Sensory Motor Transformation in Human Cortex
Physicians and researchers at Caltech, Keck Hospital of USC, and Rancho Los Amigos are conducting a paid research study to develop a brain-machine interface (or BMI) for persons with spinal cord injuries. A BMI records and interprets brain activity in order to control an external device such as a computer cursor or robotic limb. Signals can also be written into the brain with small amounts of electrical stimulation. In this way, a BMI could provide touch feedback from external devices.
Participants in this study will receive a BMI implant and practice using it over one year.
The BMI device in this study involves placing electrode arrays smaller than a penny into areas of the brain known to plan hand grasps and arm movements. These areas would normally send the signals that produce actual body movements. By recording these signals and sending them to a computer instead, we can convert intended actions into actual movements of external devices such as a computer cursor or a robotic limb.
As part of the BMI device, additional electrode arrays will be placed in areas of the brain that process touch sensations. By giving very small electrical stimulation in this area we hope to produce sensations in the hand and arm that can mimic touch feedback. For example, the device could produce a sensation to "feel" when a robot hand makes contact with an object.
What will happen in this Study?
We have received approval from the U.S. Food and Drug Administration (FDA) to implant the BMI device for a period of one year (additional years are possible). If you participate in this study, you will undergo two surgeries: one to place the device at the beginning of the study, and one to remove the device at the end of the study.
You will be paid for your participation in the study. Specific payments will be made to you for the time in the hospital for both of the surgeries, as well as each study session you attend.
The BMI device consists of two electrode arrays for recording and two electrode arrays for stimulation which will be placed on the surface of the brain through an opening in the skull. The wires for the arrays will be attached to three connectors that are fixed to the skull and protrude through the scalp. These connectors will be used to send signals to and from the computer system.
After you have recovered from the placement surgery, you will train with study personnel to learn how to use the BMI. Training sessions may occur up to five days per week, and we will work with you to determine the best schedule. During these training sessions, you will learn how to use your brain activity to control simple games on the computer or external devices like a robotic hand or arm. Learning to control the BMI will require consistent practice and effort, just as with any new skill! You will start with simple tasks and gradually move to more complicated activities.
If you participate in the study, you are not under any contract to remain in the study, and you may withdraw at any time. Likewise, if you wish to continue after the first year, study doctors and scientists will discuss this possibility with you. However, the BMI device is not intended to be permanent. When you exit the study, the device will be removed. All medical care related to the BMI device (implant and explant surgeries, follow-up medical appointments, etc.) will be provided by the study at no cost to you. Your experience with the device may differ from previously reported experiences of BMI users.