The Future of Medicine: Muscle-Powered Pacemaker

piezoelectric-pacemakerOver the past few decades, cardiac pacemakers have improved to the point that they have become a commonplace medical implant that have helped improve or save the lives of millions around the world. Unfortunately, the battery technology that is used to power these devices has not kept pace. Every seven years they need to be replaced, a process which requires further surgery.

To address this problem, a group of researchers from Korea Advanced Institute of Science and Technology (KAIST) has developed a cardiac pacemaker that is powered by harnessing energy from the body’s own muscles. The research team, headed by Professor Keon Jae Lee of KAIST and Professor Boyoung Joung, M.D. at Severance Hospital of Yonsei University, has created a flexible piezoelectric nanogenerator can keep a pacemaker running almost indefinitely.

piezoelectric_nanogeneratorTo test the device, Lee, Joung and their research team implanted the pacemaker into a live rat and watched as it produced electrical energy using nothing but small body movements. Based on earlier experiments with piezoelectric generator technology used by KAIST to produce a low-cost, large area version, the team created their new high-performance flexible nanogenerator from a thin film semiconductor material.

In this case, lead magnesium niobate-lead titanate (PMN-PT) was used rather than the graphene oxide and carbon nanotubes of previous versions. As a result, the new device was able to harvest up to 8.2 V and 0.22 mA of electrical energy as a result of small flexing motions of the nanogenerator. This voltage was sufficient enough to stimulate the rat’s heart directly.

pacemaker3The direct benefit of this experimental technology could be in the production and use of self-powered flexible energy generators that could increase the life of cardiac pacemakers, reduce the risks associated with repeated surgeries to replace pacemaker batteries, and even provide a way to power other implanted medical monitoring devices. As Professor Keon Jae Lee explains:

For clinical purposes, the current achievement will benefit the development of self-powered cardiac pacemakers as well as prevent heart attacks via the real-time diagnosis of heart arrhythmia. In addition, the flexible piezoelectric nanogenerator could also be utilized as an electrical source for various implantable medical devices.

Other self-powering experimental technologies for cardiac pacemakers have sought to provide energy from the beating of the heart itself, or from external sources, such as in light-controlled non-viral optogenetics.But the KAIST pacemaker appears to be the first practical version to demonstrate real promise in living laboratory animals and, with any luck, human patients in the not-too-distant future.

heart_patchesAnd while this does represent a major step forward in the field of piezoelectrics – a technology that could power everything from personal devices to entire communities by harnessing kinetic energy – it is also a boon for non-invasive medicine and energy self-sufficiency.

And be sure to check out this video of the pacemaker at work, courtesy of KAIST and the Severance Hospital of Yonsei University:


Sources: gizmag.com, circep.ahajournals.org, kaist.edu

The Future is Here: Brain to Brain Interfaces (Cont’d)

telepathyThis year is shaping up to be an exciting time for technology that enables people to communicate their thoughts via an electronic link. For the most part, this has involved the use of machinery to communicate a person’s thoughts to a machine – such as a prosthetic device. However, some researchers have gone beyond the field of brain-computer interfaces (BCIs) and have been making strides with brain-to-brain interfacing (BBI) instead.

Back in February, a research team in Natal Brazil, led by Miguel Nicolelis of Duke University, managed to create a link between the brains of two laboratory rats. In the experiment, an “encoder” rat in Natal was placed inside a “Skinner Box” where it would press a lever with an expectation of getting a treat in return.

BMIThe brain activity was then recorded and sent via electrical signal which was delivered to a second “decoder” rat which, though it was thousands of kilometers away, interpreted the signal and pressed a similar lever with a similar a expectation of reward. This developmental milestone was certainly big news, and has led to some even more impressive experiments since.

One of these comes from Harvard University, where scientists have developed a new, non-invasive interface that allowed a similar thought transfer to take place. Led by Seung-Schik Yoo, an assistant professor of radiology, the research team created a brain-to-brain interface (BBI) that allows a human controller to move a portion of a rat’s body just by thinking about it, all without invasive surgical implants.

BBIThe new technique takes advantage of a few advances being made in the field. These include focused ultrasound (FUS) technology, which delivers focused acoustic energy to a specific point. Ordinarily, this technology has used heat to destroy tumors and other diseased tissue in the deeper reaches of the brain.  Yoo’s team, however, has found that a lower-intensity blast can be used to stimulate brain tissue without damaging it.

In terms of the interface, a human controller was hooked up to an EEG-based BCI while the rat is hooked up to an FUS-based computer-to-brain interface (CBI). The human subject then viewed an image of a circle flashing in a specific pattern which generated electrical brain activity in the same frequency. When the BCI detected this activity, it sent a command to the CBI, which in turn sends FUS into the region of the rat’s brain that controls its tail, causing it to move.

MMIUsing six different human subjects and six different rat subjects, the team achieved a success rate of 94 percent, with a time delay of 1.59 ± 1.07 seconds between user intention and the rat’s response. Granted, it might not be quite the pinnacle of machine-powered telepathy, and the range of control over the animal test subject was quite limited. Still, the fact that two brains could be interfaced, and without the need for electrodes, is still a very impressive feat.

And of course, it raises quite a few possibilities. If brain-to-brain interfaces between humans and animals are possible, just what could it mean for the helper animal industry? Could seeing eye dogs be telepathically linked to their animals, thus able to send and receive signals from them instantaneously? What about butler monkeys? Could a single thought send them scurrying to the kitchen to fetch a fresh drink?

Who knows? But the fact that it could one day be possible is both inspiring and frightening!

Source: news.cnet.com