A non-invasive ultra-high density EEG acquisition electrode

Abstract

The present invention discloses a non-invasive ultra-high density electroencephalogram (EEG) acquisition electrode, the structure of which comprises a hollow cylindrical electrode device (1) and a needle-shaped electrode device (2), wherein the needle-shaped electrode device (2) is mounted on the hollow cylindrical electrode device (1), and the needle-shaped electrode device (2) is a detachable combined structure that slides up and down relative to the hollow cylindrical electrode device (1). Compared with the prior art, the present invention greatly reduces the size of the non-invasive electroencephalogram (EEG) acquisition electrode, and can be used in the design of a non-invasive ultra-high density BCI system, reducing the electrode spacing to the millimeter level to improve the spatial resolution of the non-invasive electroencephalogram (EEG) signal; at the same time, the stability and ease of use of the non-invasive ultra-high density electroencephalogram (EEG) acquisition electrode when in use are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of brain-computer interface, and in particular to a non-invasive electroencephalogram (EEG) acquisition electrode. Background Art

[0002] Brain-Computer Interface (BCI) is a system that detects the activities of the central nervous system (CNS) and converts them into artificial output to replace, repair, enhance, supplement or improve the normal output of the CNS, thereby changing the continuous interaction between the CNS and its internal and external environment. Specifically, BCI can not only establish a connection pathway from the human brain to external devices to replace, repair or improve the patient's motor function impaired by injuries and diseases, and be used for peripheral control in a specific task environment, but also realize communication from the human brain to the machine and then to the human brain, thereby supplementing or enhancing the interaction between man and machine. The significance of BCI technology research lies in: first, it will greatly expand people's ability to communicate information with the outside world, which may trigger a revolution in traditional human external communication and control methods or channels; second, it will help to deeply understand the brain's cognitive patterns, information processes and control methods, and open up new research channels and methods for interpreting brain thinking models and consciousness formation mechanisms.

[0003] According to the placement of the detection signal sensor, BCI systems are divided into invasive and non-invasive types. The electrode density of the invasive BCI system is extremely high and it directly touches the neurons, avoiding the attenuation of the signal during the transmission process, so it has a high signal-to-noise ratio and good time, space and frequency resolution, and can achieve fine motor control and complete more complex tasks in three-dimensional space and real time. However, the invasive BCI system requires surgical implantation of electrodes, which will not only damage the brain tissue, but also maintain long-term biocompatibility. There are great risks and technical difficulties, and the application of invasive BCI technology is therefore limited. In addition, studies have shown that implanting electrodes in the motor cortex of the brain will cause neuronal damage and reduce motor function, mainly leading to impaired fine motor function.

[0004] Non-invasive BCI systems do not require surgical implantation of electrodes. They are easy to implement, safe, and portable, and are the focus of current research. However, the signals generated by the electrical activity of the cerebral cortex nerves are severely attenuated when they pass through tissue layers such as the skull to reach the surface of the scalp. In addition, due to the existence of the volume conductor effect, a large amount of information about the spatiotemporal distribution of the signal source of the electrical activity of the cerebral cortex nerves and the high-frequency components of the EEG are lost. This results in a low spatial resolution of non-invasive BCI EEG signals, making it difficult to effectively extract and accurately identify more delicate movement features such as finger movements. Therefore, the research on non-invasive BCI systems needs further breakthroughs, and the key lies in how to effectively improve the spatial resolution of scalp EEG.

[0005] Current research shows that for non-invasive BCI systems, when the electrode spacing is as low as the millimeter level, the non-invasive EEG spatial sampling frequency can be increased, the high-frequency components of the EEG signal can be obtained, and the spatial resolution of the non-invasive EEG can be improved. The electrode spacing of the traditional BCI system is more than 2 to 3 cm, and the high-density EEG electrode spacing can be as low as 1.4 cm, but it is still difficult to reach the millimeter level.

[0006] How to realize a new type of non-invasive ultra-high density EEG acquisition electrode that can improve the electrode density of the non-invasive BCI system is a technical problem that needs to be solved urgently in the present invention. Summary of the invention

[0007] In order to solve the problem that the existing non-invasive BCI system has low electrode density and is difficult to obtain high-frequency components and high spatial resolution information of EEG signals, the present invention proposes a non-invasive ultra-high density EEG acquisition electrode. By constructing a non-invasive ultra-high density brain-computer interface system, the spatial resolution of non-invasive EEG signals can be improved, and the electrode spacing can be reduced to millimeter level.

[0008] The technical solutions adopted by the present invention to solve the above problems are as follows:

[0009] A non-invasive ultra-high density EEG acquisition electrode, comprising a hollow cylindrical electrode device 1 and a needle-shaped electrode device 2, wherein the needle-shaped electrode device 2 is mounted on the hollow cylindrical electrode device 1, and the needle-shaped electrode device 2 is a detachable combined structure that slides up and down relative to the hollow cylindrical electrode device 1; wherein:

[0010] The hollow cylindrical electrode device 1 further comprises a hollow cylindrical electrode 11 and a translucent insulating tube 12, wherein the hollow cylindrical electrode 11 is embedded in the inner cavity of the translucent insulating tube 12;

[0011] The needle-shaped electrode device 2 also includes a needle-shaped electrode 21, a first insulating hollow cylinder 22, an insulating connection component 23, a second insulating hollow cylinder 24 and an electrode wire 25. The first insulating hollow cylinder 22 and the second insulating hollow cylinder 24 are respectively glued to the two ends of the insulating connection component 23, and the bottom surfaces of the first insulating hollow cylinder 22 and the second insulating hollow cylinder 24 are parallel; the diameter of the first insulating hollow cylinder 22 is smaller than the diameter of the second insulating hollow cylinder 24; one end of the needle-shaped electrode 21 is connected to the electrode wire 25 and glued to the inner cavity of the first insulating hollow cylinder 22, and the other end of the needle-shaped electrode 21 passes through the translucent insulating tube 12 in the inner cavity of the second insulating hollow cylinder 24 and is arranged parallel to the hollow cylindrical electrode 11.

[0012] The needle-shaped electrode 21 is a hollow structure, and the outer diameter of its cross section is 1 mm.

[0013] The overall maximum outer diameter of the non-invasive ultra-high density EEG acquisition electrode does not exceed 6 mm.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] The present invention greatly reduces the size of non-invasive EEG acquisition electrodes and can be used in the design of non-invasive ultra-high density BCI systems, reducing the electrode spacing to the millimeter level to improve the spatial resolution of non-invasive EEG signals; at the same time, it improves the stability and ease of use of non-invasive ultra-high density EEG acquisition electrodes when in use. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of a non-invasive ultra-high density EEG acquisition electrode of the present invention;

[0017] Figure 2 It is a front cross-sectional view of a non-invasive ultra-high density EEG acquisition electrode of the present invention;

[0018] Figure 3 It is a left schematic diagram of a non-invasive ultra-high density EEG acquisition electrode of the present invention;

[0019] Figure 4 It is a left-view structural cross-sectional diagram of a non-invasive ultra-high density EEG acquisition electrode of the present invention;

[0020] Figure 5 It is a schematic diagram of the main structure of the hollow cylindrical electrode device;

[0021] Figure 6 It is a schematic diagram of the top view of the structure of the hollow cylindrical electrode device;

[0022] Figure 7 It is a schematic diagram of the main structure of the needle-shaped electrode device;

[0023] Figure 8 This is a schematic diagram of the left view of the needle electrode device.

[0024] Reference numerals:

[0025] 1. Hollow cylindrical electrode device, 11. Hollow cylindrical electrode, 12. Translucent insulating tube;

[0026] 2. Needle-shaped electrode device, 21. Needle-shaped electrode, 22. First insulating hollow cylinder, 23. Insulating connecting component, 24. Second insulating hollow cylinder, 25. Electrode wire. DETAILED DESCRIPTION

[0027] The technical solution of the present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0028] Combination Figures 1 to 8 The specific structure of the present invention is as follows: the present invention comprises a hollow cylindrical electrode device 1 and a needle-shaped electrode device 2; wherein:

[0029] The hollow cylindrical electrode device 1 comprises a hollow cylindrical electrode 11 and a translucent insulating tube 12; wherein the hollow cylindrical electrode 11 is embedded in the inner cavity of the translucent insulating tube 12;

[0030] The needle-shaped electrode device 2 includes a needle-shaped electrode 21, a first insulating hollow cylinder 22, an insulating connection component 23, a second insulating hollow cylinder 24 and an electrode wire 25; wherein the outer wall of the first insulating hollow cylinder 22 is glued to the inner side of one end of the insulating connection component 23, and the bottom surface of the other end of the insulating connection component 23 is glued to the upper surface of the second insulating hollow cylinder 24. The bottom surfaces of the first insulating hollow cylinder 22 and the second insulating hollow cylinder 24 are parallel. The translucent insulating tube 12 is sleeved in the inner cavity of the second insulating hollow cylinder 24. One end of the needle-shaped electrode 21 is connected to the electrode wire 25 and glued to the inner cavity of the first insulating hollow cylinder 22, and the other end is suspended through the translucent insulating tube 12 in the inner cavity of the second insulating hollow cylinder 24, and is arranged parallel to the hollow cylindrical electrode 11.

[0031] The needle-shaped electrode device 2 is sleeved on the outside of the hollow cylindrical electrode device 1, and is suspended through the inner cavity of the hollow cylindrical electrode device 1. The needle-shaped electrode device 2 can slide up and down to adjust the position of the needle-shaped electrode.

[0032] Furthermore, the inner diameter of the second insulating hollow cylinder 24 is equal to the outer diameter of the translucent insulating tube 12 , and there is slight resistance when the needle-shaped electrode device 2 slides up and down relative to the hollow cylindrical electrode device 1 .

[0033] Furthermore, the hollow cylindrical electrode 11 is made of Ag / AgCl material.

[0034] Furthermore, the needle-shaped electrode 21 is made of Ag / AgCl material and is hollow in design, with an outer diameter of the cross section not greater than 1 mm;

[0035] Furthermore, the outer diameter of the first insulating hollow cylinder 22 is smaller than the inner diameter of the second insulating hollow cylinder 24 .

[0036] Furthermore, the maximum outer diameter of the overall structure of the non-invasive ultra-high density EEG acquisition electrode of the present invention is no more than 6 mm.

[0037] The needle electrode device and the hollow cylindrical electrode device are a combined structure and can slide relative to each other. The needle electrode is adjusted to make it fully contact with the user's scalp, thereby improving stability and facilitating the acquisition of stable EEG signals. The hollow cylindrical electrode and the hollow needle electrode fully increase the contact area between the conductive paste and the user's scalp and between the conductive paste and the needle electrode, further improving stability and facilitating the improvement of the signal-to-noise ratio of the EEG signal. The diameter of the first insulating hollow cylinder in the needle electrode device is smaller than that of the second insulating hollow cylinder. Such a structure facilitates the injection of the conductive paste, thereby improving the ease of use of the present invention.

[0038] The process of implementing EEG acquisition using a non-invasive ultra-high density EEG acquisition electrode of the present invention is as follows:

[0039] The hollow cylindrical electrode device 1 is fixed on the EEG cap, and the needle electrode device 2 is mounted on the hollow cylindrical electrode device 1. The lower end of the needle electrode 21 of the needle electrode device 2 is made to fully contact with the user's scalp through sliding adjustment. The other end of the electrode wire 25 is connected to the EEG amplifier to collect EEG signals.

Claims

1. A non-invasive ultra-high density EEG acquisition electrode, characterized in that: The non-invasive ultra-high density EEG acquisition electrode comprises a hollow cylindrical electrode device (1) and a needle-shaped electrode device (2), wherein the needle-shaped electrode device (2) is mounted on the hollow cylindrical electrode device (1), and the needle-shaped electrode device (2) is a detachable combined structure that slides up and down relative to the hollow cylindrical electrode device (1); wherein: The hollow cylindrical electrode device (1) further comprises a hollow cylindrical electrode (11) and a translucent insulating tube (12), wherein the hollow cylindrical electrode (11) is embedded in the inner cavity of the translucent insulating tube (12); The needle-shaped electrode device (2) further comprises a needle-shaped electrode (21), a first insulating hollow cylinder (22), an insulating connection component (23), a second insulating hollow cylinder (24) and an electrode wire (25); the first insulating hollow cylinder (22) and the second insulating hollow cylinder (24) are respectively glued to two ends of the insulating connection component (23), and the bottom surfaces of the first insulating hollow cylinder (22) and the second insulating hollow cylinder (24) are parallel; the translucent insulating tube (12) is sleeved in the inner cavity of the second insulating hollow cylinder (24); one end of the needle-shaped electrode (21) is connected to the electrode wire (25) and is glued to the inner cavity of the first insulating hollow cylinder (22); the other end of the needle-shaped electrode (21) passes through the translucent insulating tube (12) in the inner cavity of the second insulating hollow cylinder (24) and is arranged parallel to the hollow cylindrical electrode (11); the needle-shaped electrode (21) is a hollow structure, and the outer diameter of its cross section is 1 mm; The overall maximum outer diameter of the non-invasive ultra-high density EEG acquisition electrode does not exceed 6 mm.

2. A non-invasive ultra-high density EEG acquisition electrode as claimed in claim 1, characterized in that: The diameter of the first insulating hollow cylinder (22) is smaller than the diameter of the second insulating hollow cylinder (24).

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