WO2002038049A1

WO2002038049A1 - Method and device for detecting neurological and psycho-physiological states

Info

Publication number: WO2002038049A1
Application number: PCT/DE2000/003958
Authority: WO
Inventors: Ivanova Galina Haralampieva; Gert Griessbach; Günter HENNING; Eylem Mehmet Kirlangic; Svitlana Kudryavtseva
Original assignee: Eldith Gmbh
Priority date: 2000-11-11
Filing date: 2000-11-11
Publication date: 2002-05-16
Also published as: AU2001223490A1; JP2004512152A; IL155844A0; PL198204B1; EP1333749A1; PL361338A1; CA2428258A1

Abstract

The aim of the invention relates to a method and a device for detecting and influencing neurological and psycho-physiological states. To achieve this, according to the invention, a user-specific profile for the selection of an individual training protocol is created in a central unit comprising a profiler determination support system and the corresponding software components are configured and integrated into a portable unit with a modular construction, equipped with a communication unit. A training of the activities of the user and a subsequent objective validation of the bio-feedback strategy takes place in both the central and in the portable unit, by means of methods based on signal analysis and statistical comparisons in relation to the initial state and/or a collective of norms.

Description

METHOD AND DEVICE FOR DETECTING NEURO- AND PSYCHOPHYSIOLOGIC 5CH STATES

The invention relates to a biofeedback ner driving for recording and self-regulation of neurophysiological and psychophysiological conditions, in which biosignals are determined and evaluated on a user and a device for carrying out the method.

In particular, it enables the implementation of a user-specific biofeedback system for spontaneous and evoked brain activity and its influence on interactions with the other physiological systems and is implemented on the basis of a central and a portable unit. In the field of biofeedback and in particular EEG biofeedback or neurofeedback, there are different systems, devices and methods for use in clinical practice, as described for example in the following patents:

US 5 740 812 contains a methodology and a device for EEG biofeedback during the execution of defined tasks such as working on the computer, while playing etc. The associated device consists of a headphone to which EEG sensors are attached. The recorded EEG signals are then evaluated by means of a computer, with the aid of audio and video feedback indicating the human concentration and alertness.

US 5 465 729 and US 5 343 871 describe devices for audio and video feedback, audio and video sequences emulating real scenes so that desired psychological states can be induced. Activating the desired physiological parameters is rewarded. Control of these parameters is made possible by remembering the sequences shown.

According to US 5 406 957, a biofeedback device for feedback of frequency bands, determined by means of FFT, is known. The feedback is presented in the form of acoustic signals or spoken words.

No. 5,036,858 specifies a device for audio and video feedback, in which the difference from the desired frequency is presented simultaneously with the calculated EEG frequency.

According to US 5 024 235 a device for audio and video feedback is known, in which the amplitude of an EEG frequency band is determined and in

Comparison to a threshold is displayed. US 3 890 957 describes a device for audio feedback, in which, according to the zero crossings determined in the detected signal, a DC signal is generated and this is used to modulate an audio output.

In the device for biofeedback known according to US Pat. No. 3,821,949, certain signal frequencies are determined simultaneously in several channels and corresponding acoustic signals are generated as an output after reaching a desired value.

The most common device solutions offer the possibility of

Feedback of several physiological signals such as EMG, temperature, respiration, skin conductivity and EEG. In the area of feedback of human brain activity, there are devices that implement the feedback of different EEG components such as θ, α, ß rhythms, SMR rhythm or ratios of these brain activities. The existing devices offer the trainer the limited choice of specified neurofeedback protocols, using prescribed electrode positions. A biofeedback method that is very often used in very different neuronal diseases is based, for example, on the SMR rhythm. However, the procedure is usually very unspecific, since the existing technology does not offer enough flexibility and space for individual treatment design.

Problems with regard to the requirements of a successful biofeedback strategy arise from the limitations of the EEG device technology available on the market: the measurement hardware usually does not allow the reliable detection of specific signal components, the software supplied is mostly designed for routine EEG examinations and only realizes it conventional evaluation method. For the control of feedback in EEG learning processes is a continuous online-enabled

Monitoring the frequency and amplitude changes of basic rhythms necessary. Known EEG feedback controls are based on evaluations in longer time windows or signal sections. This means that feedback on the success of rhythm control is only possible at intervals of a few seconds. There is a lack of high-resolution and topographical methods, particularly in terms of time and frequency, with which the dynamics of brain processes can be researched online, taking into account the stochastic EEG character. This means that the prerequisites for understanding the fine temporal microstructure of the physiological and pathological brain events are not present. There are also no methods for demonstrating the specificity of neurofeedback therapy because of the various influencing factors and those used for

Validation of suitable characteristics cannot be extracted and controlled sufficiently.

Practice also shows that, for example, when training epileptic users on the basis of the slow potential, the biofeedback sessions should be carried out with a frequency of at least 2-3 sessions per week over a period of several months. This turns out to be hardly feasible, in particular for working or remote users, which is why this type of treatment is often dispensed with. Difficulties also arise in a "follow-up" phase in which the users are unable to control the device due to the lack of device technology

Order correctness of the exercises.

The invention is based on the object of specifying a method and a device of the type mentioned at the beginning with which specific indications of a multiple, user-specific profile and for a monitored initial training are recorded and can also be used outside of coaching practice.

According to the invention, the object is achieved by a method which the in Features specified in claim 1 and solved with a device which contains the features specified in claim 12

Advantageous refinements are specified in the subclaims.

The invention enables the implementation of a flexible, integrated multi-channel system, which comprises components for the specific indication of a multiple, user-specific profile and for a monitored initial training. On the basis of the adapted to this central system

A protocol can be ported to a modular, individually adjustable mobile device for use at home or outside the practice of a trainer, for example for use during a "follow-up" phase. Monitoring, control and evaluation of the meetings taking place at the same time, not necessarily in one place, and readjusting the biofeedback protocols via the Internet or communication protocols can thus also be implemented.

The invention is characterized in particular by the following advantages:

• The implementation takes place with a central system and a portable miniature system that can be connected to it.

• A profiler integrated in the central unit serves as a decision support system for creating a user-specific profile on the basis of which the choice of those to be trained is made

Activities and the objective validation of the biofeedback strategy with the help of signal analysis methods and statistical tests against an initial state and against a norm group.

• The trainer can freely design interactive biofeedback protocols in the form of mathematical functions, such as (Aa (Ol) Λ- Aa (Oz) + Aa (02)) / Aθ (0z)

Sum of the amplitudes of the α activity under electrodes 01, Oz, O2 divided by the amplitude of the θ activity under electrode Oz

(P [10-12] (Oz)) / (P [8-10] (Oz)) ratio of the instantaneous power (electrode Oz) of the activity in the

Frequency range 10 <= f <= 12 Hz compared to this in the frequency range

8 <= f <10 Hz

F (P3) current frequency of activity under electrode P3 ASMR (C3)

SMR amplitude - position C3

SCP (Cz)

Slow cortical potential below Cz

C (C4) local coherence - position C4.

• The configuration of the software for the portable system is realized by putting together individual software components when setting the protocol on the central system and porting it from the central system to the portable system. • The monitoring, control and evaluation of the meetings and the

The biofeedback protocols can be reset via the Internet (for example using an integrated web chip) or using communication protocols.

• The monitoring and control of several, carried out simultaneously with the portable system, not necessarily in one place

Sessions are made possible by the central system via a biofeedback monitoring facility within practices, hospitals and studios or by means of biofeedback telemonitoring during training, for example at home. • Free choice of feedback channel or cortical location (e.g. Language center, music center etc.) can be carried out with simultaneous monitoring of the real signals and the feedback parameters of all recorded channels on the central system.

• It is possible to simultaneously record EEG components such as θ, α, ß and similar EEG rhythms of slow components

(SCP) and other polygraphic signals.

• The possibility of integrating interactions with other physiological systems, the processes of which can be trained in a supportive manner, with a constant control of their influences and the correlative and functional relationships with the primary feedback process (example: monitoring or feedback of the connection between slow brain potentials and breathing) is also realized.

• There is the possibility to detect abnormal brain activity, especially epileptic grapho elements and the request for biofeedback training.

• It also offers the opportunity to capture and feedback evoked potentials by using numerous visual, acoustic and cognitive stimulations on the central system, for example by coupling with a visual or acoustic perimeter or other visual, acoustic, somatosensory stimulation units.

• It enables a variable duration and combinability of the feedback trials, the interstimulus distances and the pauses on the central system.

• The choice of different signal processing methods or parameters for the same channel or for different channels and their simultaneous display to optimize the feedback protocol on the central system.

• The use of adaptive recursive estimates as the basis for the continuous online control of the feedback. »It includes multimedia feedback modules that are individual by choice or import of music, film files, images or vibrations by the trainer, if necessary, also configured by the user. The sensitivity of the feedback can also be individually adjusted.

• The control of films as feedback, such as playing the film, will only take place as long as the corresponding activity is controlled in the desired direction. Otherwise the playback is stopped.

• The central system is expediently implemented as a two-monitor system (user and trainer monitor) either as a 2-PC system (communication e.g. via RS 232 or TCP / TP) or as

1-PC system when using internal communication (e.g. DDE, TCP / TP);

• It enables compatibility with common polygraphic and EEG systems and thus implementation on the basis of commercially available devices and does not require any special hardware solution.

• A monitor, video panel, video glasses or display attached to the head can be used for feedback.

• The portable miniature system can be implemented on the basis of a portable computer, "body-worn" computer, palmtop or game console.

Due to the high functionality, flexibility and the possibilities for individual optimization, not only is the efficiency of neurofeedback training increased, but new treatment perspectives are opened up by designing new biofeedback protocols. Last but not least, the portable solution offers the user a cost-effective alternative that allows for date independence and thus free planning. Furthermore, by combining a central system with several portable systems, biofeedback monitoring rooms can be set up for the control of the user and thereby Personnel can be saved.

The invention is explained in more detail below using an exemplary embodiment.

In the accompanying drawing:

1 shows the methodical sequence of the biofeedback method according to the invention, FIG. 2 shows the sequence diagram of a neurofeedback training,

FIG. 3 shows a schematic illustration of the neurofeedback system,

Figure 4 shows the functional diagram of the neurofeedback system, and

Figure 5 is a block diagram for a miniaturized portable unit.

As can be seen from FIG. 1, the quantification of the EEG (QEEG), which was derived by means of long-term monitoring, forms the starting point of the method. As a result, parameters describing the condition of the user can be obtained from the EEG, which was recorded at rest or, depending on the application, during different provocation methods. A user-specific profile is created using a predefined vector of parameters. In addition to the quantities resulting from the quantification, this profile also contains user-specific data, e.g. Information about the current emotional state and the environment, the history, the results of IQ or psychological tests recorded. The user-specific profile is then used to determine the strategy for neurotherapy or biofeedback. During the first biofeedback sessions, which can be described as initial, monitoring of the real signals and the feedback parameters is also carried out for all recorded

Channels performed. A choice of different ones Signal processing methods for one or different channels are also possible. After determining the optimal method for the user - i.e. choosing the activity, the cortical location, the calculation method, the start resolution of the feedback and the modalities of the stimulation paradigms, in the event of an evocation, either on the central system or on the home system (after porting of the corresponding modules) a certain number of training procedures are carried out. Long-term monitoring with subsequent quantification can then be carried out. The profile is continuously expanded with the newly acquired parameters. Comparisons between the state vectors can be carried out on the basis of selected statistical methods and according to predefined criteria. The result serves to assess the success of the applied neurofeedback therapy. The results of the evaluation serve to adapt the treatment method. This would mean that if an activity is not successfully controlled, it can be replaced in future therapy sessions by controlling another activity or by combining the control of different EEG parameters.

FIG. 2 shows the course of neurofeedback training.

As can be seen in FIG. 3, the central biofeedback system consists of the following components:

Control of measurements and stimulation, signal acquisition, signal processing, signal presentation, feedback and stimulation (optional).

The use of multichannel leads in neurofeedback examinations is essential for the initial phase. This approach allows the correlation of functional and morphological findings to be viewed in a significantly improved manner. It is expected that through the

Taking into account the topographical peculiarities of the pathological EEG signals and through efficient online monitoring a user-specific and more effective neurofeedback therapy can be designed. Furthermore, other biological signals should be derived simultaneously. In this way, valuable conclusions about time-correlating side effects or other physiological or pathological processes can be made and taken into account in the biofeedback.

In order to obtain the possibility of complete information about the physiological processes taking place, polygraphic data, including e.g. the EEG, the VEOG, the HEOG, the EKG and the respiratory curve are recorded. For the derivation of the EEG

Positions of established EEG lead systems used. The derivations are carried out referentially against the connected mastoids. Other assemblies such as transverse, longitudinal and temporal are possible. The transition impedances are brought up to <3 kΩ. The setting of the filter is in the range 0-70 Hz, whereby DC (0 Hz) is mainly necessary when deriving slow potentials (SCP). The sampling rate is between 100 and 500 Hz. The other signals are derived bipolar. The EEG and the EOG are carried out using off-set and drift-reduced electrodes. The breathing curve is recorded using a breathing belt. The one that follows after the initial investigation and feedback session

Biofeedback training takes place using a greatly reduced number of electrodes, which depends on the choice of activity.

The neurofeedback system should be flexible and give the trainer the opportunity to carry out experimental tests. For this reason, the prerequisites for monitoring both evoked and spontaneous activity should be created. In the first case, besides the provocation methods established in the neurological routine, numerous stimulation procedures are also required. Examples of this are the Sl-S2 paradigm, the odd-ball paradigm, visual stimulation using

Checkerboard or perimeter and others The demand for flexibility implies the consideration of a larger number of spontaneous and evoked parts of brain activity. In the first place, signals are selected, the experimental use of which was combined with a positive therapeutic effect as part of a neurofeedback procedure. Examples of such EEG rhythms are θ, α, ß, SMR rhythm or the combinations of these. The field of ERP includes the CNV, CPV, P300, VEP and others. Connections between different cortical locations, such as bilateral asymmetries, bilateral and local coherences, are also included. The superimposition of the relevant EEG signals with a large number of artifacts of biological and non-biological origin makes efficient preprocessing indispensable. When choosing the methods and algorithms, a compromise in terms of optimal signal quality must be made at this point due to the real-time capability.

The routines of signal processing form the core of a neurofeedback system. The results of the potential evaluation are used in four different ways:

• for artifact reduction; • For presentation of results and control by the trainer or the medical-technical staff. A combination of the directly measured and the calculated size can be created and displayed;

• to control the feedback; • for later off-line evaluation of the neurofeedback session and for statistical comparison with previous sessions or with existing average data.

In the first three cases, only methods that are due on-line are considered, or methods in which the evaluations are based on epochs (quasi on-line). Methods of the following groups are implemented according to the calculation type:

- methods based on windows, e.g. the FFT, baseline calculation, averaging, correlations, VEOG, HEOG correction; - recursive methods such as the adaptive-recursive estimates (ARE).

Through the control via the control parameter calculated from the measurement data, the current state of the feedback stands for a specific, measured physiological state of the user. The real feedback is that this condition is through a multimedia

Presentation becomes perceptible to the user (e.g. acoustically, visually or audiovisually) and a change in this state, as part of the training procedure, can only be recorded and then trained using this presentation. The design of the feedback should be simple and not too complex and should be age-dependent. In the system presented here, the feedbacks are in

In the form of high quality animations, films, pieces of music or vibrations that can be controlled via RS 323, DDE or TCP / IP. Both movement-oriented and performance-oriented types are implemented. An adaptation of the feedback resolution to the possibilities of the user (within the individual parameter range of the signal to be controlled) is possible. The files required for the control mechanism (images, music, films) can be inserted in certain formats by the trainer and, if necessary, by the user.

The basis of the central system is a polygraphic EEG device (DC-AC amplifier). This offers the possibility of making the measuring arrangements flexible. A possible configuration would be, for example: 28 unipolar channels EEG and 4 bipolar channels for VEOG, HEOG, EKG and breathing.

Figure 4 explains the functional diagram of the neurofeedback system. To the To establish the required feedback, the data stream must first be transmitted from the amplifier to the measurement computer. A parameter that is used to control the feedback is then calculated from the raw data. The design of the control of the feedback in the three ways described (via RS 323, DDE or TCP / EP) allows the central to be implemented

Systems using two PC's and two screens or also by a PC and one or two screens. The portable unit is realized on the basis of portable computers, "body worn" computers, palm tops or game consoles. Both the common and portable system can use either common monitors, such as TFT displays, as well as special LCD glasses with integrated headphones, such as a personal LCD monitor or a "head mounted" display. The options mentioned allow additional miniaturization and mobile use of the portable solution. The diagram of such an arrangement can be seen in FIG. 5.

LIST OF REFERENCE NUMBERS

QEEG Quantified EEG

EEG electroencephalogram

EKG electrocardiogram

BF biofeedback

NT neurotherapy

NF Neurofeedback

Sl, S2 stimulus

ISI interstimulus interval

SCP Slow Cortical Potential

DSV digital signal processing

VEOG vertical electrooculogram

HEOG horizontal electrooculogram

DDE Dynamic Data Exchange

EMG electromyogram

FFT fast (almost) Fourier transformation

VEP Visually evoked potential

ERP event-related potential

CNV contingent negative variation

CPV contingent positive variation

TCP / IP Transmission Control Protocol over Internet Protocol

PC personal computer

EOG electrooculogram

Claims

PATENT TO SPEECH

1. Biofeedback method for recording and influencing neurological and neuropsychological conditions, in which biosignals, in particular the spontaneous and evoked brain activity and their interactions with the other physiological systems are determined and evaluated on a user, characterized in that in a central unit with a profiler decision support system, a user-specific profile for the selection of an individual training protocol is created and the associated software components are configured and ported to a modular portable unit equipped with a communication unit, with training from both the central and the portable unit Activities of the user and subsequently an objective validation of the biofeedback strategy with the help of signal analysis

Procedures and statistical comparisons are made with respect to the initial state and / or against a norm collective.

2. Biofeedback method according to claim 1, characterized in that a multiple, user-specific neurofeedback profile is determined with a flexible, integrated, multi-channel central system and a training protocol is created on the basis thereof.

3. Biofeedback method according to claim 1 or 2, characterized in that the trainer provides a free interactive design of biofeedback protocols by defining mathematical functions.

4. Biofeedback method according to one of claims 1 to 3, characterized in that the feedback channel or the cortical localization is selected with simultaneous monitoring of the real signals and the feedback parameters of all detected channels.

5. Biofeedback method according to one of claims 1 to 4, characterized in that abnormal brain activities are detected and the user is signaled the need for biofeedback training.

6. Biofeedback method according to one of claims 1 to 5, characterized in that individual software components are configured by the choice of the protocol and are transferred to the portable system.

7. Biofeedback method according to one of the preceding claims, characterized in that a coupling of the central device and portable device for monitoring, checking and evaluating the sessions and for resetting the biofeedback protocols is carried out by transmission over the Internet or via communication protocols.

8. Biofeedback method according to one of the preceding claims, characterized in that EEG components, ERP and / or other polygraphic signals are recorded simultaneously.

9. Biofeedback method according to one of the preceding claims, characterized in that interactions with other physiological systems are taken into account and trained in a targeted, supportive manner, with constant monitoring of their influences and the correlative and functional relationships.

10. Biofeedback method according to one of the preceding claims, characterized in that evoked potentials are detected and / or controlled through the use of visual, acoustic and cognitive stimulations.

11. Biofeedback method according to one of the preceding claims, characterized in that different signal processing methods or those with different parameters for the same or for different channels are displayed simultaneously.

12. Device for performing the method according to one of claims 1 to 11, characterized in that the device contains a central system and a portable system, the central system including a flexible multi-channel system and a profiler decision support device is integrated in the central system and the portable

System contains a modular, individually adjustable mobile device.

13. The apparatus according to claim 12, characterized in that the central system and the portable system contains interfaces for the Internet and / or for communication protocols.

14. The apparatus according to claim 12 or 13, characterized in that the device contains means with which, via the central system, a monitoring and control of several simultaneous sessions at one place, in the sense of a NF monitoring or at a remote place in the sense NF telemonitoring is realized.

15. Device according to one of claims 12 to 14, characterized in that the central system and the portable system are coupled to devices for visual, acoustic and / or cognitive stimulations.

16. The device according to one of claims 12 to 15, characterized in that the device contains means with which the duration and combinability of the feedback trials, the interstimulus distances and the pauses is selected variably and individually.

17. Device according to one of claims 12 to 16, characterized in that the device contains means with which films, and / or pieces of music, and / or images and / or vibrations are integrated by the trainer or user.

18. The apparatus according to claim 17, characterized in that the device contains means with which the control of films is integrated as feedback.

19. Device according to one of claims 12 to 18, characterized in that the monitor or video panel, television, video glasses or display attached to the head is selected for the feedback.

20. Device according to one of claims 12 to 19, characterized in that the central system as a two-monitor system (user,

Trainer-Monitor) either as a two-PC system (communication - RS232, TCP / IP) or as a one-PC system when using internal connections (DDE, TCP / TP).

21. Device according to one of claims 12 to 20, characterized in that the portable system contains portable computers, "body-worn" computers, palmtops or game consoles.