METHOD FOR CALIBRATING ON-LINE AND WITH FORGETTING FACTOR A DIRECT NEURAL INTERFACE WITH PENALISED MULTIVARIATE REGRESSION

    公开(公告)号:US20220110570A1

    公开(公告)日:2022-04-14

    申请号:US17450601

    申请日:2021-10-12

    IPC分类号: A61B5/279 G06K9/64 G06F3/01

    摘要: The present invention relates to a method for calibrating on-line a direct neural interface implementing a REW-NPLS regression between an output calibration tensor and an input calibration tensor. The REW-NPLS regression comprises a PARAFAC iterative decomposition of the cross covariance tensor between the input calibration tensor and the output calibration tensor, each PARAFAC iteration comprising a sequence of M elementary steps (2401, 2401, . . . 240M) of minimisation of a metric according to the alternating least squares method, each elementary minimisation step relating to a projector and considering the others as constant, said metric comprising a penalisation term that is a function of the norm of this projector, the elements of this projector not being subjected to a penalisation during a PARAFAC iteration f not being penalisable during following PARAFAC iterations. Said calibration method makes it possible to obtain a predictive model of which the non-zero coefficients are sparse blockwise.

    DIRECT NEURAL INTERFACE SYSTEM AND METHOD
    3.
    发明申请
    DIRECT NEURAL INTERFACE SYSTEM AND METHOD 审中-公开
    直接神经接口系统和方法

    公开(公告)号:US20160282941A1

    公开(公告)日:2016-09-29

    申请号:US15032546

    申请日:2013-10-31

    IPC分类号: G06F3/01 A61B5/0476 A61B5/04

    摘要: A direct neural interface system comprises: a signal acquisition subsystem for acquiring electrophysiological signals representative of neuronal activity of a subject's brain; and a processing unit for representing electrophysiological signals acquired over an observation time window in the form of a N-way data tensor, N being greater than or equal to two, and generating command signals for a machine by applying a regression model over the data tensor; wherein the processing unit is configured or programmed for generating command signals for a machine by applying Generalized Linear regression, with a nonlinear link function, over the data tensor. A method of interfacing a subject's brain to a machine by using such a direct neural interface system is provided.

    摘要翻译: 直接神经接口系统包括:信号采集子系统,用于获取表示受试者脑部神经元活动的电生理信号; 以及处理单元,用于表示通过N次数据张量N的大小等于2的观测时间窗口获取的电生理信号,并且通过在数据张量上应用回归模型来生成机器的命令信号 ; 其中所述处理单元被配置或编程以通过在数据张量上应用具有非线性链接功能的广义线性回归来为机器产生命令信号。 提供了通过使用这样的直接神经接口系统将受试者的大脑与机器接口的方法。

    ADAPTIVE TRAINING METHOD OF A BRAIN COMPUTER INTERFACE USING A PHYSICAL MENTAL STATE DETECTION

    公开(公告)号:US20220207424A1

    公开(公告)日:2022-06-30

    申请号:US17563700

    申请日:2021-12-28

    IPC分类号: G06N20/00 G06N5/04

    摘要: The present invention relates to an adaptive training method of a brain computer interface. The ECoG signals expressing the neural command of the subject are preprocessed to provide at each observation instant an observation data tensor to a predictive model that deduces therefrom a command data tensor making it possible to control a set of effectors. A satisfaction/error mental state decoder predicts at each epoch a satisfaction or error state from the observation data tensor. The mental state predicted at a given instant is used by an automatic data labelling module to generate on the fly new training data from the pair formed by the observation data tensor and the command data tensor at the preceding instant. The parameters of the predictive model are subsequently updated by minimising a cost function on the training data thus generated.

    ITERATIVE CALIBRATION METHOD FOR A DIRECT NEURAL INTERFACE USING A MARKOV MIXTURE OF EXPERTS WITH MULTIVARIATE REGRESSION

    公开(公告)号:US20210064942A1

    公开(公告)日:2021-03-04

    申请号:US17011276

    申请日:2020-09-03

    IPC分类号: G06K9/62 A61B5/04 G06N20/00

    摘要: This invention relates to a method of calibrating a direct neural interface with continuous coding. The observation variable is modelled by an HMM model and the control variable is estimated by means of a Markov mixture of experts, each expert being associated with a state of the model.
    During each calibration phase, the predictive model of each of the experts is trained on a sub-sequence of observation instants corresponding to the state with which it is associated, using an REW-NPLS (Recursive Exponentially Weighted N-way Partial Least Squares) regression model.
    A second predictive model giving the probability of occupancy of each state of the HMM model is also trained during each calibration phase using an REW-NPLS regression method. This second predictive model is used to calculate Markov mixture coefficients during a later operational prediction phase.