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IntroductionThe study is based on the concept that neurological disorders (ND) lead to appearance of stable connections in the cerebral cortex; these connections arise due to adaptation of the central nervous system (CNS) to work under changed conditions.In view of serious consequences of neurological dis orders, it is necessary to identify ND as early as possible during mass screening of children [1].One of the basic methods to study how the brain and nervous system function is to perform registration and analysis of biopotentials. Depending on how impact on the patient is organized and what processing methods are used, diagnostic systems (DS) can be distinguished as systems for registration of electroencephalogram (EEG) and evoked potentials (EP).Russian companies manufacture several modern computer electroencephalographs that have similar char acteristics: MITsAR EEG (Mitsar Ltd., St. Petersburg), electroencephalograph Neiron Spektr 3 (Neirosoft, Ivanovo); computer analyzers Entsefalan EEGR 19/26 (Medikom MTD, Taganrog), system Neirokartograf (IMP MBN, Moscow), and others.To identify cortical connections that characterize the integrative activity of CNS and its deviation from the standard, in DS a function coherence device is used [4]. During the calculations, it is necessary to perform differ ent operations requiring high skills (more in mathematics than in medicine). As a result, existing DS cannot be used for neurological screening.The goal was to create an EEG based DS for ND screening in children, ensuring reduction of time and medical staff necessary for the procedure together with making conclusions on necessity to contact a doctor.The following problems were solved: development of DS structure, mathematical model of a self tuning filter (STF) and methodology for synchronization parameters quantifying on the basis of the EEG signal processing using STF, identification of reliable ND signs by the parameters of synchronization based on processing EEG of children with known diagnosis, development of algo rithm for ND diagnosis and gross CNS pathology in chil dren. Materials and MethodsTheoretical basis of the study are works of M. N. Livanov and his colleagues who believed synchronized electrical activity of the relevant parts of the cortex to be the main condition of self awareness, decision making, and associative thinking. Non gross ND (vision, hearing, minimal brain dysfunction (MBD)) from physiological perspective is primarily the inadequacy of relationships in the cerebral cortex.Development of an automated diagnostic system (ADS) was constrained by lack of an EEG signal pro cessing method that would provide complex implementa tion of heterogeneous diagnostic tasks: gross pathology identification (a requirement for screening), impairment of hearing and/or vision, minimal brain dysfunction, reg istration of visual and cognitive evoked potentials (VEP and CEP) in minimal time.An ADS should be a subsystem of gross pathology (GP) identification, especially of epilepsy. The problem A method for EEG proces...

There was proposed a method for studying and mapping the cognitive activity of the brain. The experiment simulates a flight situation: the appearance of an image, recognition, a motor act (inner speech). Electroencephalogram was recorded with cognitive load. Two figures are presented on the laptop screen- a circle and a square. At the moment of presentation of the stimulus, the matching device sends a synchronizing pulse to one of the inputs of the electroencephalogram amplifier. The subject mentally names a figure with a larger area. A selective filter system suppresses background activity. The resonant frequencies of the filters are changed to reveal a single cognitive response to a stimulus. The parameters of the model are individual for each subject. There was developed a model of a diagnostic device. The results obtained for the “circle” and “square” figures coincide at time interval corresponding to the work of the sensory visual system, but they differ at the stage of internal speech, which corresponds to pronouncing a longer word by the syllables. These results demonstrate the effectiveness of modeling in studies on the localization of the cognitive process and the diagnosis of neurological disorders.