| dc.description.abstract | Study 1: The theta/beta ratio (TBR) study
Significantly elevated levels of power in the QEEG theta band or the theta/beta ratio (TBR) were
found in 26% of the ADHD patients compared with 2.5% of controls. Excess theta was correlated with
inattention and executive problems. Finding excess theta or TBR in a patient strengthens the
hypothesis that ADHD is a correct diagnosis, as this pattern is not associated with common comorbid
diagnoses in child psychiatry. Our findings were in agreement with most of the recent research.
Study 2: The neurofeedback (NF) study
In this randomized pilot study, 30 sessions of NF were compared with stimulant medication. At
evaluation, 6 to 9 months after onset of treatment, we found significant reductions of ADHD
symptoms in the medication group, with large effect sizes, but no significant reductions in the NF
group. We argue that NF is best suited for carefully selected groups.
Study 3: Predicting acute side effects of stimulant medication
In general, about 30 % of ADHD patients treated with stimulants suffer from acute side effects
requiring adjustments, like regulations of doses and timing, change to an alternative drug, counseling
regarding sleep patterns and food intake, or a total reliance on nonpharmacological treatments. The
most common side effects (SEs) within our sample were increased irritability, anxiety, and problems
with sleep and appetite. In this study of 37 patients without SEs and 33 with SEs, a logistic regression
model showed that three variables contributed significantly to the prediction of SEs: an elevated ERP
index of anxiety; a close-to-normal ERP component, measuring action preparation; and a fast
reaction time in the VCPT task.
Study 4: Predicting the clinical outcome of stimulant medication
In this study (N = 98), 76% of the ADHD patients treated with stimulants were considered responders.
The clinical outcome (i.e. responder or nonresponder, based on interviews and rating scales) was
best predicted by electrophysiological parameters. Compared with norms, responders were
characterized by excess theta—a close-to-normal ERP component related to identification of targets,
and a smaller-than-normal ERP component related to inhibition. The brain dysfunctions of the
responders appear to be primarily associated with prefrontal lobe hypo-activation. The
nonresponders seemed to be more deviant in parietal-occipital functions. A significant moderate
negative correlation was found between side effects and clinical response.
Our conclusions
Diagnoses in psychiatry are based on observed behavior. Supplementing these observations with
variables from neurophysiology (QEEG and ERP components) and neuropsychology may increase the
professional and public credibility of diagnoses like ADHD by documenting deviances in brain
function. Such data are potentially helpful in making differential diagnoses, especially in cases in
which data from different informants do not coincide. The same parameters are promising
candidates for predictions of treatment effects. Our studies can be seen as making small
contributions to the development of biomarkers for ADHD.
Neurofeedback for ADHD cannot yet be considered evidence-based treatment. It seems to be best
suited for carefully selected cases. | nb_NO |
