DHAKA: A patch of gold, just a few centimeters wide and light as a feather, could reveal your innermost thoughts and feelings.

This is the premise of Professor John Rogers' Biostamp. By attaching flexible, miniature sensors to the user's temple, he has been able to track brain waves in real time and transmit them as messages.

"Our prototypes can provide a variety of monitoring and stimulation functions," says materials scientist Rogers of the University of Illinois at Urbana Champaign. "We can pick up coordinated firing of neurons, and run that activity through a computer spelling interface, so that brainwaves pick letters out of a virtual keyboard display and type messages."

Previously, such signals could only be detected by using a full helmet of heavy electrodes, which required the patient's skin to be scrubbed, and could only be worn safely for a short time.

Rogers' patch is light enough to be almost imperceptible, allowing for lengthy use even outside of the lab, so that the equipment is trained to pick up signals more accurately.

The no-strings approach also eliminates background noise that obscures signals and creates positional uncertainty. For even greater accuracy, the Illinois team are using increasingly high-density electrodes that generate thousands of times more brain activity information.

The immediate targets are two ground-breaking medical applications. One is to measure the brain waves associated with seizures in epileptic patients, flagging up issues before the point of crisis. The other is to monitor sleep patterns for disorders and other insights, which had been impossible with the traditional heavy hardware.

Anytime, Anywhere

The brain is just the latest and most ambitious target. Since Rogers invented the Biostamp to great fanfare in 2011, it has been used all over the body to measure heartbeat, temperature and other vital signs. They have been adapted by Reebok to monitor the force of impacts in sport, by L'Oreal to track skin hydration, and the US military to monitor the condition of soldiers.

'Biocompatible' devices are even being tested inside the body. The emerging field of electroceuticals offers the possibility of treatment as well as diagnosis, using targeted electronic stimulation as an alternative to drugs, a potentially revolutionary approach that can be applied to many organ problems.

The Illinois researchers have inserted electronics into the pelvic nerve to address bladder dysfunction, and on the surface of the heart to play the role of advanced pacemaker. They have also engineered stamps to dissolve safely inside the body after a set period of time.

Trials are limited to rodents currently, while researchers work through the safety hurdles that would allow the technology to be used on humans. Rogers acknowledges some risk in introducing foreign elements to the body, but is convinced this represents the path forward.

"The history of electronics is about getting closer to the individual. At first it was a computer down the hall, followed by a desktop, then a laptop, a phone in your pocket and a watch on your wrist. Now it could be electronics integrated the skin, bioelectronics, and fully implantable devices. To go fully into the realm of integrated electronics makes sense to me."

Key to this progress is a paradigm shift in electronics from rigid boards to soft and flexible devices that the human body can accommodate, and the Biostamp represents several adaptability breakthroughs.

Rogers' team removed the boards from circuits, which allowed them to miniaturize the components to nanoscale for a comfortable wearing experience. They succeeded in creating a device that could retain form and function even when stretched out of shape, and is completely waterproof so it can work on or under the skin.

One feature that has been difficult to shrink and stretch is the power source. Batteries have not progressed as rapidly as electrodes, leaving Rogers with either a limited lifespan for the stamp, an innovation for wireless harnessing of energy, or even using the body as the fuel source.

"It comes down to how much power your device needs. We have used body motion. For implant devices on the heart there is a constant source of mechanical power that can generate microwatts. But for outside the body you have to think how continuous the mechanical energy would be. The motion of legs and arms is an option...it is continued research not a slam dunk answer."

Source: CNN

BDST: 0858 HRS, MAY 16, 2015
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