Our last post about brain injuries discussed using bionic limbs to allow paralyzed individuals to move. Although the technology associated with such advanced bionics may be years away from commercial availability, researchers and victims of brain and spinal cord injury alike are excited about recent development.

A quadriplegic man from Pittsburgh was one of the first individuals to test the technology. He used his mind to control a robotic arm to give high fives and rub his girlfriend’s hand, and he said there were no words to describe being able to move his limbs after seven years of immobility.

The cutting-edge technology that may one day enable paralyzed individuals to control robotic limbs with their minds is fascinating, and it offers new possibilities to people who have suffered brain injuries or paralysis.

The way our brains and bodies work together to enable us to do things as simple as hold a cup of coffee or grasp a pencil is intricate and fascinating. When everything works the way it should, we often take that functionality for granted. Few of us think about the messages our brains are sending throughout our bodies, or that we are only able to complete those actions because neurons fire in patterns that send commands down the spinal cord and to the appropriate body part.

When an individual has suffered the sort of severe nerve damage associated with spinal cord injury, commands are no longer able to travel throughout the body. Similarly, if part of the brain is damaged, the ability of the brain to issue commands to the body can be severely impaired.

According to the lead researcher at the University of Pittsburgh, scientists hope to use a “brain-computer interface” (BCI), an array of electrodes that record electrical activity, as a way of bridging the brain-body communication gap or of allowing the brain to control replacement bionic limbs.

When BCIs are implanted, “signals move down through wires that tunnel under the skin and out by the collarbone,” where they are plugged into computers or robotic arms. While early research has been exciting, scientists have also found that over time, scar tissue may form on the brain or spinal cord that can impede these electrical signals. In order for the technology to be efficient long-term and commercially viable, researchers will likely need to convert the system to become wireless.

The scientific advances are fascinating, but there are still two main problems. First, the bionic limbs do not sense what they touch. As a result, it is difficult for the brain to know if it is applying the right amount of pressure. For example, is the hand holding the coffee cup tightly enough that it won’t fall, but lightly enough that it won’t shatter the glass?

The second problem is determining a way to fully integrate the bionic limb technology with the human body.

Regardless of the many challenges, the progress is promising, and research teams at the University of Pittsburgh and Duke University have already started tackling those problems.

Source: Bloomberg BusinessWeek, “Paralyzed man uses mind-powered robot arm to touch,” Lauran Neergaard, Oct. 10, 2011