Sound Waves To Control Brain Cells Through Sonogenetics Discovered

Salk scientists have developed a new way to selectively activate brain, heart, muscle and other cells using ultrasonic waves. The new technique, dubbed sonogenetics, has some similarities to the burgeoning use of light to activate cells in order to better understand the brain.

This new method--which uses the same type of waves used in medical sonograms--may have advantages over the light-based approach--known as optogenetics--particularly when it comes to adapting the technology to human therapeutics. It was described September 15, 2015 in the journal Nature Communications.

"Light-based techniques are great for some uses and I think we're going to continue to see developments on that front," says Sreekanth Chalasani, an assistant professor in Salk's Molecular Neurobiology Laboratory and senior author of the study. "But this is a new, additional tool to manipulate neurons and other cells in the body."

In optogenetics, researchers add light-sensitive channel proteins to neurons they wish to study. By shining a focused laser on the cells, they can selectively open these channels, either activating or silencing the target neurons. But using an optogenetics approach on cells deep in the brain is difficult: typically, researchers have to perform surgery to implant a fiber optic cable that can reach the cells. Plus, light is scattered by the brain and by other tissues in the body.

Never Be Heard: Nonreciprocal Acoustic Circulator Blocks Sound Waves From Travelling Back

By lookng at how an electronic circulator works, University of Texas at Austin researchers have adapted the concept and applied it to develop a non-reciprocal acoustic circulator. The device allows sound waves to travel one way and not travel back, basically a one-way road for sound. The circulator transmits these acoustic waves in one direction but block them in the other, in a linear and distortion-free way.

The device is similar in concept to a one way mirror. The acoustic circulator allows one to listen but not be heard.

Communications devices and radars use electronic circulators that manage transmission of microwaves and radio signals in three ports. These signals are transmitted in a sequential way from one port to the next. The unused port acts as an isolator to allow the signals to travel to the other port but not back.

Using this technology, the researchers adapted it to sound waves. This development can lead to advances in noise control, sonars and sound communication systems, and components for acoustic imaging and sensing.

The image is the non-reciprocal acoustic circulator as shown on the cover of Science. The device creates one way communication channels for sound letting sound in but not in the opposite direction. The arrows show the acoustic signals travelling through the device albeit in a non-reciprocal manner.

Brain Process In Encoding Sound Key In Study of Dyslexia

Northwestern University researchers found a systematic relationship between reading and how the brain encodes sound that may be key in understanding dyslexia.

Dyslexia is a disability where a person has difficulty processing letters and symbols. Also known as Developmental Reading Disorder (DRD), Dyslexia occurs when the part of the brain that helps process language does not recognize certain symbols or letters that is read by the person.

Dyslexia is not an eye or vision problem, it is an information processing problem. Normal thinking and cognitive functions are not affected and most people with dyslexia have normal intelligence, and many have above-average intelligence.

Disorders related to DRD are Developmental Writing Disorder (Orthographic Dyslexia) and Developmental Arithmetic Disorder (Dyscalculia). These conditions may appear alone or in any combination. All three involves the processing and interpretation of symbols and all three are considered a type of dyslexia. DRD is the most common and most associated with dyslexia.

There are four types of dyslexia:

• Phonological Dyslexia - Difficulty separating component parts of a sentence.
• Orthographic Dyslexia - Problem with writing such as spelling patterns
• Dyscalculia - Problem with basic sense of number and quantity
• Dysgraphia - Disorder which expresses itself primarily through writing or typing.

Using Thermoacoustics To Develop Self-Powered Nuclear Reactor Backup Sensors

A thermoacoustic device uses sound waves to move heat from one place to another or use heat to create sound waves. Using this principle, a thermoacoustic engine uses either the heat transfer or the sound waves to produce electricity, cooling, or heat pumping.


Currently, researchers are looking into electricity created from pressure (piezoelectricity), refrigeration, and cryogenic applications.


Another category thermoacoustics can be of use, is in the development of sensors, particularly backup sensors for nuclear reactors. The Fukushima nuclear disaster is a prime example of this.


In the Fukushima incident, the power connections failed cutting off electricity to the backups, pumps, and sensor systems shutting them down. The reactors overheated due to the high radioactive decay heat and the nuclear plant's operators could not monitor the fuel rods in the reactor and spent fuel in the storage ponds.

Motor Skills Interactions Affect How Brain Hemispheres Process Different Kinds of Sounds

The human auditory system is responsible for the processing of sound. It is the system used for the sense of hearing. As sound is picked up by the ear, it is relayed to the primary auditory cortex which is a region of the brain that process sound and helps us to hear.

The brain has two hemispheres, the left hemisphere and the right hemisphere, which are responsible for specific motor, cognitive, and organ functions. Researchers at Georgetown University Medical Center say that both hemispheres of the brain are responsible for specific processing of sound.

"Language is processed mainly in the left hemisphere, and some have suggested that this is because the left hemisphere specializes in analyzing very rapidly changing sounds," says the study's senior investigator, Peter E. Turkeltaub, M.D., Ph.D., a neurologist in the Center for Brain Plasticity and Recovery.