It’s an easy and obvious comparison, seeing as how at least someone we know probably owns one of those ubiquitous “activity trackers.”
Even Mrs. Dittman – sometimes the focus of my playful “Luddite” barbs – has one of those wireless-enabled wearable devices.
But measuring data such as the number of steps walked or climbed, heart rate, quality of sleep, and other personal metrics is piker tech compared with what engineers at UC Berkeley are up to.
In a paper published on August 3, 2016, by the journal Neuron, the team describes a technology that goes beyond “wearable” and is, instead, “implantable.”
Michel Maharbiz, Jose Carmena, and their colleagues are developing dust-sized, wireless sensors that can be inserted into the brain, muscles, and intestines to provide real-time monitoring.
And “neural dust” could someday be used to control prosthetics or, as the foundation for “electroceuticals,” to treat epilepsy, boost the immune system, or help ease inflammation.
It’s a pretty big step in the emerging field of bioelectronic medicine, a discipline that seeks to find methods for deciphering and modulating electrophysiological activity in the body in order to attain therapeutic effects at target organs.
What these guys have done eliminates the need for wires in machinery used to gather information from peripheral nerves and muscles. Wires create problems where devices are intended for long-term use.
Implantable electrodes in current use wear out within one or two years. And they’re connected to wires that pass through holes in the skull.
Wireless sensors – one, two, or even a hundred – can be sealed inside the body, eliminating risk of infection and unintended movement of the electrodes.
They’ve also overcome scalability problems associated with other emerging wireless technologies.
The cool thing is they’ve made a revolutionary advance based on pretty pedestrian technology – ultrasound.
Their 2013 study “demonstrated that the fundamental physics of ultrasound allowed for very, very small implants that could record and communicate neural data,” says Maharbiz.
And now they’ve created a system tying it all together.
Here’s the summary of their paper, “Wireless Recording in the Peripheral Nervous System with Ultrasonic Neural Dust”:
“The emerging field of bioelectronic medicine seeks methods for deciphering and modulating electrophysiological activity in the body to attain therapeutic effects at target organs. Current approaches to interfacing with peripheral nerves and muscles rely heavily on wires, creating problems for chronic use, while emerging wireless approaches lack the size scalability necessary to interrogate small-diameter nerves. Furthermore, conventional electrode-based technologies lack the capability to record from nerves with high spatial resolution or to record independently from many discrete sites within a nerve bundle. Here, we demonstrate neural dust, a wireless and scalable ultrasonic backscatter system for powering and communicating with implanted bioelectronics. We show that ultrasound is effective at delivering power to mm-scale devices in tissue; likewise, passive, batteryless communication using backscatter enables high-fidelity transmission of electromyogram (EMG) and electroneurogram (ENG) signals from anesthetized rats. These results highlight the potential for an ultrasound-based neural interface system for advancing future bioelectronics-based therapies.”
According to Maharbiz, an associate professor of electrical engineering and computer sciences at Berkeley, “The long-term prospects for neural dust are not only within nerves and the brain, but much broader.”
He explained to the website Berkeley News that, “Having access to in-body telemetry has never been possible because there’s been no way to put something super tiny super deep. But now I can take a speck of nothing and park it next to a nerve or organ, your GI tract, or a muscle and read out the data.”
Maharbiz and his team tested the first-generation sensors – which are about 3 millimeters long and 1 millimeter by 1 millimeter in cross section – in laboratory rats.
A piezoelectric crystal… converts ultrasound vibrations from outside the body into electricity to power a tiny, onboard transistor that is in contact with a nerve or muscle fiber.
A voltage spike in the fiber alters the circuit and the vibration of the crystal, which changes the echo detected by the ultrasound receiver, typically the same device that generates the vibrations.
The slight change, called backscatter, allows them to determine the voltage, reports Berkeley News.
Next-generation sensors are about the size of a very large grain of sand.
Berkeley News tells us in the 2013 paper, “The researchers estimated that they could shrink the sensors down to a cube 50 microns on a side – about two-thousandths of an inch, or half the width of a human hair.”
At that size, the sensors could be placed right next to a few nerve axons “and continually record their electrical activity.”
The technology isn’t there yet for the 50-micron target, but the sensors are already small enough for use in the peripheral nervous system – for example, to aid in bladder control or appetite suppression.
Soon enough, a paraplegic will be able to control a robotic arm with a simple, permanent electrode implanted in his brain.
The Russell 2000 Index continues to rally, pushing out to 1,231.30 as of Friday’s close.
The CBOE Volatility Index (VIX) slid to one-year lows last week.
The U.S. added 255,000 jobs in July, according to the Labor Department’s report on nonfarm payrolls, beating a consensus forecast of 180,000. June’s blockbuster payroll number was revised higher, to 292,000. And wages grew by 2.7%, a post-crisis high. The unemployment rate was unchanged at 4.9%.
But according to Mitsubishi UFJ strategist John Herrmann, the jobs headline overstates the strength of payroll data. Unadjusted data show a “middling report” that’s “nowhere as strong as the headline” and adds that private payrolls unadjusted were 85,000 in July, versus a seasonally adjusted 217,000. In Herrmann’s view, the government applied a “very benign seasonal adjustment factor upon private payrolls to transform a soft private payroll gain into a strong gain.”
According to Scientific American, “For the first time, cosmologists have used the full power of Albert Einstein’s general theory of relativity to perform detailed calculations of the universe’s evolution.”
Editorial Director, Wall Street Daily