Detecting neuronal action potentials using a sparse signal representation

A method for detecting neuronal action potential signals from tissue responding to electrical stimulation signals, and providing stimulation to address hearing impairment, the method comprising:

• providing stimulation pulses, via electrodes of a cochlear implant system, to neural tissue and detecting a tissue response measurement signal;
• transmitting the tissue response measurement signal to a computer;
• using the computer to perform steps of:
• accessing a sparse signal space model for a set of tissue response recordings, the sparse signal space model having a model signal space separable into a plurality of disjoint component manifolds including:
• a neural action potential (NAP) component manifold corresponding to tissue response to electrical stimulation signals,
• a stimulation artifact component manifold corresponding to artifacts due to the electrical stimulation signals,
• a source artifact component manifold corresponding to artifacts due to sources other than the electrical stimulation signals, and
• a noise artifact component manifold;
• and
• mapping the tissue response measurement signal into the model signal space to obtain a corresponding sparse signal representation;
• projecting the sparse signal representation onto the NAP component manifold to obtain a sparse NAP component representation;
• and
• when the sparse NAP component representation is greater than a minimum threshold value, reporting a detected NAP signal in the tissue response measurement signal;
• determining an operating parameter for the cochlear implant system based on the detected NAP signal;
• transmitting the operating parameter to the cochlear implant system;
• and
• providing, by the cochlear implant system, stimulation pulses to the electrodes, the pulses based, at least in part, on the operating parameter.