Posts Tagged ‘EEG’

by Amirah Al Idrus

When Nicolas Tremblay put three electroencephalogram (EEG) electrodes into a baseball cap, he was trying to build a tool to track focus in children with ADHD. He was pitching the device at a health hackathon last October when a nurse from the Montreal Heart Institute approached him with an idea: What if it could be modified for use in hospitals to diagnose patients with delirium?

Delirium—a sudden state of confusion characterized by reduced awareness of the sufferer’s environment—comes on suddenly and can last from hours to days. The American Delirium Society estimates the condition affects more than 7 million hospitalized Americans each year and, according to a Harvard Health report, delirium is the most common complication of hospitalization in people 65 and older.

Compared to hospitalized patients without delirium, those who suffer delirium tend to stay longer in the hospital and are more likely to develop dementia or other types of cognitive impairment and need long-term care after leaving hospital. Delirium is commonly detected via the Confusion Assessment Method, which helps health professionals identify problems with attention, memory, orientation and visual ability. Essentially, patients are asked a set of questions to assess their mental state. Though the method is standardized, it is not an objective test for the condition. What’s more, this approach doesn’t detect delirium early.

“Current methods are only able to detect delirium when the brain is already malfunctioning,” Tremblay said. “When delirium is detected at a later stage, it takes longer to bring the patient back. It costs a lot to the hospital because they have to keep the patient in hospital to revert delirium.”

NeuroServo set about creating a device to catch attention problems in hospitalized patients early, before these deficits manifest physically. Its educational tool, the electrode-fitted hat, measures electrical activity in the brain and signals attention—or lack thereof—via a built-in light that changes color. The device can also send EEG results via Bluetooth to a tablet app used by a teacher.

With input from doctors and nurses, NeuroServo developed a sterile version of the device, a disposable plastic strip holding three EEG electrodes that can be adhered to the patient’s forehead. It attaches to a portable EEG module that clips onto the patient’s jacket.

Using EEG to detect delirium isn’t a new concept; there is scientific proof that delirium can be found with EEG, Tremblay said. But using a traditional EEG on large numbers of patients just isn’t practical: The equipment is cumbersome, the process can require as many as 256 electrodes placed all over the scalp and a neurologist is needed to interpret the results.

NeuroServo’s device uses several algorithms specialized in a specific area of signal analysis, Tremblay said.

“The sum of these analyses is then used to return an easy-to-read graph and results to the nurse or caregiver,” he said.

As for the number of electrodes, NeuroServo’s electronics and algorithms are designed to obtain the best medical-grade EEG signal out of the forehead. ”This allows us to carefully track brain signals in the prefrontal cortex who is responsible for executive functions like attention control or cognitive flexibility,” Tremblay said.

He hopes to keep serving the educational market even as NeuroServo makes a push into the medtech sector. The company is still selling the cap for kids with ADHD, and the device is currently in a pilot study in France in children with autism spectrum disorder. As for its use as a delirium diagnostic tool, the Montreal Heart Institute is kicking off a pilot study this month. McGill University Health Centre will start a pilot later this year, and NeuroServo is working on a third study at a hospital in Boston.

What comes next depends on the outcome of those studies.

“We are waiting for the pilot results to be able to apply for approval from Health Canada, the FDA and so on,” Tremblay said.

NeuroServo is just one player working to make EEG possible for an area in which it has historically not been viable. Mountain View, California-based Ceribell came up with a portable device that quickly detects nonconvulsive seizures in ICU patients. Like NeuroServo’s device, Ceribell’s system doesn’t require a specialist to read its results—instead, it converts EEG signals into sound for a yes/no diagnosis within minutes.

https://www.fiercebiotech.com/biotech/neuroservo-s-portable-eeg-could-become-a-better-way-to-detect-delirium

Could a futuristic society of humans with the power to control their own biological functions ever become reality?

It’s not as out there as it sounds, now the technical foundations have been laid. Researchers have created a link between thoughts and cells, allowing people to switch on genes in mice using just their thoughts.

“We wanted to be able to use brainwaves to control genes. It’s the first time anyone has linked synthetic biology and the mind,” says Martin Fussenegger, a bioengineer at ETH Zurich in Basel, Switzerland, who led the team behind the work.

They hope to use the technology to help people who are “locked-in” – that is, fully conscious but unable to move or speak – to do things like self-administer pain medication. It might also be able to help people with epilepsy control their seizures.

In theory, the technology could be used for non-medical purposes, too. For example, we could give ourselves a hormone burst on demand, much like in the Culture – Iain M. Banks’s utopian society, where people are able to secrete hormones and other chemicals to change their mood.

Mouse meet man

Fussenegger’s team started by inserting a light-responsive gene into human kidney cells in a dish. The gene is activated, or expressed, when exposed to infrared light. The cells were engineered so that when the gene activated, it caused a cascade of chemical reactions leading to the expression of another gene – the one the team wanted to switch on.

Next, they put the cells into an implant about the size of a 10-pence piece or a US quarter, alongside an infrared LED that could be controlled wirelessly. The implant was inserted under the skin of a mouse. A semi-permeable membrane allowed vital nutrients from the animal’s blood supply to reach the cells inside.

With the mouse part of the experiment prepared, the team turned to the human volunteers. Eight people, wearing EEG devices that monitored their brainwaves, were taught how to conjure up different mental states that the device could recognise by their distinctive brain waves.

The volunteers were shown meditation techniques to produce a “relaxed” pattern of brainwaves, and played a computer game to produce patterns that reflected deep concentration. They also used a technique known as biofeedback, in which they learned by trial and error to control their thoughts to switch on a set of lights on a computer.

By linking the volunteer’s EEG device to the wireless LED implant in the mouse, they were able to switch on the LED using any of the three mental states. This activated the light-responsive gene in the kidney cells, which, in turn, led to the activation of the target gene. A human protein was produced that passed through the implant’s membrane and into the rodent’s bloodstream, where it could be detected. “We picked a protein that made an enzyme that was easy to identify in the mouse as a proof of concept, but essentially we think we could switch on any target gene we liked,” says Fussenegger.

Behaviour controlled

The possibilities this could open up extend as far as your imagination. For example, the implant cells could produce hormones, so how about giving yourself a burst of oxytocin before a stressful social event – just by concentrating on a computer game?

That’s possible in principle, Fussenegger says, but for now his team is focused on creating a device to help people who are locked-in, or those with chronic pain, medicate themselves. For people with epilepsy, a similar device could potentially pick up the specific electrical patterns that appear in the brain just before a seizure. It might be possible to engineer cells to react to this pattern and release drugs to lessen the seizure.

While the applications are futuristic, the work itself is very interesting, says Florian Wurm, head of cellular biotechnology at EPFL in Lausanne, Switzerland. He says it shows for the first time that you can link together two really important ideas – synthetic biology and mind control.

“But we have to consider the ethical and legal challenges associated with this kind of technology,” Wurm says. “The moment you can control genes by thought you might be able to interfere with human behaviour, perhaps against someone’s wishes.” He doesn’t want to paint a negative picture, though. “We shouldn’t close our eyes to these inventions. It’s not going to be made into a medical device any time soon but it’s interesting to consider who it could help.”

Fussenegger says he would like to start a clinical trial within 10 years.

Journal reference: Nature Communications, DOI: 10.1038/ncomms6392

http://www.newscientist.com/article/dn26538-human-thoughts-used-to-switch-on-genes.html