PHASE AND STATE DEPENDENT EEG AND BRAIN IMAGING

• US 20090062676A1
• Filed: 05/06/2004
• Published: 03/05/2009
• Est. Priority Date: 05/06/2003
• Status: Abandoned Application

• Current Assignee: George Mason Intellectual Properties, Inc.
• Original Assignee: George Mason Intellectual Properties, Inc.
• Inventors: Schiff, Steven, Kruglikov, Stepan
• Application Number:
  US10/555,794
• Publication Number:
  US 20090062676A1
• Time in Patent Office: Days
• US Class Current: 600/544
• CPC Class Codes: A61B 5/377 using evoked responses
• CPC Class Codes: A61B 5/378 Visual stimuli
• CPC Class Codes: A61B 5/38 Acoustic or auditory stimuli
• CPC Class Codes: A61B 5/381 Olfactory or gustatory stimuli
• CPC Class Codes: A61B 5/726 using Wavelet transforms
• CPC Class Codes: A61B 5/7285 for synchronising or triggering a physiological measurement or image acquisition with a physiological event or waveform, e.g. an ECG signal A61B6/5205, A61B6/541, A61B8/5207, A61B8/543 take precedence
• CPC Class Codes: A61B 6/541 involving acquisition triggered by a physiological signal
• CPC Class Codes: A61B 8/543 involving acquisition triggered by a physiological signal
• CPC Class Codes: G16H 50/70 for mining of medical data, e.g. analysing previous cases of other patients

Abstract

The present invention provides methods and devices for performing electroencephalographic (EEG) phase dependent brain imaging using evoked and event related potentials (EP, ERP) or other forms of brain imaging including functional magnetic resonance imaging (fMRI) and magnetic encephalography (MEG). The methods and devices can be used for a variety of purposes, including for the study of normal and pathological cognitive function, and for the diagnosis and prognosis of neurological and sleep disorders.

Claims

1. A method for determining the EEG phase of a subject, comprising,

recording an EEG from a subject'"'"'s brain, and

calculating a voltage amplitude threshold value from the EEG, whereby said threshold value corresponds to a value of phase of said EEG.

2. A method of claim 1, wherein said amplitude threshold is calculated retrospectively.

3. A method of claim 1, wherein said value of phase of said EEG is further calculated by Hilbert or wavelet transformation.

4. A method of claim 1, wherein said amplitude threshold is calculated in real time.

5. A method of claim 1, further comprising,

wherein the value of said EEG phase is assigned at a timed delay from the voltage amplitude threshold value.

6. A method of claim 1, wherein the voltage amplitude threshold value is the most negative 0.5% or less of the distribution of amplitudes measured from said EEG

7. A method of claim 1, wherein the voltage amplitude threshold value is the most negative 1% or less of the distribution of amplitudes measured from said EEG.

8. A method of claim 1, wherein the voltage amplitude threshold value is the most negative 5% or less of the distribution of amplitudes measured from said EEG.

9. A method of claim 1, wherein the voltage amplitude threshold value is the most positive 0.5% or greater of the distribution of amplitudes measured from said EEG.

10. A method of claim 1, wherein the voltage amplitude threshold value is the most positive 1% or greater of the distribution of amplitudes measured from said EEG.

11. A method of claim 1, wherein the voltage amplitude threshold value is the most positive 5% or greater of the distribution of amplitudes measured from said EEG.

21. A method of imaging the brain of a subject, comprising, collecting a plurality of images of a brain at defined phases of an EEG according to claim 1.

22. A method of claim 21, wherein said image is acquired using electrode arrays as EEG, magnetic encephalography (MEG), magnetic resonance imaging, functional magnetic resonance imaging, positron emission tomography, fluoro-deoxyglucose positron emission tomography, single photon emission tomography.

23. A method of claim 21, wherein said image is acquired using optical imaging.

24. A method of claim 23, wherein said optical imaging uses a near infrared imaging, an intrinsic optical signal, or an absorption or fluorescent optical dye.

12. A method for determining the phase of a subject'"'"'s brain with respect to a magnetic encephalography (MEG), or functional magnetic resonance (fMRI) signal, comprising:

recording a MEG or fMRI signal from a subject'"'"'s brain, and

calculating a signal amplitude threshold value from the MEG or fMRI recording, whereby said threshold value corresponds to a value of phase.

13. A method of detecting and recording an evoked potential of a stimulus, comprising,

recording an EEG in the presence and absence of a stimulus, wherein the stimulus is triggered at a defined position in the EEG phase,

aligning, in phase, (a) a segment of the EEG recorded in the absence of the stimulus with (b) a segment of the EEG recorded in the presence of the stimulus, and

subtracting (a) the EEG record in the absence of the stimulus from (b) the EEG record in the presence of the stimulus,

whereby the net difference between (a) and (b) is the evoked potential of said stimulus, and wherein the records are aligned in phase when subtracted.

14. A method of claim 13, wherein said stimulus is an auditory, visual, electrical, magnetic, mechanical, thermal, olfactory, or taste stimulus.

15. A method of claim 14, wherein said mechanical stimulus is a touch, pressure, vibration, or joint movement stimulus.

16. A method of claim 13, wherein said comparison is performed for single or multiple channel EEG.

17-20. -20. (canceled)

25-26. -26. (canceled)