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 An experimental Alzheimer's drug reverses genetic changes thought to spur the disease
04.05.2016 | Rockefeller University

nachricht Research points to a new treatment for pancreatic cancer
04.05.2016 | Purdue University

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: Nuclear Pores Captured on Film

Using an ultra fast-scanning atomic force microscope, a team of researchers from the University of Basel has filmed “living” nuclear pore complexes at work for the first time. Nuclear pores are molecular machines that control the traffic entering or exiting the cell nucleus. In their article published in Nature Nanotechnology, the researchers explain how the passage of unwanted molecules is prevented by rapidly moving molecular “tentacles” inside the pore.

Using high-speed AFM, Roderick Lim, Argovia Professor at the Biozentrum and the Swiss Nanoscience Institute of the University of Basel, has not only directly...

Im Focus: 2+1 is Not Always 3 - In the microworld unity is not always strength

If a person pushes a broken-down car alone, there is a certain effect. If another person helps, the result is the sum of their efforts. If two micro-particles are pushing another microparticle, however, the resulting effect may not necessarily be the sum their efforts. A recent study published in Nature Communications, measured this odd effect that scientists call “many body.”

In the microscopic world, where the modern miniaturized machines at the new frontiers of technology operate, as long as we are in the presence of two...

Im Focus: Tiny microbots that can clean up water

Researchers from the Max Planck Institute Stuttgart have developed self-propelled tiny ‘microbots’ that can remove lead or organic pollution from contaminated water.

Working with colleagues in Barcelona and Singapore, Samuel Sánchez’s group used graphene oxide to make their microscale motors, which are able to adsorb lead...

Im Focus: ORNL researchers discover new state of water molecule

Neutron scattering and computational modeling have revealed unique and unexpected behavior of water molecules under extreme confinement that is unmatched by any known gas, liquid or solid states.

In a paper published in Physical Review Letters, researchers at the Department of Energy's Oak Ridge National Laboratory describe a new tunneling state of...

Im Focus: Bionic Lightweight Design researchers of the Alfred Wegener Institute at Hannover Messe 2016

Honeycomb structures as the basic building block for industrial applications presented using holo pyramid

Researchers of the Alfred Wegener Institute (AWI) will introduce their latest developments in the field of bionic lightweight design at Hannover Messe from 25...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

The “AC21 International Forum 2016” is About to Begin

27.04.2016 | Event News

Soft switching combines efficiency and improved electro-magnetic compatibility

15.04.2016 | Event News

Grid-Supportive Buildings Give Boost to Renewable Energy Integration

12.04.2016 | Event News

 
Latest News

New fabrication and thermo-optical tuning of whispering gallery microlasers

04.05.2016 | Physics and Astronomy

Introducing the disposable laser

04.05.2016 | Physics and Astronomy

A new vortex identification method for 3-D complex flow

04.05.2016 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>