Methods and apparatus for effectuating a change in a neural-function of a patient

Abstract

The present disclosure is directed generally to methods and apparatus for effectuating a change in a neural function of a patient. A method in accordance with a particular embodiment includes implanting an electrode at a cortical stimulation site selected to promote recovery of the affected neural-function, with the cortical stimulation site being at least proximate to the cortex. The method can further include estimating a threshold for the specific patient at which an electrical signal delivered via the implanted electrode directly triggers a neural reaction associated with the stimulation site in response to the delivered electrical signal, and electrically stimulating the cortical stimulation site by Passing an electrical current through the electrode.

1 . In a specific patient that has experienced a stroke, a method for recovering a neural-function affected by the stroke, comprising:
 implanting an electrode at a cortical stimulation site selected to promote recovery of the affected neural-function, the cortical stimulation site being at least proximate to the cortex;   estimating a threshold for the specific patient at which an electrical signal delivered via the implanted electrode directly triggers a neural reaction associated with the stimulation site in response to the delivered electrical signal; and   electrically stimulating the cortical stimulation site by passing an electrical current through the electrode.   
   
   
       2 . The method of  claim 1  wherein implanting the electrode comprises placing the electrode at least proximate to the dura mater at the cortex. 
   
   
       3 . The method of  claim 2  wherein electrically stimulating the cortical stimulation site comprises applying an electrical signal at a level less than the estimated threshold. 
   
   
       4 . The method of  claim 3  wherein the electrical signal is applied at less than 80% of the estimated threshold. 
   
   
       5 . The method of  claim 3  wherein the electrical signal is applied at less than 60% of the estimated threshold. 
   
   
       6 . The method of  claim 1  wherein implanting the electrode comprises positioning the electrode at the supplementary motor cortex anterior to a location of the stroke. 
   
   
       7 . The method of  claim 1  wherein electrically stimulating the cortical stimulation site comprises passing an anodic current through the electrode. 
   
   
       8 . The method of  claim 1  wherein electrically stimulating the cortical stimulation site comprises passing a cathodic current through the electrode. 
   
   
       9 . The method of  claim 1 , further comprising implanting a pulse generator in the patient away from the brain and connecting a lead to the pulse generator and the electrode. 
   
   
       10 . The method of  claim 1  wherein applying electrical stimulation comprises applying a signal having a voltage effective to raise an expected resting potential of a population of neurons at the stimulation site by at least approximately 10% of a difference between the expected resting potential and an action potential for the population of neurons. 
   
   
       11 . The method of  claim 1  wherein applying electrical stimulation comprises applying a signal having a voltage effective to raise an expected resting potential of a population of neurons at the stimulation site by at least approximately 60% of a difference between the expected resting potential and an action potential for the population of neurons. 
   
   
       12 . The method of  claim 1  wherein applying electrical stimulation comprises applying a signal having a voltage effective to raise an expected resting potential of a population of neurons at the stimulation site by at least approximately 10-80% of a difference between the expected resting potential and an action potential for the population of neurons. 
   
   
       13 . The method of  claim 1  wherein applying electrical stimulation comprises applying a signal having a frequency of approximately 40-200 HZ. 
   
   
       14 . The method of  claim 1  wherein applying electrical stimulation comprises applying a signal having a frequency of approximately 50 HZ.