Methods and associated neural prosthetic devices for bridging brain areas to improve function

Abstract

Methods for bridging brain sites between which there is substantially no effective communication, and associated neural prosthetic devices, are provided. A neural spike in a first neural site in a subject is detected, and a stimulus to a second neural site in the subject is delivered within a defined period of time after the detection of the neural spike, wherein there is substantially no effective communication between the first and second neural sites. The method forms an artificial bridge between the two neural sites, and establishes lasting communication between the two sites. The present disclosure provides, among other things, a neural prosthetic device comprising an integrated circuit that comprises a recording front-end comprising a plurality of recording channels; a processor unit; and a stimulus delivering back-end comprising a plurality of stimulation channels.

What is claimed is: 
     
         1 . A method comprising:
 detecting a neural spike in a first neural site in a subject; and   delivering a stimulus to a second neural site in the subject within a defined period of time after the detection of the neural spike, wherein there is substantially no effective communication between the first and second neural sites.   
     
     
         2 . The method of  claim 1  wherein the first neural site, the second neural site, or both are located in a cortical region of the subject. 
     
     
         3 . The method of  claim 1  wherein the first neural site, the second neural site, or both are located in the spinal cord of the subject. 
     
     
         4 . The method of  claim 1  wherein the stimulus is an electrical pulse. 
     
     
         5 . The method of  claim 4  wherein the electrical pulse is monophasic or biphasic. 
     
     
         6 . The method of  claim 1  wherein delivering the stimulus occurs less than 5 ms after a neural spike is detected in the first neural site or less than 1000 ms after a neural spike is detected in the first neural site. 
     
     
         7 . The method of  claim 1  further comprising:
 using a neural prosthetic device to deliver the stimulus to the second neural site, wherein the neural prosthetic device comprises an integrated circuit that comprises: a recording front-end comprising a plurality of recording channels, a processor unit, and a stimulus delivering back-end comprising a plurality of stimulation channels. 
 
     
     
         8 . The method of  claim 1  wherein the first neural site and the second neural site are in different functional areas of the cortex. 
     
     
         9 . The method of  claim 1  wherein the subject has an injury as a result of a stroke, a traumatic brain injury, a neurosurgical resection, a tumor, or epilepsy. 
     
     
         10 . The method of  claim 1  continuing the detecting and delivering to a selected stage of functional recovery. 
     
     
         11 . The method of  claim 10  wherein the selected stage of functional recovery is reconnection of fibers, creation of a functional connection, or functional recovery of the subject. 
     
     
         12 . A method comprising:
 detecting a neural spike in a first neural site;   using a neural prosthetic device comprising a recording front-end, a processor unit, and a stimulus delivering back-end to deliver an electrical stimulus to a second neural site within a defined period of time after the detection of the neural spike; and   allowing the neural prosthetic device to provide an effective communication bridge between the first and second neural sites,   wherein the first neural site and the second neural site are located within a subject having a brain injury in which there is substantially no effective communication between the first neural site and the second neural site.   
     
     
         13 . The method of  claim 12 , wherein the first neural site and the second neural site are in different functional areas of the cortex. 
     
     
         14 . The method of  claim 12 , continuing the detecting and delivering to a selected stage of functional recovery. 
     
     
         15 . The method of  claim 14 , wherein the selected stage of functional recovery is reconnection of fibers, creation of a functional connection, or functional recovery of the subject. 
     
     
         16 . A neural prosthetic device comprising:
 a recording electrode;   an integrated circuit that comprises:
 a recording front-end comprising a plurality of recording channels, wherein the recording front-end is communicatively coupled to the recording electrode according to a plug-and-play configuration; and 
 a processor unit comprising a spike discriminator and decision circuitry, the processor unit configured to:
 detect a first neural spike in a first channel of the plurality of recording channels at a first time value, 
 detect a second neural spike in a second channel of the plurality of recording channels at a second time value, and 
 compare the first time value of the first neural spike from the first channel to the second time value of the second neural spike from the second channel, and 
 if the first time value and the second time value meet a predetermined criterion, trigger a delivery of a stimulus. 
 
   
     
     
         17 . The device of  claim 16 , wherein the recording electrode is at least partially comprised of iridium and either silicon or tungsten. 
     
     
         18 . The device of  claim 16 , wherein a flexible polyimide interconnect is used to communicatively couple the recording front-end to the recording electrode. 
     
     
         19 . The device of  claim 16 , wherein the device further comprises a radio-frequency transmitter that is usable to transmit data to an external radio-frequency receiver, and wherein the processor unit is further configured to collect and locally store data prior to the data being transmitted by the radio-frequency transmitter. 
     
     
         20 . The device of  claim 16 , wherein the device further comprises:
 a stimulation electrode that is communicatively coupled to the stimulus delivering back-end, the stimulation electrode being comprised of iridium oxide and either silicon or tungsten, and   a plurality of dc-blocking capacitors that are placed in series with the stimulation channels and that are usable to restrict dc current flow.