A brain implant that allows people with head injuries to function again proved so successful in a trial that participants refused to turn the device off.
The deep brain stimulation implant, developed by researchers at Stanford University, aims to boost activity between the regions responsible for consciousness learning, memory, thinking and problem solving.
During early trials, five people with brain injuries reported they were able to concentrate, read, remember, drive properly and get through the day without napping.
The therapy proved so effective that researchers had trouble completing the final phase of the study, which was to switch off the device for three random participants – after two of the patients declined.
Gina Arata, a trial participant who suffered a brain injury following a car crash in 2001, said: “I couldn’t remember anything. My left foot dropped, so I’d trip over things all the time. I was always in car accidents. And I had no filter – I’d get p---ed off really easily.
“Since the implant I haven’t had any speeding tickets. I don’t trip anymore. I can remember how much money is in my bank account. I wasn’t able to read, but after the implant I bought a book. And I don’t have that quick temper.”
Researchers selected patients for the trial who had recovered from comas with brain systems believed to be still well preserved, but not functioning as well as previously.
“In these patients, those pathways are largely intact, but everything has been down-regulated,” said Dr Jaimie Henderson, professor of neurosurgery.
“It’s as if the lights had been dimmed and there just wasn’t enough electricity to turn them back up.”
The researchers hoped that precise electrical stimulation of specific areas could turn the “lights” back up, and created a virtual model of each participant’s brain so they could trial stimulation at different locations ahead of surgery.
Guided by these models, Dr Henderson implanted the devices in the five participants aged between 22 and 60 who had sustained injuries between three and 18 years earlier.
After allowing the device to bed-in for a fortnight, the participants spent 90 days with it turned on for 12 hours a day.
At the end of the 90-day treatment period, the participants had improved their mental processing speeds by an average of 32 per cent, researchers said.
The device allowed the patients to resume activities that had previously been impossible such as reading books, watching television series, playing video games or finishing homework assignments.
They also reported feeling less fatigued and could get through the day without napping.
When one participant was randomised to have their device turned off for three weeks, their mental processing speed dropped by 34 per cent.
“This is a pioneering moment,” said Dr Nicholas Schiff, a professor at Weill Cornell Medicine and co-senior author of the study.
“Our goal now is to try to take the systematic steps to make this a therapy. This is enough of a signal for us to make every effort.”
The research was published in the journal Nature Medicine.%n