tomorrowtechtoday.com

Bionics, for most of us, would bring up images of Luke Skywalker and his robotic hand from Star Wars. If you’re as old as me (in your 40s) you can probably remember Steve Austin, the Six Million Dollar Man.  Being able to bend solid steel bars and run as fast as a speeding car he was the epitome of cutting edge technology (be it sci-fi technology) of the 1970’s.

Today, Bionics, while not in the same league as Steve Austin, has progressed to an amazing level and has truly improved the lives of many people.

The hardware side of things is an awesome advance in itself, but that’s not the whole picture. While creating robotic limbs that mimic the movements of the originals are awesome. The real breakthroughs however lie with the Brain-Machine Interfaces. (BMI’s)

Most of the functions of our body are driven by electrical currents from a part of our brain called the motor cortex. The motor cortex sends out the electrical impulses down the spinal cord through nerves into our muscles. These electrical impulses cause our muscles to move. Raise and lower our arm, walk or run and a multitude of other seemingly simply movements we take for granted each day. Brain-Machine Interfaces replicate this system, and are what makes Bionics possible.

BMI’s generally fit into two categories; non-invasive and invasive. The EEG (Electroencephalograph) is the earliest non-invasive BMI, measuring the huge groups of neurons through voltage differences between different parts of the brain. The EEG measures these differences by placing a number of electrodes on the scalp, the ensuing signals being converted to a digital signal and feed into a computer. This type of BMI has achieved success in subjects controlling cursors on a computer screen and playing computer games. It has also been reported that using an EEG a severely disabled tetraplegic patient was able to grasp an object using his paralysed hand.  The patient-generated brain waves were detected by the EEG and converted into external electrical muscle stimulation, allowing the contraction of the muscles and movement of the paralysed hand.

Invasive BMI’s hold a greater promise of returning near normal control to patients with severed spinal cords injuries and amputee’s with bionic limbs. Invasive BMI’s are implanted directly into the patient’s brain. Being more sensitive and in direct contact with appropriate region of the motor cortex the implanted electrodes have a greater resolution and are far more accurate in measuring the electrical impulses.

In 2003, Jesse Sullivan, a 53 year old electrical technician who lost both arms in a work accident, was the first to be fitted with a bionic arm. The nerves that would usually send impulses to his arm muscles were surgically relocated to his chest. Electrodes were them implanted to pick up the signals from these nerves and feed them into a computer. The impulses were then converted into digital signal which controlled the bionic arms.  View video

One of the next great challenges for bionic limbs is to make them “feel”, creating the ability for the limb to send information back to the brain.  Creating a sense of touch, hot and cold as well as being sensitive to the amount of pressure being applied.

Alongside the bionic limb, progress is being made in both restoring sight to the blind and hearing to the deaf. Sight is being restored via a small camera mounted in the patient’s glasses feeding the image to an electronic chip. This is implanted on the retina of the eye. Hearing is being restored by a cochlear implant where tiny wires are inserted to the cochlea and a microphone fixed to the skull.

We are living in a brave new world, one that brings hope to those who through birth or by accident have lost function to parts of their body. Let’s hope so.