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The statistical multi-stage method is applied to a recorded EEG signal, decomposing it into a number of key components (EEG oscillations, their relations and dominance; wave shapes; distribution of EEG oscillations, their amplitude, power and dominant frequency; interhemispheric and anterior-posterior asymmetry; focuses of pathological activity; paroxysmal activity) characterizing the signal. Based on these components and the principles of the information theory the typization of qEEG signal is obtained and the degree of deviation from the optimal norm is estimated.

A comprehensive quantitative EEG (qEEG) analysis compares the electrical activity generated from your brain with an optimal reference of healthy individuals of your age and gender (normative reference) and specific neuropathology group (pathologic reference) when needed. This can help identify optimal, suboptimal and abnormal functioning in the brain, degree of these abnormalities and also shed light on the nature of those abnormalities.

In this way the probability that an individual belongs to specific categories or a subtype within a category is evaluated.

The optimal range of qEEG characteristics represents certain ideal characteristics displayed by a majority of subjects in the same age group, without current or past neurologic or mental complains, without other illnesses or traumas (physical or psychological) that might be associated with brain dysfunction, without history of substance abuse and without family history of neurologic and psychiatric diseases.

Deviation from the optimal range does not necessarily reflect abnormality or a pathological process. Deviation means that the brain functions outside the optimal range, thus spending more energy and resources to achieve needed results/aims. In another words, brain works less efficiently.

If compensatory mechanisms of the brain are intact, then the qEEG characteristics’ deviation is pathogenically insignificant. However, the pathogenic significance of qEEG deviations from optimal range increases when compensatory mechanisms of the brain are exhausted. This is usually associated with strong and very strong deviations from the optimal level.

Interpretation of the qEEG includes information regarding qEEG data based on published scientific research and careful consideration of other signs and symptoms that an individual presents with.

Advanced analysis of functional brain activity measured by electroencephalogram (EEG) provides a rapid screening for functional state of the brain, estimates its predispositions and neural and mental capabilities.

It is a very simple procedure. A standard qEEG assessment takes approximately half an hour to complete. EEG cap and electrodes are placed on the subject’s head. The positions for electrodes are standardized so that data from different laboratories or clinics can be compared more easily to one another.

The skin at each location is cleaned and prepared to ensure good electrode contact and therefore, good conductance of electrical signals from the brain to the electrodes. A small amount of hypoallergic paste or gel is applied between the electrode and the scalp to further enhance signal conductance. Subject preparation may take 15 - 20 minutes using this approach. EEG cap is anchored to the subject using elastic straps and connected to the EEG system via a strap that contains all of the information from the electrodes.

After subject is prepared, the EEG recording is performed lasting about 12 minutes. Subject asked to remain quiet, still and as relaxed as possible for 6 minutes with his/her eyes closed and then 6 minutes with his/her eyes opened. This followed with several brief (few seconds) and alternating episodes of closed and open eyes. After completion of recording, the electrodes and the electrode cap are removed and excess gel or paste is cleaned from the scalp. You may want to wash your hair to rinse out the gel that is used in the cap. We have a space where you can wash your hair. Hypoallergic shampoo and towels are available.

After the examination, your data is processed and sent to the database of BM-Science centre. Within few days the report is produced and there will be a possibility to order personalised recommendations (a) for personalised coaching/training strategies (see BrainID services), (b) for personalised meditation strategies and exercises (see EEG-Guided-meditation and KalpaTaru services), (c) additional qEEG-screenings (see qEEG-screenings service) and (d) for personalised nutritional and dietary strategies (see NeuroNutrition service).

Studies of the closed-eyes resting state provide an important opportunity to examine baseline EEG patterns unbiased by any task. The resting-state condition avoids the confounding effects of visual scenes, instructions, and task execution (i.e., expectation matching, strategies employed, motivation or lack of it, fatigue and anxiety associated with task performance). Additionally, resting state seems more self-relevant than standard cognitive tasks, which typically drive subjects to direct their attention away from their personal concerns. The resting-state condition permits assessment of “pure” self-relevant baseline brain activity. This activity reflects individual type of spontaneous processing of an internal mental context (top-down processing), such as random episodic memory and related imagery, conceptual processing, stimulus-independent thought, self-reflection, internal “narrative,” and “autobiographical” self. The frequently expressed concern that unconstrained brain activity varies unpredictably does not apply to the passive resting-state condition of the human brain. Scientific studies have shown that it is rather intrinsically constrained by the default functionality of the resting-state condition that comprises individual neurophysiological type.

In this context resting state EEG manifests the baseline mechanics of self-organization that regulates the multiple brain systems adapting the brain and body to an ever-changing environment. Thus, resting state EEG reflects intrinsic baseline/default activity that instantiates the maintenance of information for interpreting, responding to and even predicting environmental demands.

The human brain represents only 2% of total body mass but consumes 20% of the body’s energy, most of which is used to support resting ongoing neuronal signaling. Task-related increases in neuronal metabolism are usually small (<5%) when compared with this large resting energy consumption. These facts support the importance of resting state neuronal activity that consumes most of the brain’s energy.

The resting state constitutes a reference baseline, relative to which all cognitive and physiological states can be considered. Cognitively driven fluctuations cannot be interpreted except in the context of the default system. The default mode of brain activity at rest has a specific functional connotation with cognitive and emotional processes revolving around the subject’s internal state instead of current external events or circumstances.

Thus, patterns of resting state qEEG serve as a functional localizer (“context”), providing a priori information about the way in which the brain will respond across a wide variety of tasks and conditions (“content”).

qEEG helps:

  • To identify the neuro-physiology of mental status changes: are these changes diffuse or focal, are there epileptiform or other specific patterns, or are these changes possibly functional or psychogenic.
  • To identify the presence, localisation, persistence and type of seizure activity.
  • To identify a psychiatric nature of individual’s abnormal behaviour.
  • To evaluate the extent of an organic basis for the individual’s complaints and degree of severity.
  • To evaluate a functional state of the brain.
  • To evaluate cognitive, emotional and motivational strategies involved in mental activity.
  • To identify the weaknesses and strengths in the organization and neurophysiological status of the individual's brain.
  • To establish a baseline of the present level of brain (dys)functioning in order to be able to detect stability, improvement or recovery (or lack of it) in the future and assess the prognosis of the individual.
  • To select specific psychotropic medications based on specific electrophysiological findings associated with clinical symptoms.
  • To screen for potential risks of neurological/psychiatric diseases that individual may have or will have in future.

It is a “window” into your brain and objective assessment of neural and mental capabilities.

EEG is fast, non-invasive, painless and precise measure of brain functional activity. The intimate, dynamic structure of this activity is information-rich about the underlying cellular and intercellular processing, brain physiological, cognitive and mental functions and resources, brain states and conditions. Thus, EEG reflects functional brain state.

Digital EEG is the digitally recorded electrical activity generated by the brain. In general, EEG is obtained using electrodes placed on the scalp according to an International 10-20 System with a conductive gel (see Digital EEG Registration Procedure). In the brain, there are millions of neurons, each of which generates small electric voltage fields. The aggregate of these electric voltage fields creates an electrical reading which electrodes on the scalp are able to detect and record.

The core principle of quantitative EEG (qEEG) lies in "precise and objective quantification" of electrophysiological brain activity by computerized analytic and statistical techniques. It permits to extract more precise information from the brain electrical activity than when using the conventional simple un-aided visual inspection of EEG signal. qEEG evaluates the manner in which a particular person’s brain physiological, cognitive and mental functions organized and how brain uses its strength and resources to cope with stress or disease and compensate it.

Numerous studies proved stability and specificity of certain qEEG parameters. These parameters were being studied quantitatively in large samples of healthy functioning individuals across different nations and wide age ranges. These studies confirmed the high specificity of normative distributions of qEEG parameters within different EEG frequencies (delta, theta, alpha, and beta bands). Positive findings different from the normative values in healthy, normally functioning individuals have repeatedly been shown to be within the chance levels, with very high test-retest reliability. Normative data have been extended to cover the age range from 1 to 95 years for each EEG electrode in the standardized International 10-20 System and include many parameters of qEEG. The independence of the normative qEEG descriptors from cultural and ethnic factors enables objective assessment of brain functional state and integrity in individuals of any age, origin or background.

Scientific literature on qEEG shows that as many as 89% of EEGs in neurological and as 68% of EEGs in psychiatric patients provide evidence of pathophysiology, and these results have additional utility beyond simply ruling out “organic brain lesions”. Such EEG studies may also aid in differential diagnosis, treatment selection, and evaluation. For example, several longitudinal studies have shown that initial qEEG profiles may distinguish among patients with the same DSM diagnosis who will respond preferentially to different medications or who will display different evolution of illness. In the Position paper of the American Medical EEG Association on qEEG it is concluded that qEEG is of high clinical value now in dementia, mood disorders, mild head injury, learning disabilities and attention disorders, and schizophrenia and developments. Additionally, qEEG “scientific,” “technical” and “other specialized” knowledge meets the standards of the Supreme Court rulings, thereby supporting qEEG as an admissible and clinically valid method in the evaluation of the nature and severity of neuropsychiatric disorders.