Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Neuroscientists prove ultrasound can be tweaked to stimulate different sensations

07.12.2012
Discovery carries implications for diagnosing, treating people with neuropathy, including more than half of those with Type 2 diabetes

A century after the world's first ultrasonic detection device – invented in response to the sinking of the Titanic – Virginia Tech Carilion Research Institute scientists have provided the first neurophysiological evidence for something that researchers have long suspected: ultrasound applied to the periphery, such as the fingertips, can stimulate different sensory pathways leading to the brain.

And that's just the tip of the iceberg. The discovery carries implications for diagnosing and treating neuropathy, which affects millions of people around the world.

"Ideally, neurologists should be able to tailor treatments to the specific sensations their patients are feeling," said William "Jamie" Tyler, an assistant professor at the Virginia Tech Carilion Research Institute, who led the study published this week in PLOS ONE. "Unfortunately, even with today's technologies, it's difficult to stimulate certain types of sensations without evoking others. Pulsed ultrasound allows us to selectively activate functional subsets of nerve fibers so we can study what happens when you stimulate, for example, only the peripheral fibers and central nervous system pathways that convey the sensation of fast, sharp pain or only those that convey the sensation of slow, dull, throbbing pain."

An estimated 20 million people in the United States alone suffer from neuropathy, a collection of nervous system disorders that may cause pain, numbness, and sensations of burning, itching, and tingling. One of the most common causes of neuropathy is Type 2 diabetes. Autoimmune disorders, such as lupus and Guillain-Barré syndrome; traumatic nerve injury; genetic abnormalities; movement disorders; and infectious diseases such as HIV/AIDS, Lyme disease, and leprosy can also trigger neuropathy.

"Neuropathy involves both motor nerves that control how muscles move and sensory nerves that receive sensations such as heat, pain, and touch," Tyler said. "So clinicians may use, for example, small resonator devices to vibrate the skin or lasers to heat the surface of the skin. But we wanted to develop a method that could activate superficial and deep mechanical receptors, thermal receptors, and even combinations of both. So we used pulsed ultrasound."

In the 1970s, a group of Soviet scientists made observations that ultrasound could stimulate distinct neural pathways, but their evidence was only anecdotal, with subjects merely describing sensations of heat, pain, or vibration. In the current study, the researchers used functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) to provide physiological proof of those early observations.

Study participants rested their index fingers on ultrasound transducers while having their brain activity monitored with fMRI and EEG. The scientists found that they could stimulate specific somatosensory pathways just by tweaking the ultrasound waveforms.

Tyler believes the finding has important implications for pain diagnosis.

"Current methods of diagnosing and characterizing pain can sometimes seem archaic," Tyler said. "To measure pain through mechanical stimulation, for example, physicians might touch the skin with nylon monofilaments known as von Frey hairs, or they'll stroke the skin with a paintbrush. For thermal sensory testing, patients may even plunge their hands into ice water until the pain becomes too great. We're hoping to provide physicians with more precise diagnostic tools."

Better diagnostics will lead to better therapeutics, said neuroscientist Michael Friedlander, executive director of the Virginia Tech Carilion Research Institute.

"By combining pulsed ultrasound with the technologies to record brain activity, Jamie Tyler and his colleagues are taking this to a whole new level of diagnostics," Friedlander said. "And the diagnostics will ultimately drive the therapeutics. This research is a great example of how new technologies can be adapted for real-world, patient-centered diagnoses and treatments."

Tyler noted the discovery could lead to other applications.

"Ultrasound transducers could be fashioned into flexible, flat insoles to provide sensory stimulation to people who have lost sensation in their feet, including the elderly, who are at such risk of falling," he said. "Surgical instruments could provide tactile feedback to surgeons in training. And I can imagine countless applications for consumer electronics. Users already rely on two-way somatosensory communication with their devices, and peripheral stimulation using ultrasound could add new dimensionalities to this communication."

Researchers will now investigage which ultrasound parameters stimulate which types of nerve fibers or receptors. Tyler also hopes to study people with Type 2 diabetes who have not yet developed neuropathy, with the ultimate goal of providing clues to treating or even preventing the pain associated with the condition.

This research may get a boost from a discovery that surprised Tyler during the PLOS ONE study.

"One thing we didn't expect is that some brain scans showed activation of pain pathways, yet the volunteers reported feeling no discomfort," Tyler said. "That's an intriguing finding. Though we don't yet know its full implications, being able to activate classic pain pathways without inducing perceptual pain can help us understand how the brain processes pain."

A team of Virginia Tech Carilion Research Institute scientists – including Wynn Legon, Abby Rowlands, Alexander Opitz, and Tomokazu Sato – joined Tyler in conducting the research. In addition to his position at the institute, Tyler is an assistant professor of biomedical engineering and science at the Virginia Tech–Wake Forest University School of Biomedical Engineering and Sciences. He recently shared a McKnight Technological Innovations in Neuroscience Award for work in using ultrasound to develop noninvasive approaches to modulating the activity of select circuits in the brain.

Paula Byron | EurekAlert!
Further information:
http://www.vt.edu

More articles from Health and Medicine:

nachricht Using DNA origami to build nanodevices of the future
31.08.2015 | Institute for Integrated Cell-Material Sciences at Kyoto University

nachricht An ounce of prevention: Research advances on 'scourge' of transplant wards
28.08.2015 | University of Wisconsin-Madison

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Increasingly severe disturbances weaken world's temperate forests

Longer, more severe, and hotter droughts and a myriad of other threats, including diseases and more extensive and severe wildfires, are threatening to transform some of the world's temperate forests, a new study published in Science has found. Without informed management, some forests could convert to shrublands or grasslands within the coming decades.

"While we have been trying to manage for resilience of 20th century conditions, we realize now that we must prepare for transformations and attempt to ease...

Im Focus: OU astrophysicist and collaborators find supermassive black holes in quasar nearest Earth

A University of Oklahoma astrophysicist and his Chinese collaborator have found two supermassive black holes in Markarian 231, the nearest quasar to Earth, using observations from NASA's Hubble Space Telescope.

The discovery of two supermassive black holes--one larger one and a second, smaller one--are evidence of a binary black hole and suggests that supermassive...

Im Focus: What would a tsunami in the Mediterranean look like?

A team of European researchers have developed a model to simulate the impact of tsunamis generated by earthquakes and applied it to the Eastern Mediterranean. The results show how tsunami waves could hit and inundate coastal areas in southern Italy and Greece. The study is published today (27 August) in Ocean Science, an open access journal of the European Geosciences Union (EGU).

Though not as frequent as in the Pacific and Indian oceans, tsunamis also occur in the Mediterranean, mainly due to earthquakes generated when the African...

Im Focus: Self-healing landscape: landslides after earthquake

In mountainous regions earthquakes often cause strong landslides, which can be exacerbated by heavy rain. However, after an initial increase, the frequency of these mass wasting events, often enormous and dangerous, declines, in fact independently of meteorological events and aftershocks.

These new findings are presented by a German-Franco-Japanese team of geoscientists in the current issue of the journal Geology, under the lead of the GFZ...

Im Focus: FIC Proteins Send Bacteria Into Hibernation

Bacteria do not cease to amaze us with their survival strategies. A research team from the University of Basel's Biozentrum has now discovered how bacteria enter a sleep mode using a so-called FIC toxin. In the current issue of “Cell Reports”, the scientists describe the mechanism of action and also explain why their discovery provides new insights into the evolution of pathogens.

For many poisons there are antidotes which neutralize their toxic effect. Toxin-antitoxin systems in bacteria work in a similar manner: As long as a cell...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Networking conference in Heidelberg for outstanding mathematicians and computer scientists

20.08.2015 | Event News

Scientists meet in Münster for the world’s largest Chitin und Chitosan Conference

20.08.2015 | Event News

Large agribusiness management strategies

19.08.2015 | Event News

 
Latest News

Production research by Fraunhofer IAO honored with three awards at the ICPR 2015

31.08.2015 | Awards Funding

Single-Crystal Phosphors Suitable for Ultra-Bright, High-Power White Light Sources

31.08.2015 | Materials Sciences

Manchester Team Reveal New, Stable 2D Materials

31.08.2015 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>