A neural electrical signal acquisition and stimulation unit with elastic compensation mechanism

Abstract

The present invention relates to the field of brain electrodes, and specifically to a neural electrical signal acquisition and stimulation unit with an elastic compensation mechanism, the neural electrical signal acquisition and stimulation unit comprising: an electrode wire, an electrode terminal, a curing component and a shaping member, the shaping member being cured at the connection portion between the curing component and the electrode wire, and dissolving itself in the process of the electrode wire penetrating into the brain tissue, wherein the portion where the electrode wire is connected to the curing component forms a retractable elastic segment. The electrode wire provided by an embodiment of the present invention is provided with a retractable elastic segment, which retracts and contracts with the micro-movement of the brain tissue, so that the contact point between the elastic segment and the cerebral cortex remains unchanged, thereby making the implantation depth of the electrode wire implanted deep in the brain tissue remain unchanged, thereby solving the problem of relative movement between the electrode wire and the brain tissue, resulting in changes in the implantation depth of the electrode wire, shifting the implantation position, and affecting the accuracy of signal acquisition.

Description

Technical Field

[0001] The present invention relates to the field of brain electrodes, and in particular to a neural electrical signal acquisition and stimulation unit with an elastic compensation mechanism. Background Art

[0002] The basic principle of microwire electrodes is to use a fine electrode wire with an insulating layer, one end of which is connected to a back-end device with an amplifier, and the other end is directly inserted around the cell to transmit the weak current signal of the neuron to the back-end device for amplification and processing, thereby collecting the discharge signal of the neuron. Microwire electrodes can be used in combination with optical fibers and drug delivery tubes to expand their functions.

[0003] However, after the microwire electrode is implanted, one end is fixed to the skull surface and is in a static state, while the other end of the electrode wire can move with the micro-movement of the brain tissue. The relative movement between the electrode wire and the brain tissue can easily cause the implantation depth of the electrode wire to change, causing the implantation position to shift, affecting the accuracy of signal acquisition. Summary of the invention

[0004] The purpose of the present invention is to provide a neural electrical signal acquisition and stimulation unit with an elastic compensation mechanism to solve the problem that micro-movements of brain tissue cause relative movement between the electrode wire implanted in the brain tissue and the brain tissue, resulting in changes in the implantation depth of the electrode wire and shifting of the implantation position, affecting the accuracy of signal acquisition.

[0005] In order to solve the above technical problems, the present invention specifically provides the following technical solutions:

[0006] A neural electrical signal acquisition and stimulation unit with an elastic compensation mechanism, comprising: an electrode wire, which is used to be inserted into the brain tissue of an experimental subject; an insulating layer, which covers the surface of the electrode wire; an exposure point, which is formed at the end of the electrode wire, so that the end of the electrode wire is exposed outside the insulating layer to collect or transmit electrical signals; an electrode terminal, which electrically connects each of the electrode wires with a subsequent device and has an insulating layer on the surface; a curing component, which is cured at the connection between the electrode terminal and the electrode wire and is used to wrap and constrain the root of the electrode wire so that the adjacent electrode wires maintain a parallel posture to each other; a shaping member, which is cured at the electrode terminal; and a shaping member, which is cured at the electrode terminal. The connection part between the curing component and the electrode wire is used to wrap and constrain the electrode wire, so that the electrode wire maintains a predetermined shape during the insertion into the brain tissue, and dissolves itself during the process of the electrode wire penetrating into the brain tissue; wherein, the part where the electrode wire is connected to the curing component forms an elastic segment that can be stretched and retracted, one end of the elastic segment is connected to the curing component, and the other end is against the surface of the cerebral cortex, and the elastic segment has its own elastic force of extension, so that the elastic segment can adaptively stretch and retract with the micro-movement of the brain tissue through its own elasticity, so that the depth of the electrode wire implanted into the brain tissue remains unchanged;

[0007] The elastic section is designed to be spiral, wavy, broken line or spring-shaped;

[0008] The contact portion between the elastic segment and the cerebral cortex presents a fan-shaped ring with a central angle greater than 180 degrees; the end of the elastic segment away from the solidification component first moves along its own axis toward the solidification component, and then moves away from the solidification component, so that the portion where the electrode wire penetrates the cerebral cortex is in a straight state; the elastic segment constrained by the shaping member has an internal force to extend itself.

[0009] Furthermore, the electrode wires are arranged in a circular array or a rectangular array, and the curing assembly includes a head component, and the shape of the head component is set according to the arrangement of the electrode wires.

[0010] Furthermore, the material of the electrode wire is nickel-titanium alloy wire.

[0011] Furthermore, the insulating layer is formed of a flexible film material with biocompatibility.

[0012] Furthermore, the curing component is formed of a material having biocompatibility and stability.

[0013] Furthermore, the material of the shaping member is polyethylene glycol, collagen, chitosan, cellulose, polyamino acid, polylactic acid, polyglycolic acid, calcium phosphate, tricalcium phosphate, lactide, caprolactone, polyester or a mixture or copolymer thereof.

[0014] Compared with the prior art, this application has the following beneficial effects:

[0015] A neural electrical signal acquisition and stimulation unit with an elastic compensation mechanism is provided. The electrode wire provided in an embodiment of the present invention has an elastic segment that can be extended and retracted. The elastic segment extends and retracts along with the micro-movement of brain tissue, so that the contact point between the elastic segment and the cerebral cortex remains unchanged, thereby ensuring that the implantation depth of the electrode wire implanted deep in the brain tissue remains unchanged, thereby solving the problem of relative movement between the electrode wire and the brain tissue, resulting in changes in the implantation depth of the electrode wire and shifting of the implantation position, which affects the accuracy of signal acquisition. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0017] Figure 1is a perspective view of a first embodiment of the present invention;

[0018] Figure 2 A front view of an electrode wire according to a first embodiment of the present invention;

[0019] Figure 3 is a perspective view of a second embodiment of the present invention;

[0020] Figure 4 is a side view of a second embodiment of the present invention;

[0021] Figure 5 for Figure 4 Cross-sectional view in the AA direction;

[0022] The numbers in the figure represent the following:

[0023] 1-electrode wire; 11-elastic section; 2-curing assembly; 21-root component; 22-head component; 23-shell; 3-forming part; 4-electrode terminal. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] (First embodiment)

[0026] Figure 1 A stereogram of a multi-channel neural recording electrode is shown. Figure 1 As shown, the multi-channel neural recording electrode includes:

[0027] Electrode wire 1, used for inserting into the brain tissue of the experimental subject;

[0028] An insulating layer, covering the surface of the electrode wire 1, to ensure accurate signal conduction and biocompatibility;

[0029] The exposure point is formed at the tip of the electrode wire 1 so that it is exposed outside the insulating layer and can effectively collect or transmit electrical signals;

[0030] The electrode terminal 4 is used to connect each electrode wire 1 with the subsequent equipment, and an insulating layer is also provided on the surface to prevent signal interference;

[0031] The curing component 2 is cured at the connection portion between the electrode terminal 4 and the electrode wire 1, wrapping and constraining the root of the electrode wire 1, so that adjacent electrode wires 1 are arranged parallel to each other, thereby ensuring stability during the implantation process.

[0032] Specifically:

[0033] The curing assembly 2 includes a cubic root component 21, the electrode terminal 4 is embedded in the root component 21, and its plug portion is exposed outside the root component 21 so as to be connected to a subsequent device.

[0034] A head component 22 extends vertically from the center of the root component 21 , and one end of the electrode wire 1 passes through the head component 22 and the root component 21 and is connected to the electrode terminal 4 .

[0035] The outer wall of one end of the root component 21 away from the head component 22 is covered by a shell 23 to provide additional protection.

[0036] In order to enable the electrode wire to move with the micro-movement of the brain tissue and ensure that the implantation depth of the electrode wire remains unchanged when the brain tissue micro-moves, in this embodiment, the portion of the electrode wire connected to the head component 22 is designed to be spiral, wavy, broken line or spring-shaped to form an elastic segment 11. One end of the elastic segment 11 is connected to the head component 22, and the other end gently rests on the surface of the cerebral cortex. The elastic segment 11 has a self-stretching elastic force that can adapt to the tiny movements of the brain tissue. Through its own elastic expansion and contraction, it ensures that the depth of the electrode wire 1 implanted in the brain tissue remains stable.

[0037] Working principle of multi-channel neural recording electrodes:

[0038] The electrode wire 1 is inserted into the brain tissue of the subject, and the exposed point of the tip contacts the neuron. The electrode terminal 4 and the curing component 2 remain outside the subject.

[0039] After starting the subsequent device, the electrode wire 1 transmits the collected electrical signals to the subsequent device to record the neuronal activity; alternatively, the electrode wire 1 transmits the electrical signals generated by the subsequent device to the neurons to regulate the action potential of a single neuron and the field potential of a neuron group.

[0040] In order to prevent the elastic section 11 from being accidentally inserted into the cerebral cortex, which would cause the implantation depth of the electrode wire 1 to change, the elastic section 11 is designed to be spirally shaped to increase its contact area with the cerebral cortex.

[0041] At the same time, the end of the elastic section 11 away from the curing component 2 first moves slightly along its own axis toward the curing component 2 , then passes through the elastic section 11 horizontally, and then moves away from the curing component 2 .

[0042] This design makes the contact part between the elastic section 11 and the cerebral cortex form a fan-shaped ring with a central angle greater than 180 degrees, and the part where the electrode wire 1 penetrates the cerebral cortex is straight, thereby avoiding cutting of the cerebral cortex by the electrode wire 1.

[0043] The electrode wires 1 are arranged in a circular or rectangular array, and the shape of the head component 22 is designed according to the arrangement of the electrode wires 1: when the electrode wires 1 are arranged in a circular array, the head component 22 is cylindrical; when the electrode wires 1 are arranged in a rectangular array, the head component 22 is square columnar.

[0044] The tip of the electrode wire 1 can be flat or ground into a cone, and the bevel angles of all the tips are kept consistent and located on the same horizontal plane, thereby reducing damage to biological tissue when inserted into the brain tissue of the experimental subject.

[0045] The material of the electrode wire 1 is corrosion-resistant metal such as platinum, titanium, gold, platinum-iridium, tungsten or iridium oxide. It has good mechanical properties and conductivity, is not easy to break during the puncture process, and has high biocompatibility, which reduces the stimulation and toxicity to biological tissues and realizes continuous, long-term and efficient physiological electrical signal acquisition and transmission.

[0046] Among them, nickel-titanium alloy wire with a diameter of 5-100 microns is preferably used. Nickel-titanium alloy wire has shape memory function and superelasticity, good biocompatibility, and little damage to body tissues.

[0047] The insulating layer is made of flexible materials, including polyimide (PI), Parylene, polydimethylsiloxane (PDMS), polyurethane (PU), silicone, silicone rubber and other biocompatible flexible film materials.

[0048] There are two methods for forming the exposure point: one is to expose the tip of the electrode wire 1 by cutting or grinding it after the insulating layer covers the electrode wire 1; the other is to pre-shield the tip of the electrode wire 1 before the insulating layer covers it to prevent it from being covered by the insulating layer, so that the electrode wire 1 can accurately collect the electrical signals of the designated neurons and avoid interfering with non-target neurons.

[0049] The curing component 2 can be made of medical-grade, non-degradable materials such as silicone or polyimide to ensure structural stability and biosafety.

[0050] (Second embodiment)

[0051] Since the electrode wire 1 is thin and soft, it is generally only suitable for recording in the cerebral cortex and is not suitable for recording in deep brain regions. In particular, after the elastic section 11 is formed at the root of the electrode wire 1, it is more difficult to implant it in deep brain regions. In order to solve this problem, a second embodiment is proposed.

[0052] Figure 3 A stereogram showing a multi-channel neural recording electrode. Figure 4 For its side view, Figure 5 for Figure 4 Cross-sectional view along the AA direction.

[0053] like Figures 3 to 5 As shown, the multi-channel neural recording electrode is based on the first embodiment and has an additional shaping member 3.

[0054] The shaping member 3 is a material that can be cured at low temperature, and is cured at the connection between the curing component 2 and the electrode wire 1, and is used to wrap and restrict the movement of the electrode wire 1 so that it maintains a predetermined shape during insertion into the experimental body.

[0055] The shaping member 3 has the property of being soluble in water. As the electrode wire 1 gradually penetrates into the brain tissue, the shaping member 3 will dissolve by itself. The electrode wire 1 located inside the brain tissue advances along the puncture channel formed by itself in the brain tissue to ensure the stability of the puncture direction. The electrode wire 1 located outside the brain tissue is still wrapped and constrained by the shaping member 3 to prevent it from deforming. Finally, the electrode wire 1 vertically penetrates into the target brain area, the shaping member 3 completely dissolves, and only the electrode wire 1 remains in the brain tissue.

[0056] The shaping member 3 can be made of materials that can be metabolized by the experimental subject, such as collagen, chitosan, cellulose, polyethylene glycol, polyamino acid, polylactic acid, polyglycolic acid, calcium phosphate, tricalcium phosphate, lactide, glycolide, caprolactone, polyester or mixtures or copolymers of the above materials.

[0057] Among them, polyethylene glycol is preferably used as the material of the shaping member 3 because of its good biocompatibility and non-toxic and side effects of degradation products.

[0058] Before using the shaping member 3 to wrap the electrode wire 1, a slight external force is first applied to the elastic segment 11 of the electrode wire 1 to make the elastic segment 11 slightly shrink for a distance, and then the shaping member 3 is used to constrain the shape of the electrode wire 1. With this design, when the shaping member 3 degrades, the elastic segment 11 immediately generates a stretching elastic force, so that the tip of the electrode wire 1 further penetrates into the target brain area, or ensures the stability of the implantation depth.

[0059] Through the above design, the multi-channel neural recording electrode can effectively adapt to the tiny movements of brain tissue, keep the implantation depth of the electrode wire 1 unchanged, reduce damage to brain tissue, and improve the accuracy and stability of neural signal acquisition. In particular, the shaping piece 3 introduced in the second embodiment enables the electrode wire 1 to be smoothly implanted into deep brain areas, broadening the application range of the electrode. This design has important application value in the fields of neuroscience research, clinical neural regulation, and brain-computer interface, and can provide efficient and reliable technical means for the research and treatment of related diseases.

[0060] The above embodiments are only exemplary embodiments of the present invention and are not intended to limit the present invention. The protection scope of the present invention is defined by the claims. Those skilled in the art may make various modifications or equivalent substitutions to the present invention within the essence and protection scope of the present invention, and such modifications or equivalent substitutions shall also be regarded as embodiments of the present invention and fall within the protection scope of the present invention.

Claims

1. A neural electrical signal acquisition and stimulation unit with an elastic compensation mechanism, characterized in that: include: Electrode wire, used to insert into the brain tissue of the experimental subject; An insulating layer covering the surface of the electrode wire; An exposure point is formed at the end of the electrode wire, so that the end of the electrode wire is exposed outside the insulating layer to collect or transmit electrical signals; Electrode terminals, electrically connecting each of the electrode wires with the subsequent equipment, and having an insulating layer on the surface; A curing assembly, cured at the connection portion between the electrode terminal and the electrode wire, for wrapping and restraining the root of the electrode wire so that the adjacent electrode wires maintain a posture parallel to each other; a shaping member, solidified at the connection portion between the solidification component and the electrode wire, used to wrap and constrain the electrode wire so that the electrode wire maintains a predetermined shape during insertion into the brain tissue, and dissolves itself during the process of the electrode wire penetrating into the brain tissue; in, The portion where the electrode wire is connected to the curing component forms an elastic segment that can be stretched and retracted, one end of the elastic segment is connected to the curing component, and the other end is against the surface of the cerebral cortex. The elastic segment has its own elastic force of extension, so that the elastic segment can adaptively stretch and retract with the micro-movement of the brain tissue through its own elasticity, so that the depth of the electrode wire implanted into the brain tissue remains unchanged; The elastic section is designed to be spiral, wavy, broken line or spring-shaped; The contact portion between the elastic segment and the cerebral cortex presents a fan-shaped ring with a central angle greater than 180 degrees; The end of the elastic section away from the curing component first moves along its own axis toward the curing component, and then moves away from the curing component, so that the portion where the electrode wire penetrates the cerebral cortex is in a straight state; The elastic section constrained by the shaping member has an internal force to extend itself.

2. A neural electrical signal acquisition and stimulation unit with an elastic compensation mechanism according to claim 1, characterized in that: The electrode wires are arranged in a circular array or a rectangular array, and the curing assembly includes a head component, and the shape of the head component is set according to the arrangement of the electrode wires.

3. A neural electrical signal acquisition and stimulation unit with an elastic compensation mechanism according to claim 1, characterized in that: The material of the electrode wire is nickel-titanium alloy wire.

4. A neural electrical signal acquisition and stimulation unit with an elastic compensation mechanism according to claim 1, characterized in that: The insulating layer is formed of a flexible film material with biocompatibility.

5. The neural electrical signal acquisition and stimulation unit with elastic compensation mechanism according to claim 1, characterized in that: The curing component is formed of a material having biocompatibility and stability.

6. A neural electrical signal acquisition and stimulation unit with an elastic compensation mechanism according to claim 1, characterized in that: The material of the shaping member is polyethylene glycol, collagen, chitosan, cellulose, polyamino acid, polylactic acid, polyglycolic acid, calcium phosphate, tricalcium phosphate, lactide, caprolactone, polyester or a mixture or copolymer thereof.

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