Headset for bio-signals acquisition

Abstract

Disclosed is an audio-headset for acquisition of a bio-signal from a subject, including a first earpiece; a second earpiece; an arch connecting the first earpiece and the second earpiece; the arch including a hub (4); wherein the arch, the first earpiece and the second earpiece are configured so that the earpieces are placed over a subject's ears when the audio headset is worn by the subject; and at least one posterior branch (1) having a first end extending from the hub and a second free end; the at least one posterior branch (1) including a concave surface with a radius of curvature, a collapsed state when the headset is not worn by the subject and an expanded state when the headset is worn by the subject.

Claims

1. An audio-headset for acquisition of a bio-signal from a subject, comprising: a first earpiece and a second earpiece; an arch connecting the first earpiece and the second earpiece, said arch comprising a hub, wherein the arch, the first earpiece and the second earpiece are configured so that the earpieces are placed over a subject's ears when the audio headset is worn by the subject; and at least one posterior branch having a first end extending from the hub and a second free end, wherein, the at least one posterior branch comprises at least one electrode configured for acquiring a bio-signal, the at least one posterior branch comprises a concave surface with a radius of curvature, a collapsed state when the audio headset is not worn by the subject and an expanded state when the audio headset is worn by the subject; wherein the ratio between the radius of curvature in the expanded state and the radius of curvature in the collapsed state is higher than 2.36, and the at least one electrode of the at least one posterior branch comprises at least two pins, each pin having a first free end comprising a skin-contact interface and a second end connected to at least one flexure element, and the first earpiece and the second earpiece comprise each at least one textile electrode, the earpieces and the arch being configured such that the textile electrodes rest against the skin disposed over the mastoid processes when the audio-headset is worn by the subject.

2. The audio-headset according to claim 1, wherein the at least one posterior branch comprises at least one electrode configured for acquiring a bio-signal at position P3 or P4 in a 10-10 system.

3. The audio-headset according to claim 1, wherein the audio-headset comprises at least two posterior branches.

4. The audio-headset according to claim 3, wherein the first posterior branch is configured for acquiring a bio-signal at position P3 in a 10-10 system and the second posterior branch is configured for acquiring a bio-signal at position P4 in the 10-10 system.

5. The audio-headset according to claim 1, wherein the at least one posterior branch is releasably connected to the hub.

6. The audio-headset according to claim 1, wherein the first earpiece and the second earpiece are circumaural earpieces.

7. The audio-headset according to claim 1, wherein the at least one electrode of the first earpiece and the at least one electrode of the second earpieces are fabric electrodes.

8. The audio-headset according to claim 1, wherein the at least one electrode of the first earpiece and the at least one electrode of the second earpieces comprises an argent coated textile.

9. The audio-headset according to claim 1, wherein the at least one electrode of the first earpiece and the at least one electrode of the second earpieces comprise a plurality of contact surfaces.

10. The audio-headset according to claim 1, the at least one electrode of the first earpiece and the at least one electrode of the second earpieces comprise a common part from which extends a plurality of strips; and wherein the common part is embedded within the earpiece and at least part of the strips are located on the outer surface of the earpiece.

11. The audio-headset according to claim 1, wherein the at least one posterior branch comprises an amagnetic metal sheet.

12. The audio-headset according to claim 1, wherein the electrodes of the audio-headset comprise a ground electrode, a reference electrode, and at least one acquisition electrode.

13. The audio-headset according to claim 1, wherein the electrodes of the audio-headset are configured to carry out an electroencephalography, and/or electromyography, electrooculography or electrocardiography.

14. The audio-headset according to claim 1, being further connected to a bio-signal processor for analyzing and interpreting the measured bio-signal.

15. An audio-headset for acquisition of a bio-signal from a subject, comprising: a first earpiece; a second earpiece; an arch connecting the first earpiece and the second earpiece, said arch comprising a hub, wherein the arch, the first earpiece and the second earpiece are configured so that the earpieces are placed over a subject's ears when the audio headset is worn by the subject; and at least one anterior branch having a first end extending from the hub and a second free end, wherein, the at least one anterior branch comprises at least one electrode configured for acquiring a bio-signal, the at least one anterior branch comprises a concave surface with a radius of curvature, a collapsed state when the audio headset is not worn by the subject and an expanded state when the audio headset is worn by the subject; wherein the ratio between the radius of curvature in the expanded state and the radius of curvature in the collapsed state is higher than 2.10, and the at least one electrode of the at least one anterior branch comprises at least two pins, each pin having a first free end comprising a skin-contact interface and a second end connected to at least one flexure element, and the first earpiece and the second earpiece comprise each at least one textile electrode, the earpieces and the arch being configured such that the textile electrodes rest against the skin disposed over the mastoid processes when the audio-headset is worn by the subject.

16. The audio-headset according to claim 15, wherein the at least one anterior branch comprises at least one electrode configured for acquiring a bio-signal at position AF3 or AF4 in a 10-10 system.

17. The audio-headset according to claim 15, comprising at least two anterior branches wherein the electrodes comprised in the two anterior branches are disposed so that the first anterior branch is configured for acquiring a bio-signal at position AF3 in a 10-10 system and the second anterior branch is configured for acquiring a bio-signal at position AF4 in the 10-10 system.

18. The audio-headset according to anyone of claim 15, wherein the at least one anterior branch is releasably connected to the hub.

19. A method for providing neurofeedback to at least one subject, the method comprising the following steps: placing on the top of the head of a subject an audio-headset for bio-signal acquisition, the headset comprising: a first earpiece and a second earpiece; an arch connecting the first earpiece and the second earpiece, said arch comprising a hub, wherein the arch, the first earpiece and the second earpiece are configured so that the earpieces are placed over a subject's ears when the audio headset is worn by the subject; and at least one posterior branch having a first end extending from the hub and a second free end, wherein, the at least one posterior branch comprises at least one electrode configured for acquiring a bio-signal, the at least one posterior branch comprises a concave surface with a radius of curvature, a collapsed state when the audio headset is not worn by the subject and an expanded state when the audio headset is worn by the subject; wherein the ratio between the radius of curvature in the expanded state and the radius of curvature in the collapsed state is higher than 2.36, and the at least one electrode of the at least one posterior branch comprises at least two pins, each pin having a first free end comprising a skin-contact interface and a second end connected to at least one flexure element, and the first earpiece and the second earpiece comprise each at least one textile electrode, the earpieces and the arch being configured such that the textile electrodes rest against the skin disposed over the mastoid processes when the audio-headset is worn by the subject; acquiring a bio-signal using the headset; analyzing the acquired bio-signal; and providing an audio-feedback to said subject in accordance with the measured bio-signal.

20. The method for providing neurofeedback according to claim 19, wherein the analysis of the bio-signal comprises the step of correlating the bio-signal with a specific mental state and providing the subject with a feedback comprising at least one suggestion for improving the subject mental state.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic representation of a headset comprising at least 3 flexible branches (1, 2, 3) in an expanded configuration.

(2) FIG. 2 is a schematic representation of a headset comprising at least 3 flexible branches (1, 2, 3) in a collapsed configuration and an expanded configuration.

(3) FIG. 3 is a schematic representation of a headset with 4 flexible branches (1r, 1l, 2, 3) for bio-signal acquisition in an expanded configuration.

(4) FIG. 4 is a schematic representation of a headset with 4 flexible branches (1r, 1l, 2, 3) for bio-signal acquisition in situ, positioned on a head in an expanded configuration.

(5) FIG. 5 is a schematic representation of the headset with 4 flexible branches (1r, 1l, 2, 3) for bio-signal acquisition in an expanded configuration.

(6) FIG. 6 is a schematic representation of the headset with 4 flexible branches (1r, 1l, 2, 3) for bio-signal acquisition in situ, positioned on a head in an expanded configuration.

(7) FIG. 7 is a schematic representation of the headset with 6 flexible branches for bio-signal acquisition in an expanded configuration.

(8) FIG. 8 is a schematic representation of an electrode (5) comprising spring loaded pins (6) plunged on a matrix setting (10).

(9) FIG. 9 is a schematic representation of the electronic devices integrated in the headset.

(10) FIG. 10 is a graph representing the evolution of the PSD (Power Spectral DensityDecibel/Hertz) according to the frequency (Hz).

(11) FIG. 11 is a schematic representation of an audio-headset according to one embodiment of the invention in the collapsed configuration.

(12) FIG. 12 is a schematic representation of an audio-headset with, for the purpose of illustration, one posterior branch in the expanded configuration (1) and one posterior branch is the collapsed configuration (1).

(13) FIG. 13 is a schematic illustration of the Morphological Overlapping Spheres (MOS) method.

(14) FIG. 14 is a schematic representation of the radius of curvature of a branch in a collapsed state (CRc) and in an expanded state (CRe). The rectangle illustrates the hub (4). The point in contact with the hub illustrates the first end of the branch. Fill (respectively dot) line illustrates the branch at the collapsed configuration (respectively expanded configuration). The points at the free end of each branch represent the electrodes positioning. Circles are the sections of the spheres defining the curvature radius of each branch. The arrow on the hub displays the movement the subject is applying to position the headset and thus the extension of the branch from the collapsed configuration to the expanded configuration.

(15) FIG. 15 illustrates the connection between the hub and the branch of the audio-headset of the invention.

(16) FIG. 16 illustrates an EEG time frequency map for EO-EC showing alpha blocking detection; the signal has been recorded with textile electrodes.

(17) FIG. 17 illustrates a textile electrode according to one embodiment of the invention.

(18) FIG. 18 illustrates an earpiece comprising a textile electrode according to one embodiment of the invention.

REFERENCES

(19) 1Acquisition flexible branch (in the expanded state)

(20) 1Acquisition flexible branch (in the collapsed state)

(21) 1rRight acquisition flexible branch

(22) 1lLeft acquisition flexible branch

(23) 1aFirst end of the acquisition flexible branch

(24) 1bFree end of the acquisition flexible branch

(25) 1lAnterior flexible branch

(26) 11rRight anterior flexible branch

(27) 11lLeft anterior flexible branch

(28) 12Posterior flexible branch

(29) 12rRight posterior flexible branch

(30) 12lLeft posterior flexible branch

(31) 2Left peripheral branch (in the expanded state)

(32) 2Left peripheral branch (in the collapsed state)

(33) 2aFirst end of the left peripheral branch

(34) 2bFree end of the left peripheral branch

(35) 3Right peripheral branch

(36) 3aFirst end of the right peripheral branch

(37) 3bFree end of the right peripheral branch

(38) 4Hub

(39) 5Electrodes

(40) 51Common part of a textile electrode

(41) 52Strips of a textile electrode

(42) 53Connecting cable connecting the textile electrode to the PCB

(43) 6Pins

(44) 7Flexure element

(45) 8Skin contact interface

(46) 9Circuit contact interface

(47) 10Matrix setting

(48) 13Electronic circuit

(49) 14Earpiece

(50) 15Arch

(51) 16Audio-headset

(52) 17Flexible blade

(53) , Load angles

EXAMPLES

(54) The present invention is further illustrated by the following example.

Example 1

(55) This example shows the results of Steady State Visually Evoked Potentials (SSVEP).

(56) EEG bio-signals were recorded during visual stimulations at the scalp location Oz using the headset according to the present invention. The visual stimulation was composed by chessboard flashing at the specific frequency of 30 Hz. A recording session at rest was also done in order to compare the results at the same location without visual stimulations. FIG. 10 shows the Power Spectral Density (PSD) of one minute recording. We can see that the PSD increases at 30 Hz (and also its harmonic at 60 Hz) directly related to the SSVEP. From our analysis, the peak amplitude at 30 Hz reaches twice time the PSD level at 30 Hz in resting state condition using only 3s of buffer acquisition. This ratio reaches five times using 15s of buffer acquisition and ten times using one minute of buffer acquisition.

Example 2

(57) FIG. 16 illustrates a time-frequency map (computation based on Morlet wavelet) of an EEG recording during an eyes closed condition. It is well known from the very beginning of EEG that eyes closed condition versus eyes opened condition shows alpha blocking. This figure displays on x-axis the time of recording and the PSD on y-axis. We can see clearly strong alpha (8-12 Hz) power increasing all over the recording.