Providing Closed Loop Cortical Control of Extracorporeal Devices to Patients With Quadriplegia

This research study is being conducted to develop a brain controlled medical device, called a
brain-machine interface. The device will provide people with a spinal cord injury some
ability to control an external device such as a computer cursor or robotic limb by using
their thoughts along with sensory feedback.

Development of a brain-machine interface is very difficult and currently only limited
technology exists in this area of neuroscience. Other studies have shown that people with
high spinal cord injury still have intact brain areas capable of planning movements and
grasps, but are not able to execute the movement plans. The device in this study involves
implanting very fine recording electrodes into areas of the brain that are known to create
arm movement plans and provide hand grasping information and sense feeling in the hand and
fingers. These movement and grasp plans would then normally be sent to other regions of the
brain to execute the actual movements. By tying into those pathways and sending the movement
plan signals to a computer instead, the investigators can translate the movement plans into
actual movements by a computer cursor or robotic limb.

A key part of this study is to electrically stimulate the brain by introducing a small amount
of electrical current into the electrodes in the sensory area of the brain. This will result
in the sensation of touch in the hand and/or fingers. This stimulation to the brain will
occur when the robotic limb touches the object, thereby allowing the brain to "feel" what the
robotic arm is touching.

The device being used in this study is called the Neuroport Array and is surgically implanted
in the brain. This device and the implantation procedure are experimental which means that it
has not been approved by the Food and Drug Administration (FDA). One Neuroport Array consists
of a small grid of electrodes that will be implanted in brain tissue and a small cable that
runs from the electrode grid to a small hourglass-shaped pedestal. This pedestal is designed
to be attached to the skull and protrude through the scalp to allow for connection with the
computer equipment. The top portion of the pedestal has a protective cover that will be in
place when the pedestal is not in use. The top of this pedestal and its protective cover will
be visible on the outside of the head. Three Neuroport Arrays and pedestals will be implanted
in this study so three of these protective covers will be visible outside of the head. It
will be possible to cover these exposed portions of the device with a hat or scarf.

The investigators hope to learn how safe and effective the Neuroport array plus stimulation
is in controlling computer generated images and real world objects, such as a robotic arm,
using imagined movements of the arms and hands.