Ultrasound to Modify Neuron Firing

I've mentioned in the past about scientists potentially using ultrasound to manipulate brain functioning. Now it appears that scientists have published a new paper indicating their findings of using low frequency ultrasound pulses to modify brain activity.

Newswise — In a twist on nontraditional uses of ultrasound, a group of neuroscientists at Arizona State University has developed pulsed ultrasound techniques that can remotely stimulate brain circuit activity. Their findings, published in the Oct. 29 issue of the journal Public Library of Science (PLoS) One, provide insights into how low-power ultrasound can be harnessed for the noninvasive neurostimulation of brain circuits and offers the potential for new treatments of brain disorders and disease.

Basically this is similar in principle to transcranial magnetic stimulation but uses ultrasound in place of electromagnetism. It can be used as a way of non-invasively stimulating the brain in much the same way as TMS is used. I think the potential benefits of this method include a much greater targeting accuracy than TMS. TMS can only stimulate a relatively large region of the brain, but ultrasound has the potential to be much more selective. The article mentions the possibilities of this new technology.

When asked about the potential of using his groups’ methods to remotely control brain activity, Tyler says: “One might be able to envision potential applications ranging from medical interventions to use in video gaming or the creation of artificial memories along the lines of Arnold Schwarzenegger’s character in ‘Total Recall.’ Imagine taking a vacation without actually going anywhere?”

I'm not quite sure how accurate this method of targeting would be and this seems like a bit of fanciful speculation thus far. It sounds, though, that this could lead to something akin to a virtual reality device that beams sensory experiences directly into a person's head. Sony has already patented something to this effect in the past.

The technique suggested in the patent is entirely non-invasive. It describes a device that fires pulses of ultrasound at the head to modify firing patterns in targeted parts of the brain, creating "sensory experiences" ranging from moving images to tastes and sounds. This could give blind or deaf people the chance to see or hear, the patent claims.

At the very least, this new technology will allow researchers to gain new insights into the workings of the brain. It could be used like TMS to selectively activate/deactivate brain regions to decipher their functioning. It may also have utility for a variety of brain disorders. I think it may be able to reach almost any brain region.

TMS has a focal accuracy greater than 1 cm. According to this patent, ultrasound could increase the focal accuracy of brain stimulation down to 1 mm. So this shows that there is a trend towards more accurate non-invasive targeting of brain areas. Would it be possible to have an even greater focal accuracy than 1 mm? I think the ultimate goal of brain stimulation would be to have the capability of non-invasively stimulating individual neurons inside the brain. I suspect that this may eventually be possible with more refined control of physics. I wouldn't rule out this distinct possiblity and see that the science is progressing in this direction. Though, I think it is merely speculative currently.