaluation and in some cases stimulant medication is prescribed when treatment alternatives exist, there is little evidence of widespread overdiagnosis or misdiagnosis of ADHD or of widespread overprescription of methylphenidate by physicians.
The psychiatric outcome is reported for a large sample of hyperactive children (N = 123), meeting research diagnostic criteria, and normal control children (N = 66) followed prospectively over an 8-year period into adolescence. Over 80% of the hyperactives were attention deficit hyperactivity disorder (ADHD) and 60% had either oppositional defiant disorder and/or conduct disorder at outcome. Rates of antisocial acts were considerably higher among hyperactives than normals, as were cigarette and marijuana use and negative academic outcomes. The presence of conduct disorder accounted for much though not all of these outcomes. Family status of hyperactives was much less stable over time than in the normal subjects. The use of research criteria for diagnosing children as hyperactive identifies a pattern of behavioral symptoms that is highly stable over time and associated with considerably greater risk for family disturbance and negative academic and social outcomes in adolescence than has been previously reported.
Six children were provided with long-term biofeedback and academic treatment for attention deficit disorders. Their symptoms were primarily specific learning disabilities, and, in some cases, there were varying degrees of hyperkinesis. The training consisted of two sessions per week for 10 to 27 months, with a gradual phase-out. Feedback was provided for either increasing 12- to 15-Hz SMR or 16- to 20-Hz beta activity. Inhibit circuits were employed for blocking the SMR or beta when either gross movement, excessive EMG, or theta (4-8 Hz) activity was present. Treatment also consisted of combining the biofeedback with academic training, including reading, arithmetic, and spatial tasks to improve their attention. All children increased SMR or beta and decreased slow EEG and EMG activity. Changes could be seen in their power spectra after training in terms of increased beta and decreased slow activity. All six children demonstrated considerable improvement in their schoolwork in terms of grades or achievement test scores. None of the children are currently on any medications for hyperkinetic behavior. The results indicate that EEG biofeedback training, if applied comprehensively, can be highly effective in helping to remediate children who are experiencing attention deficit disorders.
Changes in optical properties of biological tissue can be examined by near-infrared spectroscopy (NIRS). The relative transparency of tissues including the skull to near-infrared light is the prerequisite to apply the method to brain research. We describe the methodology with respect to its applicability in non-invasive functional research of the adult cortex. A summary of studies establishing the 'typical' response in NIRS vascular parameters, i.e. changes in the concentration of oxygenated and deoxygenated haemoglobin, over an activated area is followed by the validation of changes in the cytochrome-oxidase redox state in response to a visual stimulus. Proceeding from these findings a rough mapping of this metabolic response over the motion-sensitive extrastriate visual area is demonstrated. NIRS measures concentration changes in deoxygenated haemoglobin [deoxy-Hb] which are assumed to be the basis of fMRI BOLD contrast (blood oxygenation level-dependent). The method is therefore an excellent tool to validate assumptions on the physiological basis underlying the fMRI signal, due to its high specificity as to the parameters measured. Questions concerning the concept of 'activation'/'deactivation' and that of the linearity of the vascular response are discussed. To challenge the method we finally present results from a complex single-trial motor paradigm study testing the hypothesis, that premotor potentials (contingent negative variation) can be examined by functional techniques relying on the vascular response. Some of the work described here has been published elsewhere.
The effect of age on the topographic distribution of auditory event-related potentials (ERPs) recorded during a two-tone discrimination, or oddball, task was examined in two subtypes of attention deficit/hyperactivity disorder (AD/HD) as defined by the most recent diagnostic manual, DSM-IV. EEG was recorded at 17 sites from AD/HD predominantly inattentive type (n=50) and AD/HD combined type (n=50) subjects aged from 8 to 17 years 11 months. ERP components were quantified at each site. Results revealed topographic differences from controls (n=50) that were common to both subtypes (e.g. target and standard P2 amplitude, and standard P2 latency) or unique to a particular subtype of AD/HD (Inattentive type: target N1, N2, P3b and standard N2 amplitude, target P2 latency; Combined type: target N1, P2, N2 and P3b amplitude, target N2 and standard N1 latency). These group differences showed different age effects. The across-region results revealed differing patterns of abnormal component development for each subtype, indicating a qualitative difference in information processing stage deficits in each of these AD/HD subtypes.