CN222510401U - Electrode and device for implantable brain-computer interface - Google Patents

Abstract

The utility model relates to the technical field of brain-computer interfaces, and discloses an electrode for an implantable brain-computer interface and a device thereof, which aim to optimize contact with cerebral cortex so as to capture nerve electrical activity efficiently and safely. The electrode design includes an elastomeric polymeric layer, a first coating, a metallic layer, and a second coating, forming two morphological structures with different mechanical properties. The first form provides the required mechanical strength through the combination of the metal layer and the first coating layer, and is suitable for stable implantation, while the second form enhances flexibility through the arrangement of the elastic polymeric layer and the second coating layer, and reduces damage to brain tissues. The unique bimodal design enables the electrodes to minimize the invasion of brain tissues while ensuring the signal transmission efficiency, and opens up new possibilities for the application of brain-computer interface technology.

Description

Electrode and device for implantable brain-computer interface

Technical Field

The utility model belongs to the field of brain-computer interfaces, and particularly relates to an electrode and a device for an implantable brain-computer interface.

Background

Implantable brain-computer interfaces employing cortical electrodes have several advantages over using non-invasive EEG and invasive deep electrode brain-computer interfaces, including higher spatial resolution, more stable and reliable recording, and no need for invasive surgical procedures. Implantable brain-computer interfaces based on cortical electrodes have been shown to have great potential for improving the life of disabled people, promoting neurological recovery, and developing new human-computer interaction modalities.

Currently, semi-invasive cortical electrodes, such as foreign PMT, ad-Tech, domestic Hua Keheng green electrodes, etc., are used clinically, typically using stainless steel or platinum iridium alloy as the electrode contact material, welded individually to separate wires, and wrapped with about 1: 1 mm thick silica gel as the insulating layer. These electrode contacts are typically 2.3 mm a in diameter, 1 a cm a pitch, a linear strip electrode of 2 to 8 contacts or an array sheet electrode of 8-32 contacts. In clinical applications, these electrodes may be bent to cover the cortical region of interest. However, the effective bending rigidity of the ECoG electrode is higher due to the hard metal part and thicker silica gel, and adverse reactions such as poor contact between the electrode contact and the cortex, moving contact positions, insufficient space precision, inflammation and the like can occur in practical application, so that the application of the ECoG electrode in brain-computer interfaces is limited.

In order to solve the above problems, a common method is to process electrodes on flexible polymer substrates based on polyimide and parylene C using a micro-nano process. However, since such flexible materials have a high young's modulus, the thickness of the electrode to be flexibly bonded is generally thin (several to several tens micrometers), and curling easily occurs after releasing from the substrate, and surgical implantation is inconvenient when the coverage area is large. Elastic polymers such as silica gel are also a commonly used substrate material, which has high transparency and young's modulus comparable to that of brain, and can achieve great improvement of combination and biocompatibility with two-photon technology. The silica gel can maintain smaller bending rigidity at the thickness of 100 to 200 micrometers because the Young modulus is closer to brain tissue, but has poorer compatibility with micro-nano processing technology when being directly used as a base material because the thermal expansion coefficient of the silica gel is larger.

Disclosure of Invention

In view of this, the embodiment of the utility model provides an electrode and a device for an implantable brain-computer interface, which mainly aims to improve micro-nano machining compatibility of the electrode under the conditions of improving mechanical strength and soft attaching performance of the electrode, and to improve line density of the electrode machining by utilizing high precision of a micro-nano process to a greater extent, so as to provide higher spatial precision for data acquisition of the brain-computer interface.

In order to achieve the above purpose, the present utility model mainly provides the following technical solutions:

In one aspect, the embodiment of the utility model provides an electrode for an implantable brain-computer interface, wherein a part of the electrode is in contact with a cerebral cortex of a living being and is used for acquiring brain electrical signals, the electrode at least comprises an elastic polymer layer, a first coating, a metal layer and a second coating, the first coating and the metal layer belong to a first form, the elastic polymer layer and the second coating belong to a second form, and the first form and the second form are different.

Optionally, the elastic polymeric layer, the first coating, the metal layer and the second coating are stacked in sequence, an intermediate layer is formed after the first coating and the metal layer are combined with each other, a wrapping layer is formed after the elastic polymeric layer and the second coating are combined with each other, and the intermediate layer is arranged in the wrapping layer.

Optionally, the electrode further comprises a conductive polymer layer and a third coating, wherein the conductive polymer layer is arranged above the second coating, and the third coating is arranged below the elastic polymer layer and is attached to the elastic polymer layer.

Optionally, the first surface of the second coating layer is provided with a through hole, and the conductive polymer layer is attached to the metal layer through the through hole.

Optionally, the metal layer at least comprises an adhesion metal layer, a conductive layer and a metal protection layer, wherein the adhesion metal layer, the conductive layer and the metal protection layer are sequentially stacked, the adhesion metal layer is attached to the first coating, and the metal protection layer is attached to the second coating.

Optionally, the edge of the first coating is attached to the edge of the metal layer, the edge of the elastic polymeric layer is attached to the edge of the second coating, and the surface area of the elastic polymeric layer and the second coating is larger than the surface area of the first coating and the metal layer.

Optionally, the electrode comprises a detection part, a transmission part and an interface part, wherein the detection part, the transmission part and the interface part are integrally formed.

Optionally, the detection part is rectangular, the transmission part is in a shape of a line, and the interface part is rectangular, wherein the detection part is connected with the transmission part, and the transmission part is connected with the interface part.

Optionally, the first shape is a first shape, and the second shape is a second shape, wherein the first shape is different from the second shape;

On the other hand, the embodiment of the utility model provides a device for an implantable brain-computer interface, which comprises the electrode, wherein the electrode is connected with external equipment, the external equipment comprises a signal conversion part and a data analysis part, the signal conversion part is used for converting data between a digital signal and an analog signal, and the data analysis part is used for analyzing and processing the brain electrical signal so as to acquire brain data.

The electrode for the implantable brain-computer interface and the device thereof provided by the embodiment of the utility model are characterized in that one part of the electrode is contacted with a biological cerebral cortex for acquiring brain electrical signals, and then the brain electrical signals are transmitted to external equipment and then decoded and analyzed. The electrode at least comprises an elastic polymeric layer, a first coating, a metal layer and a second coating, and forms two morphological structures with different mechanical properties. The first form provides the required mechanical strength through the combination of the metal layer and the first coating layer, and is suitable for stable implantation, while the second form enhances flexibility through the arrangement of the elastic polymeric layer and the second coating layer, and reduces damage to brain tissues. The unique bimodal design enables the electrodes to minimize the invasion of brain tissues while ensuring the signal transmission efficiency, and opens up new possibilities for the application of brain-computer interface technology.

Drawings

Fig. 1 is a schematic diagram of an overall structure of an electrode according to an embodiment of the present utility model.

Fig. 2 is a schematic view of another angle of an electrode according to an embodiment of the present utility model.

Fig. 3 is a schematic diagram of a metal layer structure of an electrode according to an embodiment of the present utility model.

Fig. 4 is a schematic diagram of electrode area division according to an embodiment of the present utility model.

Reference numerals 10, electrode, 11, third coating, 12, elastic polymer layer, 13, first coating, 14, metal layer, 15, second coating, 16, conductive polymer layer, 101, detection part, 102, transmission part, 103, interface part, 141, metal protection layer, 142, conductive layer, 143, adhesion metal layer

Detailed Description

In order to further describe the technical means and effects adopted by the utility model to achieve the preset aim, the specific implementation, structure, characteristics and effects of the electrode of the implantable brain-computer interface according to the utility model are described in detail below with reference to the accompanying drawings and the preferred embodiments. In the following description, different "an embodiment" or "an embodiment" do not necessarily refer to the same embodiment. Furthermore, the particular features, structures, or characteristics of one or more embodiments may be combined in any suitable manner.

As shown in fig. 1 and 2, an electrode 10 for an implantable brain-computer interface according to an embodiment of the present utility model includes at least an elastic polymer layer 12, a first coating layer 13, a metal layer 14, a second coating layer 15, and a conductive polymer layer 16, where the elastic polymer layer 12 is disposed at the bottommost layer of the electrode 10, and the conductive polymer layer 16 is disposed at the topmost layer of the electrode 10, and at the same time, the conductive polymer layer 16 is bonded to the cerebral cortex of a living being, so that the electrode 10 performs electrical signal acquisition on the cerebral cortex of the living being, that is, a portion of the electrode 10 is in contact with the cerebral cortex of the living being, that is, the conductive polymer layer 16 is in contact with the cerebral cortex of the living being, specifically, the detection portion 101 of the conductive polymer layer 12 is bonded to the cerebral cortex of the living being, and at the same time, the conductive polymer layer 16 only partially blocks the second coating layer 15, so that the partial region of the second coating layer 15 not blocked by the conductive polymer layer 16 is also bonded to the cerebral cortex of the living being, that is, the detection portion 101 of the second coating layer 15 and the structural surface of the transmission portion 102 are bonded to the cerebral cortex of the living being. The first coating layer 13 is arranged above the elastic polymeric layer 12 for adhesion so that the elastic polymeric layer 12 is bonded to the metal layer 14, the metal layer 14 is arranged above the first coating layer 13 for capturing and transmitting bioelectrical signals, and the second coating layer 15 is arranged above the metal layer 14 for adhesion so that the metal layer 14 is bonded to other structures on the one hand and for sealing, that is, bonding the elastic polymeric layer 12 to the second coating layer 15 on the other hand.

The first coating layer 13 and the metal layer 14 are in a first morphology, and the elastic polymeric layer 12 and the second coating layer 15 are in a second morphology, which is different from the first morphology. The first form may be defined as a structure having the same shape and not having the same size, a structure having the same shape and having the same size, a structure having the same size within a certain range, or a structure having the same size and not having the same shape, wherein the first form may be defined as the first coating layer 13 and the metal layer 14 having the same shape and not having the same size. The second form may be positioned such that the elastic polymeric layer 12 and the second coating layer 15 have the same shape, are not the same size, have the same shape, have a certain range of sizes, and have no same shape.

The first form and the second form may be different from each other in terms of a certain structural parameter, all parameters, or the same parameter and the structure, that is, the first form and the second form may be considered to be different from each other in terms of the shape or the structural parameter.

Specifically, the first coating layer 13 and the metal layer 14 may be in a first size range and have the same first shape, the second coating layer 15 and the elastic polymer layer 12 are in a second size range and have the same first shape, that is, the length range of the first size is different from the length range of the second size, and the size includes a thickness, for example, the first coating layer 13 and the metal layer 14 have a length of 10-200 mm and a width of 1-200 mm, the first coating layer 13 and the metal layer 14 have a thickness of 10 nm-100 mm, and the first coating layer 13 and the metal layer 14 have a rectangular shape, the second coating layer 15 and the elastic polymer layer 12 have a length of 10-200 mm and a width of 1-200 mm, and the second coating layer 15 and the elastic polymer layer 12 have a rectangular shape.

The first coating layer 13 and the metal layer 14 may also have a first size and have the same first shape, the second pattern layer and the elastic polymer layer 12 have a second size and have the same first shape, for example, the first coating layer 13 and the metal layer 14 have a length of 60 mm, a width of 5 mm, a first coating thickness of 3 μm, a metal layer thickness of 100 nm, the first coating layer 13 and the metal layer 14 are square, the second coating layer 15 and the elastic polymer layer 12 have a length of 65 mm, a width of 6 mm, and a thickness of 3 μm, and the second coating layer 15 and the elastic polymer layer 12 are square.

The first coating layer 13 and the metal layer 14 may be in a first size range and have the same first shape, the second coating layer and the elastic polymer layer 12 are in a first size range and have the same second shape, that is, the first shape and the second shape are different, for example, the first coating layer 13 and the metal layer 14 have a size of 10-100 mm in length and 1-20 mm in width, the first coating layer has a thickness of 1-10 μm and the metal layer has a thickness of 50-500 nm while the first coating layer 13 and the metal layer 14 are both elliptical, the second coating layer 15 and the elastic polymer layer 12 have a size of 10-100 mm and a width of 1-20 mm and a thickness of 1-10 μm while the second coating layer 15 and the elastic polymer layer 12 are both rectangular. The first and second configurations optimize the efficiency of contact of the electrode with the cerebral cortex and the ability to reduce brain tissue damage by their different shapes.

Specifically, the electrode 10 of the implantable brain-computer interface of the present embodiment may be an ECoG electrode (conventionally called a semi-implantable neural electrode), a probe electrode (conventionally called a fully implantable neural electrode), or some other implantable electrode. The organism in this embodiment may be a human, pig, monkey, mouse or other organism. The elastic polymeric layer 12 in this embodiment may be silica gel, polydimethylsiloxane (PDMS), polyurethane (PU), silicone rubber, or the like. The elastic polymer layer is formed by spin coating, spray coating, injection molding, mould pressing and the like, and is cured by heating. For example, if the living organism is a human, the elastic polymeric layer 12 is made of silica gel, the surface of the silica gel is attached to the cerebral cortex of the human, the brain electrical signal of the patient is obtained through the metal layer 14, and then the brain electrical signal is transmitted to the external analysis equipment, and the brain electrical signal is analyzed through the external analysis equipment. The first coating 13 and the second coating 15 in this embodiment may be Polyimide (PI), parylene (Parylene), polyurethane (PU), or the like. The first coating 13 and the second coating 15 are manufactured by Physical Vapor Deposition (PVD).

Further, the first coating layer 13 and the metal layer 14 are combined with each other to form an intermediate layer, and the elastic polymer layer 12 and the second coating layer 15 are combined with each other to form a wrapping layer, wherein the intermediate layer is disposed in the wrapping layer. That is, the elastic polymeric layer 12 and the second coating 15 seal and encapsulate the first coating 13 and the metal layer 14, so as to prevent the metal layer 14 and the first coating 13 from being immersed by cerebrospinal fluid, and influence the detection and transmission functions of the metal layer 14.

The whole area of the wrapping layer is not smaller than the whole surface area of the middle layer because the wrapping layer wraps the middle layer, that is, the surface area of the elastic polymer layer 12 and the second coating layer 15 is larger than the surface area of the first coating layer 13 and the metal layer 14, and meanwhile, the edge of the first coating layer 13 is attached to the edge of the metal layer 14, and the edge of the elastic polymer layer 12 is attached to the edge of the second coating layer 15.

Further, a conductive polymer layer 16 is disposed above the second coating layer 15, a through hole is disposed on the first surface of the second coating layer 15, and the conductive polymer layer 16 passes through the first surface of the second coating layer 15 and is attached to the metal layer 14. The conductive polymer layer 16 may be a conductive polymer or metal, in which the purpose of reducing the electrode impedance is achieved, the metal to be plated may be gold or Pt, the conductive polymer to be plated may be one or more of polyaniline, polythiophene, polypyrrole, etc., preferably, the conductive polymer to be plated is polyethylene dioxythiophene, and the plating parameters are finely adjusted according to the electrode site size.

A third coating 11 is further arranged below the elastic polymeric layer 12 and is attached to the elastic polymeric layer 12, wherein the third coating 11 can be Polyimide (PI), parylene (Parylene), polyurethane (PU) and the like. The metal layer is made by vacuum evaporation or magnetron sputtering, the metal layer material is one or more of gold, silver, copper, platinum and the like, and preferably, the metal layer material is one or more of gold and platinum. The provision of the third coating 11 allows the electrode 10 to have a better sealing and moisture-proof effect, and at the same time, the third coating 11 reduces friction between the electrode 10 and the dura mater and reduces immune response when the electrode 10 is placed under the dura mater.

Further, as shown in FIG. 3, the metal layer 14 at least includes an adhesion metal layer 143, a conductive layer 142, and a metal protection layer 141, and the adhesion metal layer 143, the conductive layer 142, and the metal protection layer 141 are stacked in order. The adhesion metal layer 143 is used for adhesion between the second coating 15 and the conductive layer 142, the conductive layer 142 is used for acquiring and transmitting brain electrical signals, and the metal protection layer 141 is used for protecting and buffering the metal layer 14.

Further, as shown in fig. 4, the electrode 10 includes at least a detecting portion 101 for mainly acquiring brain electrical signals, a transmitting portion 102 for transmitting the brain electrical signals to the outside of the brain, and an interface portion 103 for connecting with external devices. That is, each of the third coating layer 11, the elastic polymeric layer 12, the first coating layer 13, the metal layer 14, the second coating layer 15, and the conductive polymeric layer 16 includes a detection portion 101, a transmission portion 102, and an interface portion 103. The detecting portion 101, the transmitting portion 102 and the interface portion 103 may be integrally formed or may be detachably mounted. And the integrated forming is more efficient in production and use. The detection part 101 is connected with the transmission part 102, the transmission part 102 is connected with the interface part 103 to form a transmission path of the electrode 10, the detection part 101 can be rectangular, the transmission part 102 can be rectangular, the interface part 103 can be rectangular, the detection part 101 can also be square or round, the transmission part 102 can be rectangular, and the interface part 103 can be rectangular or round.

An embodiment of the present utility model proposes an apparatus for an implantable brain-computer interface, in which the electrode 10 is connected to an external device, which itself may include a signal conversion means and a data analysis means, or the external device may be a separate device, which is a signal conversion device and a data analysis device, respectively, but functions are signal conversion and electrical signal analysis processing, respectively.

Specifically, the signal conversion may be conversion between a digital signal and an analog signal, or may be conversion of other types of signals. The data analysis device may be configured to parse the electrical brain signals to obtain brain data.

The foregoing is merely illustrative of the present utility model, and the present utility model is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present utility model. Therefore, the protection scope of the present utility model shall be subject to the protection scope of the claims.

Claims (10)

1. An electrode for an implantable brain-computer interface, wherein a portion of the electrode is in contact with a cerebral cortex of a living being for acquiring brain electrical signals;

The electrode at least comprises an elastic polymeric layer, a first coating, a metal layer and a second coating;

wherein the first coating layer and the metal layer belong to a first morphology, and the elastic polymeric layer and the second coating layer belong to a second morphology;

wherein the first morphology is different from the second morphology.

2. The electrode of claim 1, wherein the elastic polymeric layer, the first coating layer, the metal layer, and the second coating layer are stacked in this order;

after the first coating and the metal layer are combined with each other, an intermediate layer is formed;

the elastic polymeric layer and the second coating are combined with each other to form a wrapping layer;

The middle layer is arranged in the wrapping layer.

3. The electrode of claim 2, further comprising a conductive polymeric layer, a third coating;

The conductive polymeric layer is disposed over the second coating;

The third coating is arranged below the elastic polymerization layer and is attached to the elastic polymerization layer.

4. An electrode according to claim 3, wherein the first surface of the second coating is provided with a through hole through which the conductive polymeric layer is bonded to the metal layer.

5. The electrode according to claim 1, wherein the metal layer comprises at least an adhesion metal layer, a conductive layer, and a metal protective layer;

The adhesion metal layer, the conductive layer and the metal protection layer are sequentially stacked;

The adhesion metal layer is attached to the first coating, and the metal protection layer is attached to the second coating.

6. An electrode according to claim 2, wherein,

The edge of the first coating is attached to the edge of the metal layer;

the edge of the elastic polymeric layer is attached to the edge of the second coating layer;

Wherein the surface area of the elastic polymeric layer and the second coating layer is greater than the surface area of the first coating layer and the metal layer.

7. The electrode according to claim 1, wherein the electrode comprises a detecting section, a transmitting section, and an interface section;

the detection part, the transmission part and the interface part are integrally formed.

8. The electrode according to claim 7, wherein the detecting portion has a rectangular shape, the transmitting portion has a linear shape, and the interface portion has a rectangular shape;

Wherein the detection part is connected with the transmission part;

The transmission part is connected with the interface part.

9. The electrode according to claim 1, wherein,

The first form is a first shape;

The second form is a second shape;

wherein the first shape is different from the second shape.

10. An apparatus for an implantable brain-computer interface, comprising an electrode according to any one of claims 1-9, said electrode being connected to an external device;

the external device includes a signal conversion section and a data analysis section;

The signal conversion component is used for converting data between a digital signal and an analog signal;

The data analysis component is used for analyzing and processing the brain electrical signals so as to acquire brain data.