Pitt study probes 'covert consciousness'

Ricardo Iriart last saw his wife conscious four years ago. Every day since, he has visited Ángeles, often spending hours talking to her in hopes that she could hear him.

Over the last year, he's gotten a new understanding of his wife's condition, participating in cutting-edge research into "covert consciousness." It's an emerging field of study that probes what patients with disorders of consciousness can comprehend, even when they can't respond.

Earlier this year, the University of Pittsburgh became the first research institution in the U.S. to use an Austrian device called the mindBeagle in a clinical trial of covert consciousness.

"Even though they are not scoring to show that they are aware of their environment, the mindBeagle allows us to tap into whether they are internally following directions," said Katya Hill, a professor who recently moved from Pitt to chair the department of communication science and disorders at Gannon University. "In some cases, they are able to answer yes or no questions when we train them well enough with the paradigms on the mindBeagle."

Over the course of 17 sessions, Iriart took his wife from her skilled nursing facility in Cranberry to UPMC Mercy to be hooked up to electrodes and tested with the mindBeagle.

The couple met when they were freshmen in college in their native Argentina. Ángeles was an accounting major and the star of the local club field hockey team, while Ricardo studied business. As a married couple, they moved frequently for Ricardo's work, settling permanently in the United States 25 years ago.

As they moved, Ángeles found different jobs, often working with children, and effortlessly excelled in new sports. She won golf trophies in Colombia and Brazil. In Pittsburgh, she picked up tennis, becoming captain of the over-40 team at the Oxford Athletic Club in Pine.

It was there, during a match in September of 2021, that she collapsed on the court.

Her doubles partner was a doctor, but even with immediate medical help, Ángeles, then 61, never recovered. She had suffered a brain hemorrhage brought on by an arteriovenous malformation, or AVM, a tangled mass of blood vessels that had likely been present since birth without causing symptoms.

When Iriart saw his wife at the hospital about an hour after she collapsed, she couldn't speak but still seemed awake and conscious enough to recognize him and grab his hand. From there, however, she slipped into a coma after undergoing brain surgery to lessen the pressure from the hemorrhage.

About two months later, she opened her eyes, but never showed clinical signs of responsiveness.

"All the different people that we had seen, all the professionals, would say that there was nothing else to do and that she was unresponsive," said Iriart. "The prognosis was basically, there is no hope."

Even so, Iriart always asked the doctors at his wife's appointments if there were any new opportunities or treatments, or anything at all that could be done to help his wife.

A study to sniff out consciousness

About a year ago, he received a letter inviting him to participate in a clinical trial for the mindBeagle — so named because just as the beagle breed of dogs are used to find people using their sense of smell, the mindBeagle device attempts to sniff out consciousness.

Disorders of consciousness run along a spectrum — from a coma, where the patient's eyes remain closed, to unresponsive wakefulness syndrome (previously called a vegetative state), where there is a sleep-wake cycle but patients do not respond to stimuli, to a minimally conscious state, where there are small signs of awareness. There is also a different condition called "locked-in" syndrome where patients are fully conscious but unable to move or speak.

Over the last decade or so, scientists have started to use neuroimaging to detect consciousness in those unable to show signs at the bedside. Studies have shown that 10% to 20% of patients who show no awareness during behavioral examinations do have evidence of conscious awareness through neuroimaging such as MRIs or EEGs.

The mindBeagle uses EEGs combined with up to seven vibrating rods placed around the body. Participants are initially told to pay attention to, for example, only the rod vibrating on the right wrist.

When the sensation hits that they are looking for, they should register a particular type of brain wave called a P300 — the same feeling that is generated when a grocery store shopper sees an item on the shelf that they are looking for.

If patients are able to perform statistically better than chance in following commands to recognize the vibrations, the device can move on asking yes or no questions. For example, it might ask a patient "Is fire hot?" or "Did you play basketball in high school?" and to focus on vibrations in their right wrist for yes or their left wrist for no.

Pitt tested the mindBeagle on 12 patients as part of the clinical trial, funded by the Beckwith Institute and UPMC Rehabilitation Institute. Each patient required their own protocol, said Amber Lieto, a Pitt Ph.D. student in speech and language pathology who conducted much of the research.

For Ángeles Iriart, for example, Lieto tried giving her instructions both in English and in her native Argentinian Spanish. She also involved Ricardo in the trial under the assumption that his wife might respond better to a familiar voice.

"When I saw the results I was getting from engaging directly with a family member, it spoke for itself," said Lieto. "I could just see the interactions were meaningful to not only the participant but the caregiver."

And while Ángeles's performance was up and down, it was clear that she did seem to understand some commands. Her accuracy recognizing when the rods vibrated on the correct wrist reached as high as 77%, said Ricardo, and she was also able to do better than chance answering some yes or no questions.

In fact, every single participant in the study was able to perform above chance on at least one aspect tested by the mindBeagle.

"We remain very excited with our first pass with this small group of cases that what we're seeing is meaningful," said Amy Wagner, a Pitt professor and director of the Brain Injury Medicine Fellowship.

Each patient had a different medical history and some patients saw more consistent results than others. One patient was correctly able to answer yes or no to questions such as his wife's name, his house color and his favorite basketball team. Many, including Ángeles, saw improvement on a coma scale rating their level of consciousness, and at least one patient emerged from a coma after the clinical trial.

"It gave the families some hope, especially ones that felt that there was something going on but there was no evidence of that," said Hill. "It was very emotional and positive because at least they felt they were trying something — no matter the results, it wasn't like they were disappointed."

Seeing the potential

While the mindBeagle is still in a testing stage, there is incredible potential for devices that allow communication from patients with disorders of consciousness, said Wagner, including the ability for patients to make decisions about their own care.

After Ricardo Iriart finished the Pitt study with Ángeles, he received an opportunity to participate in another study at Carnegie Mellon University, which uses different technology to probe covert consciousness. Although the results are preliminary, they are encouraging.

He has always thought that she reacted to the presence of familiar voices and people, such as when he holds up a phone to let her sisters talk to her from Argentina, but now feels more confident.

"At the beginning, the clinical diagnosis was that she was unresponsive. That was not really the case," he said. "Now I am under a different assumption, which is that she is listening and she is understanding."

The day of her collapse, Ángeles had worked late the night before, until 10 p.m. at the Holy Family Institute in Emsworth, and was asleep when Ricardo left for work that morning.

He gave her a kiss and whispered, "I love you," and she responded, "I love you too" back to him. "I think it was the most beautiful, everyday scene that I could have as a memory before her injury," said Ricardo. "I always repeat those words to her in the hope that one day she will answer me."

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