Navigation Links
Ultrasound directed to the human brain can boost sensory performance
Date:1/12/2014

Whales, bats, and even praying mantises use ultrasound as a sensory guidance system and now a new study has found that ultrasound can modulate brain activity to heighten sensory perception in humans.

Virginia Tech Carilion Research Institute scientists have demonstrated that ultrasound directed to a specific region of the brain can boost performance in sensory discrimination. The study, published online Jan. 12 in Nature Neuroscience, provides the first demonstration that low-intensity, transcranial-focused ultrasound can modulate human brain activity to enhance perception.

"Ultrasound has great potential for bringing unprecedented resolution to the growing trend of mapping the human brain's connectivity," said William "Jamie" Tyler, an assistant professor at the Virginia Tech Carilion Research Institute, who led the study. "So we decided to look at the effects of ultrasound on the region of the brain responsible for processing tactile sensory inputs."

The scientists delivered focused ultrasound to an area of the cerebral cortex that processes sensory information received from the hand. To stimulate the median nerve a major nerve that runs down the arm and the only one that passes through the carpal tunnel they placed a small electrode on the wrist of human volunteers and recorded their brain responses using electroencephalography, or EEG. Then, just before stimulating the nerve, they began delivering ultrasound to the targeted brain region.

The scientists found that the ultrasound both decreased the EEG signal and weakened the brain waves responsible for encoding tactile stimulation.

The scientists then administered two classic neurological tests: the two-point discrimination test, which measures a subject's ability to distinguish whether two nearby objects touching the skin are truly two distinct points, rather than one; and the frequency discrimination task, a test that measures sensitivity to the frequency of a chain of air puffs.

What the scientists found was unexpected.

The subjects receiving ultrasound showed significant improvements in their ability to distinguish pins at closer distances and to discriminate small frequency differences between successive air puffs.

"Our observations surprised us," said Tyler. "Even though the brain waves associated with the tactile stimulation had weakened, people actually got better at detecting differences in sensations."

Why would suppression of brain responses to sensory stimulation heighten perception? Tyler speculates that the ultrasound affected an important neurological balance.

"It seems paradoxical, but we suspect that the particular ultrasound waveform we used in the study alters the balance of synaptic inhibition and excitation between neighboring neurons within the cerebral cortex," Tyler said. "We believe focused ultrasound changed the balance of ongoing excitation and inhibition processing sensory stimuli in the brain region targeted and that this shift prevented the spatial spread of excitation in response to stimuli resulting in a functional improvement in perception."

To understand how well they could pinpoint the effect, the research team moved the acoustic beam one centimeter in either direction of the original site of brain stimulation and the effect disappeared.

"That means we can use ultrasound to target an area of the brain as small as the size of an M&M," Tyler said. "This finding represents a new way of noninvasively modulating human brain activity with a better spatial resolution than anything currently available."

Based on the findings of the current study and an earlier one, the researchers concluded that ultrasound has a greater spatial resolution than two other leading noninvasive brain stimulation technologies transcranial magnetic stimulation, which uses magnets to activate the brain, and transcranial direct current stimulation, which uses weak electrical currents delivered directly to the brain through electrodes placed on the head.

"Gaining a better understanding of how pulsed ultrasound affects the balance of synaptic inhibition and excitation in targeted brain regions as well as how it influences the activity of local circuits versus long-range connections will help us make more precise maps of the richly interconnected synaptic circuits in the human brain," said Wynn Legon, the study's first author and a postdoctoral scholar at the Virginia Tech Carilion Research Institute. "We hope to continue to extend the capabilities of ultrasound for noninvasively tweaking brain circuits to help us understand how the human brain works."

"The work by Jamie Tyler and his colleagues is at the forefront of the coming tsunami of developing new safe yet effective noninvasive ways to modulate the flow of information in cellular circuits within the living human brain," said Michael Friedlander, executive director of the Virginia Tech Carilion Research Institute and a neuroscientist who specializes in brain plasticity. "This approach is providing the technology and proof of principle for precise activation of neural circuits for a range of important uses, including potential treatments for neurodegenerative disorders, psychiatric diseases, and behavioral disorders. Moreover, it arms the neuroscientific community with a powerful new tool to explore the function of the healthy human brain, helping us understand cognition, decision-making, and thought. This is just the type of breakthrough called for in President Obama's BRAIN Initiative to enable dramatic new approaches for exploring the functional circuitry of the living human brain and for treating Alzheimer's disease and other disorders."

A team of Virginia Tech Carilion Research Institute scientists including Tomokazu Sato, Alexander Opitz, Aaron Barbour, and Amanda Williams, along with Virginia Tech graduate student Jerel Mueller of Raleigh, N.C. joined Tyler and Legon in conducting the research.

In addition to his position at the institute, Tyler is an assistant professor of biomedical engineering and sciences at the Virginia Tech-Wake Forest University School of Biomedical Engineering and Sciences. In 2012, he shared a Technological Innovation Award from the McKnight Endowment for Neuroscience to work on developing ultrasound as a noninvasive tool for modulating brain activity.

"In neuroscience, it's easy to disrupt things," said Tyler. "We can distract you, make you feel numb, trick you with optical illusions. It's easy to make things worse, but it's hard to make them better. These findings make us believe we're on the right path."


'/>"/>

Contact: Paula Byron
pbyron@vt.edu
540-526-2027
Virginia Tech
Source:Eurekalert  

Related biology news :

1. Trial to test using ultrasound to move kidney stones
2. Ultrasound, nanoparticles may help diabetics avoid the needle
3. Ultrasound patch heals venous ulcers in human trial
4. UF researcher shows hawkmoths use ultrasound to combat bats
5. Measuring ultrasound for better treatment of muscle injuries
6. Texas A&M research contributes to improved ultrasound imaging
7. Ultrasound reveals autism risk at birth
8. Springer will collaborate with the Italian Society for Ultrasound in Medicine and Biology
9. Neuroscientists prove ultrasound can be tweaked to stimulate different sensations
10. Preclinical studies use specialized ultrasound to detect presence of cancer
11. Acoustic tweezers capture tiny creatures with ultrasound
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Ultrasound directed to the human brain can boost sensory performance
(Date:11/24/2016)... Cercacor today introduced Ember TM Sport ... non-invasively measure hemoglobin, Oxygen Content, Oxygen Saturation, Perfusion ... in approximately 30 seconds. Smaller than a smartphone, using ... to key data about their bodies to help monitor ... Hemoglobin carries oxygen to muscles. When hemoglobin ...
(Date:11/19/2016)... 18, 2016 Securus Technologies, a leading provider ... safety, investigation, corrections and monitoring, announced today that it ... to have an independent technology judge determine who has ... high tech/sophisticated telephone calling platform, and the best customer ... do most of what we do – which clearly ...
(Date:11/15/2016)... , Nov. 15, 2016  Synthetic Biologics, ... developing therapeutics focused on the gut microbiome, today ... of 25,000,000 shares of its common stock and ... stock at a price to the public of ... to Synthetic Biologics from the offering, excluding the ...
Breaking Biology News(10 mins):
(Date:11/30/2016)... /PRNewswire/ -  Equicare Health Inc ., the leading supplier ... one of the top 100 companies in the 2016 ... distinguishes the top digital health companies across the globe. ... this year continually upgrading our product with the ongoing ... team," says Len Grenier , CEO of Equicare ...
(Date:11/30/2016)... , 30. November 2016   Merck ... heute die Unterzeichnung einer Reihe von Vereinbarungen ... wird Evotec AG Screeningleistungen für Mercks Palette ... Der Zugriff auf diese Bibliotheken in Kombination ... einen schnelleren Weg zur Ermittlung und Erforschung ...
(Date:11/30/2016)... ... November 30, 2016 , ... SSCI, the established leader ... the implications of the latest FDA guidance on pharmaceutical cocrystals as drug substance ... Cambridge, MA. , The event follows the successful November 15th event that ...
(Date:11/30/2016)... ... November 30, 2016 , ... On 28 November 2016, ... for four elements: nihonium (Nh), moscovium (Mc), tennessine (Ts), and oganesson (Og), respectively ... review, the names earlier proposed by the discoverers have been approved by the IUPAC ...
Breaking Biology Technology: