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Can a Mind-Reading Computer Speak for Those Who Cannot?

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Credit: Adapted from Nima Mesgarani, Columbia University’s Zuckerman Institute, New York

Computers have learned to do some amazing things, from beating the world’s ranking chess masters to providing the equivalent of feeling in prosthetic limbs. Now, as heard in this brief audio clip counting from zero to nine, an NIH-supported team has combined innovative speech synthesis technology and artificial intelligence to teach a computer to read a person’s thoughts and translate them into intelligible speech.

Turning brain waves into speech isn’t just fascinating science. It might also prove life changing for people who have lost the ability to speak from conditions such as amyotrophic lateral sclerosis (ALS) or a debilitating stroke.

When people speak or even think about talking, their brains fire off distinctive, but previously poorly decoded, patterns of neural activity. Nima Mesgarani and his team at Columbia University’s Zuckerman Institute, New York, wanted to learn how to decode this neural activity.

Mesgarani and his team started out with a vocoder, a voice synthesizer that produces sounds based on an analysis of speech. It’s the very same technology used by Amazon’s Alexa, Apple’s Siri, or other similar devices to listen and respond appropriately to everyday commands.

As reported in Scientific Reports, the first task was to train a vocoder to produce synthesized sounds in response to brain waves instead of speech [1]. To do it, Mesgarani teamed up with neurosurgeon Ashesh Mehta, Hofstra Northwell School of Medicine, Manhasset, NY, who frequently performs brain mapping in people with epilepsy to pinpoint the sources of seizures before performing surgery to remove them.

In five patients already undergoing brain mapping, the researchers monitored activity in the auditory cortex, where the brain processes sound. The patients listened to recordings of short stories read by four speakers. In the first test, eight different sentences were repeated multiple times. In the next test, participants heard four new speakers repeat numbers from zero to nine.

From these exercises, the researchers reconstructed the words that people heard from their brain activity alone. Then the researchers tried various methods to reproduce intelligible speech from the recorded brain activity. They found it worked best to combine the vocoder technology with a form of computer artificial intelligence known as deep learning.

Deep learning is inspired by how our own brain’s neural networks process information, learning to focus on some details but not others. In deep learning, computers look for patterns in data. As they begin to “see” complex relationships, some connections in the network are strengthened while others are weakened.

In this case, the researchers used the deep learning networks to interpret the sounds produced by the vocoder in response to the brain activity patterns. When the vocoder-produced sounds were processed and “cleaned up” by those neural networks, it made the reconstructed sounds easier for a listener to understand as recognizable words, though this first attempt still sounds pretty robotic.

The researchers will continue testing their system with more complicated words and sentences. They also want to run the same tests on brain activity, comparing what happens when a person speaks or just imagines speaking. They ultimately envision an implant, similar to those already worn by some patients with epilepsy, that will translate a person’s thoughts into spoken words. That might open up all sorts of awkward moments if some of those thoughts weren’t intended for transmission!

Along with recently highlighted new ways to catch irregular heartbeats and cervical cancers, it’s yet another remarkable example of the many ways in which computers and artificial intelligence promise to transform the future of medicine.

Reference:

[1] Towards reconstructing intelligible speech from the human auditory cortex. Akbari H, Khalighinejad B, Herrero JL, Mehta AD, Mesgarani N. Sci Rep. 2019 Jan 29;9(1):874.

Links:

Advances in Neuroprosthetic Learning and Control. Carmena JM. PLoS Biol. 2013;11(5):e1001561.

Nima Mesgarani (Columbia University, New York)

NIH Support: National Institute on Deafness and Other Communication Disorders; National Institute of Mental Health


Skin Cells Can Be Reprogrammed In Vivo

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Daniel Gallego-Perez
Credit: The Ohio State University College of Medicine, Columbus

Thousands of Americans are rushed to the hospital each day with traumatic injuries. Daniel Gallego-Perez hopes that small chips similar to the one that he’s touching with a metal stylus in this photo will one day be a part of their recovery process.

The chip, about one square centimeter in size, includes an array of tiny channels with the potential to regenerate damaged tissue in people. Gallego-Perez, a researcher at The Ohio State University Colleges of Medicine and Engineering, Columbus, has received a 2018 NIH Director’s New Innovator Award to develop the chip to reprogram skin and other cells to become other types of tissue needed for healing. The reprogrammed cells then could regenerate and restore injured neural or vascular tissue right where it’s needed.

Gallego-Perez and his Ohio State colleagues wondered if it was possible to engineer a device placed on the skin that’s capable of delivering reprogramming factors directly into cells, eliminating the need for the viral delivery vectors now used in such work. While such a goal might sound futuristic, Gallego-Perez and colleagues offered proof-of-principle last year in Nature Nanotechnology that such a chip can reprogram skin cells in mice. [1]

Here’s how it works: First, the chip’s channels are loaded with specific reprogramming factors, including DNA or proteins, and then the chip is placed on the skin. A small electrical current zaps the chip’s channels, driving reprogramming factors through cell membranes and into cells. The process, called tissue nanotransfection (TNT), is finished in milliseconds.

To see if the chips could help heal injuries, researchers used them to reprogram skin cells into vascular cells in mice. Not only did the technology regenerate blood vessels and restore blood flow to injured legs, the animals regained use of those limbs within two weeks of treatment.

The researchers then went on to show that they could use the chips to reprogram mouse skin cells into neural tissue. When proteins secreted by those reprogrammed skin cells were injected into mice with brain injuries, it helped them recover.

In the newly funded work, Gallego-Perez wants to take the approach one step further. His team will use the chip to reprogram harder-to-reach tissues within the body, including peripheral nerves and the brain. The hope is that the device will reprogram cells surrounding an injury, even including scar tissue, and “repurpose” them to encourage nerve repair and regeneration. Such an approach may help people who’ve suffered a stroke or traumatic nerve injury.

If all goes well, this TNT method could one day fill an important niche in emergency medicine. Gallego-Perez’s work is also a fine example of just one of the many amazing ideas now being pursued in the emerging field of regenerative medicine.

Reference:

[1] Topical tissue nano-transfection mediates non-viral stroma reprogramming and rescue. Gallego-Perez D, Pal D, Ghatak S, Malkoc V, Higuita-Castro N, Gnyawali S, Chang L, Liao WC, Shi J, Sinha M, Singh K, Steen E, Sunyecz A, Stewart R, Moore J, Ziebro T, Northcutt RG, Homsy M, Bertani P, Lu W, Roy S, Khanna S, Rink C, Sundaresan VB, Otero JJ, Lee LJ, Sen CK. Nat Nanotechnol. 2017 Oct;12(10):974-979.

Links:

Stroke Information (National Institute of Neurological Disorders and Stroke/NIH)

Burns and Traumatic Injury (NIH)

Peripheral Neuropathy (National Institute of Neurological Disorders and Stroke/NIH)

Video: Breakthrough Device Heals Organs with a Single Touch (YouTube)

Gallego-Perez Lab (The Ohio State University College of Medicine, Columbus)

Gallego-Perez Project Information (NIH RePORTER)

NIH Support: Common Fund; National Institute of Neurological Disorders and Stroke


An Aspirin a Day for Older People Doesn’t Prolong Healthy Lifespan

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Hands holding a pill and a glass of water

Credit: iStock/thodonal

Many older people who’ve survived a heart attack or stroke take low-dose aspirin every day to help prevent further cardiovascular problems [1]. There is compelling evidence that this works. But should perfectly healthy older folks follow suit?

Most of us would have guessed “yes”—but the answer appears to be “no” when you consider the latest scientific evidence.  Recently, a large, international study of older people without a history of cardiovascular disease found that those who took a low-dose aspirin daily over more than 4 years weren’t any healthier than those who didn’t. What’s more, there were some unexpected indications that low-dose aspirin might even boost the risk of death.


Wearable mHealth Device Detects Abnormal Heart Rhythms Earlier

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Zio patch

Caption: Woman wearing a Zio patch
Credit: Adapted from JAMA Network Summary Video

As many as 6 million Americans experience a common type of irregular heartbeat, called atrial fibrillation (AFib), that can greatly increase their risk of stroke and heart failure [1]. There are several things that can be done to lower that risk, but the problem is that a lot of folks have no clue that their heart’s rhythm is out of whack!

So, what can we do to detect AFib and get people into treatment before it’s too late? New results from an NIH-funded study lend additional support to the idea that one answer may lie in wearable health technology: a wireless electrocardiogram (EKG) patch that can be used to monitor a person’s heart rate at home.


Can Barbers Help Black Men Lower Their Blood Pressure?

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Barbershop trial

Caption: Barber Eric Muhammad (left) in his barbershop taking the blood pressure of patron.
Credit: Smidt Heart Institute, Cedars-Sinai Medical Center

You expect to have your blood pressure checked and treated when you visit the doctor’s office or urgent care clinic. But what about the barbershop? New research shows that besides delivering the customary shave and a haircut, barbers might be able to play a significant role in helping control high blood pressure.

High blood pressure, or hypertension, is a particularly serious health problem among non-Hispanic black men. So, in a study involving 52 black-owned barbershops in the Los Angeles area, barbers encouraged their regular, black male patrons, ages 35 to 79, to get their blood pressure checked at their shops [1]. Nearly 320 men turned out to have uncontrolled hypertension and enrolled in the study. In a randomized manner, barbers then encouraged these men to do one of two things: attend one-on-one barbershop meetings with pharmacists who could prescribe blood pressure medicines, or set up appointments with their own doctors and consider making lifestyle changes.

The result? More than 63 percent of the men who received medications prescribed by specially-trained pharmacists lowered their blood pressure to healthy levels within 6 months, compared to less than 12 percent of those who went to see their doctors. The findings serve as a reminder that helping people get healthier doesn’t always require technological advances. Sometimes it may just involve developing more effective ways of getting proven therapy to at-risk communities.


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