Analysis method and real time medical or cognitive monitoring device based on the analysis of a subject's cerebral electromagnetic activity use of said method for characterizing and differentiating physiological or pathological states

• US 7,697,979 B2
• Filed: 10/14/2003
• Issued: 04/13/2010
• Est. Priority Date: 10/18/2002
• Status: Active Grant

• Current Assignee: Centre National De La Recherche Scientifique
• Original Assignee: Centre National De La Recherche Scientifique
• Inventors: Le Van Quyen, Michel, Lachaux, Jean-Philippe, Martinerie, Jacques, Renault, Bernard
• Primary Examiner(s): Marmor, II; Charles A
• Assistant Examiner(s): JANG, CHRISTIAN YONGKYUN
• Application Number:
  US10/531,311
• Publication Number:
  US 20060015034A1
• Time in Patent Office: 2,373 Days
• Field of Search: 600/544, 600/545
• US Class Current: 600/544
• CPC Class Codes: A61B 5/0006 ECG or EEG signals
• CPC Class Codes: A61B 5/369 Electroencephalography [EEG] devices for psychotechnics A61B5/16
• CPC Class Codes: A61B 5/4094 Diagnosing or monitoring seizure diseases, e.g. epilepsy
• CPC Class Codes: G16H 50/70 for mining of medical data, e.g. analysing previous cases of other patients

Abstract

A method for analyzing synchronizations of the electroencephalography of an individual using a set of sensors starting from cerebral electromagnetic analysis of the individual. The method creates a database by acquisition and digitization of electrophysiological signals output from the sensors, and calculates the degree of synchronization existing between all pairs of sensors recorded in an assembly protocol, in frequency bands between 0 and 2000 Hz, to build up the database of classes each characterizing a reference state. The method further performs statistical validation of a period analyzed in real time, which assigns this period to a class in the database, and detects a specific period with a determined degree of synchronization. A device implements this method.

Claims

1. A method of a real time medical or cognitive monitoring device for analyzing synchronizations of electroencephalography of an individual using a set of sensors starting from cerebral electromagnetic analysis of the individual, comprising:

creating a database comprising;

acquisition and digitization of electrophysiological signals output from the sensors,

calculating a correlation of phase variations between all pairs of sensors recorded in an assembly protocol, in frequency bands between 0 and 2000 Hz, to build up the database of classes each characterizing a reference state of cerebral electromagnetic activity of said individual;

statistical validation, by the real time medical or cognitive monitoring device, of a period analyzed in real time, which assigns the period to a class in the database; and

detecting, by the real time medical or cognitive monitoring device, a specific period with a determined degree of synchronization.

2. A method according to claim 1, further comprising an analysis associated with at least one type of electrophysiological signals among electrocardiograms, electrooculograms, electrodermograms, breathing signals.

3. A method according to claim 1, wherein a PLS method is used during the statistical validation, which estimates a phase difference between oscillations of signals from two electrodes.

4. A method according to claim 3, wherein a statistical level of PLS synchronization between two signals is evaluated using circular variance of the phase difference between the signals.

5. A method according to claim 3, wherein a statistical level of PLS synchronization between two signals is evaluated using normalized Shannon entropy of the phase difference between the signals.

6. Application of the method according to claim 1, to real time medical or cognitive monitoring.

7. Application of the method according to claim 1, for characterizing and differentiating physiological or pathological states.

8. Application of the method according to claim 7, for anticipating occurrence of epileptic seizures.

9. Application of the method according to claim 7, for diagnosis assistance in early stage of Parkinson'"'"'s and Alzheimer'"'"'s diseases.

10. Application of the method according to claim 7, for diagnosis assistance of schizophrenia and depression.

11. A real time medical or cognitive monitoring device starting from cerebral electromagnetic analysis of an individual, comprising:

means for acquiring and digitizing electrophysiological signals output from sensors;

means for calculating correlation of phase variations between all pairs of sensors recorded in an assembly process, in frequency bands between 0 and 2000 Hz, to build up a database of classes each characterizing a reference state of cerebral electromagnetic activity of said individual;

means for statistically validating a period analyzed in real time to assign the period to a class in the database;

means for detecting a cognitive period or a specific pathological period; and

means for sending an alert signal if applicable.

12. A device according to claim 11, further comprising means for performing an analysis associated with at least one type of electrophysiological signals among electrocardiograms, electrooculograms, electrodermograms, breathing signals.

13. A device according to claim 11, wherein a PLS method is used by the means for statistically validating, which estimates a phase difference between oscillations of signals from two electrodes.

14. A device according to claim 13, wherein a statistical level of a PLS synchronization between two signals is evaluated using circular variance of the phase difference between the signals.

15. A device according to claim 13, wherein a statistical level of PLS synchronization between two signals is evaluated using normalized Shannon entropy of the phase difference between the signals.

16. A device according to claim 11, further comprising:

circuits for acquisition of signals representing electrical activity of the brain;

a processor configured for acquisition and processing of the signals; and

an alert circuit for the patient or for his/her environment.

17. A device according to claim 11, which is a device that the individual can carry himself or herself.

18. A device according to claim 11, miniaturized to be implanted subcutaneously.