Aim of the study:
The purpose of the study was to evaluate the efficacy of the EEG-biofeedback (NF) method in ADHD treatment in each of the three basic DSM-IV-TR clinical types.

Subject or material and methods:
85 patients aged 6 to 14 treated in an outpatient department and a day-care department (S) were qualified for the EEG-biofeedback therapy, whereas the control group consisted of 30 patients (C) who were treated with methylphenidate. For the purposes of evaluating the treatment efficacy, a structured interview on the presence of the ADHD symptoms was conducted. The S group patients participated in 20 NF therapy sessions throughout a six-month period. An analysis of electrophysiological parameters of EEG was additionally performed in group S - Th/SMR and Th/Beta ratios in C3 and C4 channels at three points in time (at the beginning, during the course of and at the end of the EEG-biofeedback therapy).

Results:
Both types of S and C group therapies significantly reduce (p < 0.01) the number of attention deficit, hyperactivity and impulsiveness symptoms in subgroups with attention deficit prevalence and mixed type. In all ADHD types, significant decrease in values of the examined Th/SMR and Th/Beta ratios was noted between the sessions 1 and 10.

Discussion:
The NF method proved similarly effective as methylphenidate in reducing the number of symptoms, both in the type with prevalence of attention deficit and in the mixed type.

Conclusions:
The results of the study are promising, since the EEG-biofeedback therapy was similarly effective as methylphenidate in reducing the aggravation of ADHD symptoms.