A method and device for vestibular electrical stimulation based on virtual reality cognitive rehabilitation

Abstract

This invention provides a vestibular electrical stimulation method and device based on virtual reality cognitive rehabilitation, including a virtual reality screen, a vestibular electrical stimulation device, and a plantar pressure plate. The vestibular electrical stimulation device includes a control motherboard, a headband-type inertial sensor, and electrode pads. The headband-type inertial sensor acquires the vertical swing angle of the head. The electrode pads are attached to the mastoid processes behind the ears on both sides of the body to output stimulation current. The plantar pressure plate is placed on the soles of the feet to collect pressure data of the feet during virtual reality rehabilitation training. The control motherboard calculates the stimulation sequence and stimulation current intensity, and drives the electrode pads to output corresponding stimuli. This invention rationally designs different stimulation sequences and intensities to meet the real-time stimulation effect for patients during virtual reality rehabilitation training.

Description

Technical Field

[0001] This invention relates to the field of motor cognitive rehabilitation technology, and in particular to a vestibular electrical stimulation method and device based on virtual reality cognitive rehabilitation. Background Technology

[0002] Currently, Virtual Reality (VR) technology can create virtual environments and use visual stimulation to achieve cognitive assessment and rehabilitation, making it possible for VR to improve age-related cognitive decline and cognitive impairment. Non-invasive brain stimulation (NIBS) is increasingly being used to explore the functional mechanisms of the brain and induce therapeutic regulation of behavior, cognition, and emotion. Vestibular stimulation (GVS) is a safe and well-tolerated NIBS technique that can modulate the activity of various cortical and subcortical areas involved in vestibular and multisensory processing. It is a technique that alters vestibular system feedback by creating an artificial potential difference by applying a small current (≤3.5mA) at the mastoid process behind the ear. The vestibular system, located in the inner ear, plays a key role in changes in head posture and movement, involving balance, spatial orientation, and gaze stability. Stimulation can induce tilting and swaying motion perception in the body. Existing virtual reality rehabilitation training currently focuses on improving patients' motor cognition through visual stimulation. Summary of the Invention

[0003] To address the problems existing in the prior art, this invention proposes a vestibular electrical stimulation system and implementation device based on virtual reality cognitive rehabilitation. This method helps to achieve training balance for patients with cognitive impairment in a virtual reality rehabilitation environment, and produces stimulation effects and cognitive improvement through vestibular stimulation.

[0004] Specifically, this invention proposes a vestibular electrical stimulation method for virtual reality-based cognitive rehabilitation. The implementation of this method includes the following steps:

[0005] Step S1: Select the corresponding virtual reality rehabilitation scene and generate a virtual reality scene image;

[0006] Step S2: Based on frame-by-frame deflection analysis of virtual reality scene images, generate real-time deflection angle θ;

[0007] Step S3: Real-time human motion data acquisition and analysis, including the real-time human body deflection angle θ' and the weighting coefficient K of the center of gravity shift caused by head swaying;

[0008] Step S4: Generate the corresponding stimulus timing and stimulus intensity composition based on the difference between the real-time image deflection angle θ and the real-time human body deflection angle θ'.

[0009] Step S4 further includes the following steps:

[0010] Step S41: Calculate the difference between the real-time image deflection angle θ and the real-time human body deflection angle θ' to determine the stimulus timing.

[0011] Step S42: Generate stimulation current intensity based on the real-time deflection angle θ of the image and the real-time deflection angle θ' of the human body;

[0012] Step S43: Stimulate the vestibular system according to the stimulation sequence and stimulation current intensity.

[0013] Furthermore, step 2 also includes the following steps:

[0014] Step S21 involves converting the virtual reality scene image into a grayscale image;

[0015] Step S22: Calibrate the position of the first frame image and establish the XOY coordinate system;

[0016] In the first frame, with the center point of the image as the origin O, select at least 50 pixels horizontally as the X-axis to generate the X-axis matrix [X1, X2...X]. 50 Establish a vertical Y-axis by selecting at least 50 pixels, and generate a Y-axis matrix [Y1, Y2...Y]. 50 ];

[0017] Step S23: Establish a new coordinate system POQ in the second frame image, identify the position in the XOY image, and calculate the real-time image deflection angle θ;

[0018] Step S24: Set the second frame image as the first frame image, and repeat the above operation.

[0019] Furthermore, step 3 also includes the following steps:

[0020] Step S31: Output the real-time human body deflection angle θ' based on the balance analysis of plantar pressure offset;

[0021] Step S32: Obtain the real-time head tilt angle and calculate the weighting coefficient K of the center of gravity offset by combining the real-time human body tilt angle θ'.

[0022] Furthermore, in step 31, the formula for calculating the real-time human body deflection angle θ' is:

[0023]

[0024] L represents the percentage of body weight borne by the left foot, R represents the percentage of body weight borne by the right foot, and MAX(L,R) indicates selecting the larger of L or R.

[0025] Furthermore, in step 32, the weighting coefficient K for the center of gravity shift caused by head movement is:

[0026]

[0027] K is the weighting coefficient for the center of gravity shift, and N is the real-time head deflection angle.

[0028] Furthermore, in step 41, the stimulation sequence includes no stimulation; the left ear electrode is positive and the right ear electrode is negative; the left ear electrode is negative and the right ear electrode is positive.

[0029] When the body is tilted to the left, the formula for calculating the stimulation sequence is:

[0030]

[0031] When the body is tilted to the right, the formula for calculating the stimulation sequence is:

[0032]

[0033] θ' is the real-time human body deflection angle, and θ is the real-time image deflection angle.

[0034] Furthermore, in step 42, the formula for calculating the real-time stimulus intensity is:

[0035]

[0036] Where I is the current intensity of the real-time stimulus, and θ0-θ'0 is the difference between the initially calculated real-time image deflection angle and the initially calculated real-time human body deflection angle.

[0037] Furthermore, in step 23, in the second frame image, with the midpoint of the image as the origin, the horizontal direction is selected as the P-axis, and the vertical direction as the Q-axis, to establish the POQ coordinate matrix:

[0038]

[0039] Based on image recognition, the X-axis matrix [X1, X2...X] in the first frame is... 50 ], Y-axis matrix [Y1, Y2...Y 50 Establish the XOY coordinate matrix in the second frame image:

[0040]

[0041] The formula for calculating the real-time image deflection angle θ is:

[0042]

[0043] θ is the real-time image deflection angle.

[0044] A vestibular electrical stimulation device based on virtual reality cognitive rehabilitation is also provided, the vestibular electrical stimulation device including a virtual reality screen, a vestibular electrical stimulation device and a plantar pressure plate;

[0045] The vestibular electrical stimulation device includes a control board, a headband-type inertial sensor, and electrode pads;

[0046] The headband-type inertial sensor acquires the vertical swing angle of the head;

[0047] The electrode pads are attached to the mastoid process behind both ears of the human body to output stimulation current.

[0048] The foot pressure plate is placed on the sole of the human foot to collect pressure data of the human feet during virtual reality rehabilitation training.

[0049] The control motherboard is used to collect and analyze images in the virtual reality screen and obtain the real-time image deflection angle; the control motherboard acquires the pressure data of the human body's two feet and calculates the weighting coefficients of the real-time human body deflection angle and center of gravity shift; the control motherboard calculates the stimulation timing and stimulation current intensity, and drives the electrode pads to output corresponding stimuli.

[0050] The beneficial effects achieved by this invention are:

[0051] This invention combines virtual reality rehabilitation training with vestibular electrical stimulation technology to provide a motor cognition enhancement program with training memory; and designs different stimulation sequences and intensities to meet the effect of real-time stimulation for patients in virtual reality rehabilitation training.

[0052] This invention provides a vestibular electrical stimulation method based on virtual reality cognitive rehabilitation, which combines virtual reality rehabilitation with vestibular electrical stimulation technology to achieve a real-time feedback and continuous intervention.

[0053] This invention provides a vestibular electrical stimulation method based on virtual reality cognitive rehabilitation. It uses scene and motion capture and recognition to calculate intervention parameters in real time, achieving personalized intervention effects for people with different degrees of illness. At the same time, it combines the deflection after real-time intervention with the initial deflection to realize automatic adjustment of the intervention stimulus, thereby making the stimulation effect more precise. Attached Figure Description

[0054] like Figure 1 This invention provides a schematic flowchart of a vestibular electrical stimulation method for cognitive rehabilitation based on virtual reality.

[0055] like Figure 2 This invention provides a schematic diagram of the structure of a vestibular electrical stimulation device based on virtual reality cognitive rehabilitation.

[0056] like Figure 3 This invention provides a schematic diagram of the process for generating a real-time deflection angle θ of an image based on frame-by-frame deflection analysis of virtual reality scene images in a vestibular electrical stimulation method for cognitive rehabilitation based on virtual reality.

[0057] like Figure 4 This invention provides a schematic diagram of the process of establishing a new coordinate system POQ in the second frame image, identifying the position in the XOY image, and calculating the real-time deflection angle θ of the image in a vestibular electrical stimulation method based on virtual reality cognitive rehabilitation.

[0058] like Figure 5 This invention provides a schematic diagram of the process for generating corresponding stimulation timing and intensity based on the difference between the real-time deflection angle θ of the image and the real-time deflection angle θ' of the human body in a vestibular electrical stimulation method for virtual reality cognitive rehabilitation.

[0059] like Figure 6 This invention provides a schematic flowchart for determining the stimulation sequence in a vestibular electrical stimulation method based on virtual reality cognitive rehabilitation. Detailed Implementation

[0060] The technical solution of the present invention will be described in more detail below with reference to the accompanying drawings. The present invention includes, but is not limited to, the following embodiments.

[0061] Example 1

[0062] As attached Figure 1 As shown, this invention provides a vestibular electrical stimulation method for cognitive rehabilitation based on virtual reality, which includes the following steps:

[0063] Step S1: Select the corresponding virtual reality rehabilitation scene and enter the virtual reality rehabilitation experience;

[0064] Virtual reality rehabilitation scenarios include movement tasks involving body balance, such as walking straight, stepping, balancing, squatting, and turning.

[0065] Step S2: Based on frame-by-frame deflection analysis of virtual reality scene images, generate real-time deflection angle θ;

[0066] Step S2 further includes the following steps:

[0067] Step S21 involves converting the image into a grayscale image;

[0068] The image is converted into a grayscale image, where the color space coordinates of each pixel in the image are represented by 0 to 255;

[0069] Step S22: Calibrate the position of the first frame image and establish the XOY coordinate system;

[0070] In the first frame, with the center point of the image as the origin O, select at least 50 pixels horizontally as the X-axis to generate the X-axis matrix [X1, X2...X]. 50Establish a vertical Y-axis by selecting at least 50 pixels, and generate a Y-axis matrix [Y1, Y2...Y]. 50 ];

[0071] Step S23: Establish a new coordinate system POQ in the second frame image, identify the position in the XOY image, and calculate the real-time image deflection angle θ;

[0072] In the second frame image, with the midpoint of the image as the origin, the horizontal direction is selected as the P-axis, and the vertical direction as the Q-axis, to establish the POQ coordinate matrix:

[0073]

[0074] Based on image recognition, the X-axis matrix [X1, X2...X] in the first frame is... 50 ], Y-axis matrix [Y1, Y2...Y 50 Establish the XOY coordinate matrix in the second frame image:

[0075]

[0076] The formula for calculating the real-time image deflection angle θ is:

[0077]

[0078] Step S24: Set the second frame image as the first frame image, and repeat the above operation.

[0079] Set the POQ coordinate system to the XOY coordinate system and loop continuously until the video ends;

[0080] Step S3: Real-time human motion data acquisition and analysis, including the real-time human body deflection angle θ' and the weighting coefficient K of the center of gravity shift caused by head swaying;

[0081] Step S3 further includes the following steps:

[0082] Step S31: Output the human body center of gravity offset based on the balance analysis of plantar pressure offset;

[0083] The system collects real-time data on the pressure distributed between the patient's feet during virtual reality rehabilitation training, calculates the proportion of body weight borne by the left foot (L) and the proportion by the right foot (R), and then determines the body's center of gravity shift. The specific formula is as follows:

[0084]

[0085] The formula for calculating the real-time human body deflection angle θ' is:

[0086]

[0087] MAX(L,R) means selecting the larger of L and R;

[0088] Step S32: Analyze head motion based on IMU data and output the amount of head deflection.

[0089] Collect the patient's real-time head tilt angle during virtual reality rehabilitation training and record the vertical head tilt angle N;

[0090] The weighting coefficient K for calculating the shift in the center of gravity caused by head movement is:

[0091]

[0092] K is the weighting coefficient for the centroid offset;

[0093] When the measured vertical head swing angle N is 15° and the real-time body deflection angle θ' is 20°, then K = 15° / 20° = 0.75.

[0094] Step S4: Generate the corresponding stimulus timing and stimulus intensity composition based on the difference between the real-time image deflection angle θ and the real-time human body deflection angle θ'.

[0095] Step S4 further includes the following steps:

[0096] Step S41, determine the stimulus timing;

[0097] Calculate the difference between the real-time image deflection angle θ and the real-time human body deflection angle θ', and calculate the stimulus timing based on the difference;

[0098] The system is set with three stimulation sequences: no stimulation; positive electrode behind the left ear and negative electrode behind the right ear; negative electrode behind the left ear and positive electrode behind the right ear.

[0099] When the body is tilted to the left, the formula for calculating the stimulation sequence is:

[0100]

[0101] When the body is tilted to the right, the formula for calculating the stimulation sequence is:

[0102]

[0103] Step S42, generate stimulation current intensity;

[0104] Using the initially calculated θ-θ' value as a 3.5mA stimulation current, the formula for calculating the real-time stimulation intensity is:

[0105]

[0106] Where I is the current intensity of the real-time stimulus, and θ0-θ0 is the initial calculated θ-θ';

[0107] Step S43: Stimulate the vestibular system according to the above stimulation sequence and intensity;

[0108] This completes one cycle of the system. The next real-time cycle begins with step S2, repeating the above process to improve the patient's motor cognition and gradually bring their movements closer to the training expectations.

[0109] The method is further illustrated by a specific embodiment. In the first loop, the real-time deflection angle θ of the image is 30°, the real-time deflection angle θ' of the human body is 20°, and the difference is 10.

[0110] The timing of the first stimulation is selected as follows: left positive, right negative, that is, the electrode at the mastoid process behind the left ear is set as the positive electrode, and the electrode at the mastoid process behind the right ear is set as the negative electrode.

[0111] The current calculation for implementation is as follows:

[0112]

[0113] The system enters the second loop. For example, if the real-time image deflection angle θ is 32° and the real-time human body deflection angle θ' is 25°, the difference is 7.

[0114] The timing of the second stimulation is selected as follows: left positive, right negative, that is, the electrode at the mastoid process behind the left ear is set as positive, and the electrode at the mastoid process behind the right ear is set as negative.

[0115] The current calculation for implementation is as follows:

[0116]

[0117] Example 2

[0118] This invention provides a vestibular electrical stimulation device for cognitive rehabilitation based on virtual reality. The device includes a virtual reality screen 1, a vestibular electrical stimulation device 2, and a plantar pressure plate 3.

[0119] The virtual reality rehabilitation scene is displayed on virtual reality screen 1;

[0120] The vestibular electrical stimulation device 2 includes an attachment bracket 21, a control main board 22, a headband-type inertial sensor 23, and electrode pads 24.

[0121] The attachment bracket 21 has holes for connecting to the control motherboard 22 and can be attached to the human neck.

[0122] The control motherboard 22 can collect and analyze images in the virtual reality screen 1, acquire data from the headband inertial sensor 23 and the foot pressure plate 3, and output the corresponding stimulation parameters to the electrode pads 24.

[0123] The control motherboard 22 converts the image into a grayscale image, where the color space coordinates of each pixel in the image are represented by 0 to 255.

[0124] Define the position of the first frame image and establish the XOY coordinate system;

[0125] In the first frame, with the center of the image as the origin, select at least 50 pixels horizontally as the X-axis to generate an X-axis matrix [X1, X2...X]. 50 Establish a vertical Y-axis by selecting at least 50 pixels, and generate a Y-axis matrix [Y1, Y2...Y]. 50 ];

[0126] Establish a new coordinate system POQ in the second frame image, identify the position in the XOY image, and calculate the deflection angle θ;

[0127] In the second frame image, with the midpoint of the image as the origin, the horizontal direction is selected as the P-axis, and the vertical direction as the Q-axis, to establish the POQ coordinate matrix:

[0128]

[0129] Based on image recognition, the X-axis matrix [X1, X2...X] in the first frame is... 50 ], Y-axis matrix [Y1, Y2...Y 50 Establish the XOY coordinate matrix in the second frame image:

[0130]

[0131] The formula for calculating the deflection angle θ is:

[0132]

[0133] The control motherboard 22 sets the second frame image as the first frame image and sets the POQ coordinate system to the XOY coordinate system, continuously looping until the video ends.

[0134] The headband-type inertial sensor 23 collects the real-time head rotation angle of the patient during virtual reality rehabilitation training and records the vertical head swing angle N.

[0135] The weighting coefficient K for calculating the shift in the center of gravity caused by head movement is:

[0136]

[0137] The headband-type inertial sensor 23 is worn on the human head to detect the motion data of the human head;

[0138] The foot pressure plate 3 is placed on the sole of the human foot to collect pressure data of the human feet during virtual reality rehabilitation training.

[0139] The foot pressure plate 3 collects real-time data on the pressure distributed between the patient's feet during virtual reality rehabilitation training, calculating the percentage of body weight borne by the left foot (L%) and the percentage of body weight borne by the right foot (R%). This allows for the determination of the body's center of gravity shift. The specific determination formula is as follows:

[0140]

[0141] The formula for calculating the real-time human body deflection angle θ' is:

[0142]

[0143] Electrode pads 24 are attached to the mastoid process behind the ears on both sides of the human body to output stimulation current;

[0144] The electrode pad 24 is set with three stimulation sequences: no stimulation; the left ear electrode is positive and the right ear electrode is negative; the left ear electrode is negative and the right ear electrode is positive.

[0145] When the body is tilted to the left, the formula for calculating the stimulation sequence is:

[0146]

[0147] When the body is tilted to the right, the formula for calculating the stimulation sequence is:

[0148]

[0149] Using the initially calculated θ-θ' value as a 3.5mA stimulation current, the formula for calculating the real-time stimulation intensity is:

[0150]

[0151] Where I is the current intensity of the real-time stimulus, and θ0-θ'0 is the initial calculated θ-θ';

[0152] Finally, the vestibular system is stimulated by electrode pads 24 according to the above-mentioned stimulation sequence and intensity.

[0153] The vestibular electrical stimulation method system based on virtual reality cognitive rehabilitation proposed in this invention aims to induce leftward deviation in patients. This requires enhancing the firing rate of proprioceptors on the left side to activate ipsilateral muscle contraction, resulting in deflection; that is, left negative, right positive, thus inducing leftward deviation. Similarly, when the system aims to induce rightward deviation, it requires enhancing the firing rate of proprioceptors on the right side to activate ipsilateral muscle contraction, resulting in deflection; that is, left positive, right negative, thus inducing rightward deviation.

[0154] The system uses the initial deviation value θ-θ' as the calibration for the maximum stimulation current of 3.5mA. As stimulation is applied, the value of θ-θ' will gradually decrease. One of the innovations of this system is to establish a correspondence between the current applied for stimulation and the real-time value of θ-θ', thereby clarifying the magnitude of the stimulation current.

[0155] This invention is not limited to the specific embodiments described above. Those skilled in the art can implement this invention using various other specific embodiments based on the disclosed content of the embodiments and accompanying drawings. Therefore, any design that adopts the design structure and concept of this invention and makes some simple changes or modifications falls within the protection scope of this invention.

Claims

1. A vestibular electrical stimulation method for cognitive rehabilitation based on virtual reality, characterized in that, Implementing a vestibular electrical stimulation method based on virtual reality cognitive rehabilitation includes the following steps: Step S1: Select the corresponding virtual reality rehabilitation scene and generate a virtual reality scene image; Step S2: Based on frame-by-frame deflection analysis of virtual reality scene images, generate real-time deflection angle θ; Step S3: Real-time human motion data acquisition and analysis, including the real-time human body deflection angle θ' and the weighting coefficient K of the center of gravity shift caused by head swaying; Step S4: Generate the corresponding stimulus timing and stimulus intensity composition based on the difference between the real-time image deflection angle θ and the real-time human body deflection angle θ'. Step S4 further includes the following steps: Step S41: Calculate the difference between the real-time image deflection angle θ and the real-time human body deflection angle θ' to determine the stimulus timing. Step S42: Generate stimulation current intensity based on the real-time deflection angle θ of the image and the real-time deflection angle θ' of the human body; Step S43: Stimulate the vestibular system according to the stimulation sequence and stimulation current intensity; Step 3 also includes the following steps: Step S31: Output the real-time human body deflection angle θ' based on the balance analysis of plantar pressure offset; Step S32: Obtain the real-time head tilt angle and calculate the weighting coefficient K of the center of gravity offset by combining the real-time human body tilt angle θ'. In step 31, the formula for calculating the real-time human body deflection angle θ' is: L represents the percentage of body weight borne by the left foot, R represents the percentage of body weight borne by the right foot, and MAX(L,R) indicates selecting the larger of L or R. In step 32, the weighting coefficient K for the center of gravity shift caused by head movement is: K is the weighting coefficient for the center of gravity shift, and N is the real-time head deflection angle; In step 41, the stimulation sequence includes no stimulation; the left ear electrode is positive and the right ear electrode is negative; the left ear electrode is negative and the right ear electrode is positive. When the body is tilted to the left, the formula for calculating the stimulation sequence is: When the body is tilted to the right, the formula for calculating the stimulation sequence is: θ' is the real-time human body deflection angle, and θ is the real-time image deflection angle; In step 42, the formula for calculating the real-time stimulus intensity is: Where I is the current intensity of the real-time stimulus, and θ0-θ'0 is the difference between the initially calculated real-time image deflection angle and the initially calculated real-time human body deflection angle.

2. The vestibular electrical stimulation method for virtual reality-based cognitive rehabilitation according to claim 1, characterized in that, Step 2 also includes the following steps: Step S21 involves converting the virtual reality scene image into a grayscale image; Step S22: Calibrate the position of the first frame image and establish the XOY coordinate system; In the first frame, with the center point of the image as the origin O, select at least 50 pixels horizontally as the X-axis to generate the X-axis matrix [X1, X2...X]. 50 Establish a vertical Y-axis by selecting at least 50 pixels, and generate a Y-axis matrix [Y1, Y2...Y]. 50 ]; Step S23: Establish a new coordinate system POQ in the second frame image, identify the position in the XOY image, and calculate the real-time image deflection angle θ; Step S24: Set the second frame image as the first frame image, and repeat the above operation.

3. The vestibular electrical stimulation method for virtual reality-based cognitive rehabilitation according to claim 2, characterized in that, In step 23, in the second frame image, with the midpoint of the image as the origin, the horizontal direction is selected as the P-axis, and the vertical direction is selected as the Q-axis to establish the POQ coordinate matrix: Based on image recognition, the X-axis matrix [X1, X2...X] in the first frame is... 50 ], Y-axis matrix [Y1, Y2...Y 50 Establish the XOY coordinate matrix in the second frame image: The formula for calculating the real-time image deflection angle θ is: θ is the real-time image deflection angle.

4. A vestibular electrical stimulation device based on the vestibular electrical stimulation method for virtual reality cognitive rehabilitation according to any one of claims 1-3, characterized in that, The vestibular electrical stimulation device includes a virtual reality screen (1), a vestibular electrical stimulation device (2), and a plantar pressure plate (3); The vestibular electrical stimulation device (2) includes a control motherboard (22), a headband-type inertial sensor (23), and electrode pads (24); The headband-type inertial sensor (23) acquires the vertical swing angle of the head; The electrode pads (24) are attached to the mastoid process behind the ears on both sides of the human body to output stimulation current; The foot pressure plate (3) is placed on the sole of the human foot to collect pressure data of the human feet during virtual reality rehabilitation training; The control motherboard (22) is used to collect and analyze images in the virtual reality screen (1) and obtain the real-time deflection angle of the image; the control motherboard (22) acquires the pressure data of the human body's two feet, calculates the weight coefficients of the real-time human body deflection angle and center of gravity shift; the control motherboard (22) calculates the stimulation timing and stimulation current intensity, and drives the electrode sheet (24) to output the corresponding stimulation.

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