NeuroProstheses Research Laboratory

Departments of Biological Sciences and Biomedical Engineering  

Many of the current posited neural prosthetic interfaces require long-term, safe and effective neural recording and stimulation techniques.  These techniques often derive from the goal of either providing information to, or extracting information from functioning neural tissue.  However, the current techniques are limited in their ability to provide stable, high-throughput information channels for the lifetime of the neural prosthesis.  The goal of this research aim is to investigate advanced neural stimulation and recording techniques in animal models and to incorporate the results of these studies into a functioning human neural prosthesis.

Example of an input neural prosthesis.  In this movie the rat begins a trial by a press of the center lever.  Once the trial is started, the animal receives electrical microstimulation provided on one electrode of an array of microwires implanted in the auditory cortex.  The level of the stimulation is indicated by the text that appears on each trial.  The animal is rewarded for pressing the right lever for 90 microamp stimulation, and the left lever for 0 microamp stimulation (i.e. no stimulation).  Of interest are the trials where stimulation at an intermediate amplitude is given.

Example of an output neural prosthesis.  In this example the rat has previously been trained to listen for an auditory tone and then press a lever to obtain food.  The animal then underwent surgery to implant a microelectrode array into the primary motor cortex.  The sound that accompanies the movie is the electrical potential recorded on one channel of the array.  The "popping" noises are action potentials recorded from a nearby neuron.  The animal has now been taught a new task.  The rat is rewarded for rapidly increasing the rate of action potential generation by the neuron that we are recording from.  In the movie, first listen for the auditory tone.  Then pay careful attention to the rapidly occurring pops.  When the animal has successfully completed the task, a pellet of food is given and simultaneously the light in the cage dims slightly.

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Last modified: 04/04/07