Neural stimulation system and method responsive to collateral neural activity

Abstract

A neural stimulation system responsive to collateral neural activity that may arise in association with a neural stimulation procedure includes a stimulation interface configured to deliver stimulation signals to a target neural population, a monitoring interface positioned to receive signals corresponding to a neural activity within the target neural population, a stimulus unit coupled to deliver stimulation singals to the stimulation interface, and a sensing unit coupled to the monitoring device and the stimulus unit. The neural stimulation procedure may be directed toward rehabilitating, restoring, and/or enhancing one or more neural functions by facilitating and/or effectuating a neuroplastic change or reorganization; and/or affecting a neurological condition that exists on a continuous or essentially continuous basis absent the stimulation procedure. The sensing unit determines whether evidence of an collateral neural activity exists, whereupon the stimulus unit attempts to abate the collateral neural activity.

1 . A neural stimulation system for neurostimulation of a patient, comprising:
 a first set of electrodes configured to be positioned upon a target neural population corresponding to a site at which neuroplasticity is occurring, a site at which neuroplasticity is expected to occur, and/or a site associated with neuropathic pain;   a monitoring device to receive signals corresponding to a neural activity within a portion of the target neural population, wherein the neural activity is related to an undesired collateral effect of stimulation of the target neural population;   a stimulus unit coupled to deliver stimuli to the first set of electrodes, the stimuli comprising a plurality of groups of pulses occurring according to a burst frequency, wherein (i) multiple pulses are generated within each respective group according to a pulse repetition frequency, (ii) adjacent groups within the plurality of groups are spaced apart from each other in time with a substantially quiescent period; and   a sensing unit coupled receive signals from the monitoring device.   wherein the sensing unit is further coupled to the stimulus unit and the stimulus unit is adapted to vary a burst characteristic of the stimuli in response to feedback from the sensing unit.   
     
     
         2 . The neural stimulation system of  claim 1  wherein the stimulus unit modifies a burst frequency of the stimuli in response to the feedback from the sensing unit. 
     
     
         3 . The neural stimulation system of  claim 1  wherein the stimulus unit modifies the pulse repetition frequency in response to the feedback from the sensing unit. 
     
     
         4 . The neural stimulation system wherein the stimulus unit and the sensing unit are adapted for implantation within the patient. 
     
     
         5 . The neural stimulation system of  claim 1  wherein the monitoring device comprises a second set of electrodes. 
     
     
         6 . The neural stimulation system of  claim 1 , wherein the monitoring device comprises a cerebral blood flow monitor. 
     
     
         7 . A method of reducing seizure activity during neural stimulation to treat a neural condition in a patient comprising:
 applying electrical stimuli to a target neural population within the patient by positioning at least a first set of electrodes in contact with the patient's dura matter or pia matter, the electrical stimuli directed to altering the neural condition other than a seizure, the electrical stimuli comprising a plurality of groups of pulses occurring according to a burst frequency, wherein (i) multiple pulses are generated within each respective group according to a pulse repetition frequency, (ii) adjacent groups within the plurality of groups are spaced apart from each other in time with a substantially quiescent period;   monitoring a parameter associated with seizure activity;   determining if seizure activity is present;   reducing seizure activity, if present, by performing modifying at least one burst characteristic of the electrical stimuli.   
     
     
         8 . The method of  claim 7  wherein the monitoring a parameter associated with seizure activity comprises monitoring an electrophysiological signal of the patient. 
     
     
         9 . The method of  claim 7  wherein the monitoring a parameter comprises monitoring cerebral blood flow. 
     
     
         10 . The method of  claim 7  wherein the neural condition comprises pain. 
     
     
         11 . The method of  claim 7  wherein the neural condition comprises a functional deficit. 
     
     
         12 . The method of  claim 7  wherein the reducing modifies the burst frequency of the stimuli in response to the feedback from the sensing unit. 
     
     
         13 . The method of  claim 7  wherein the reducing modifies the pulse repetition frequency in response to the feedback from the sensing unit.