Just by thinking, humans may be able to control gene activity in a mouse.
People’s brain waves caused a gene to turn on in mice, researchers report November 11 in Nature Communications. The mind control trick isn’t telepathy. It’s a marriage of two technologies, one that uses bursts of light to turn on genes, and one that enables people to control external devices, such as computer cursors or robot arms, with their minds using “brain-computer interfaces.”
Such mixed technologies may one day head off epileptic seizures before they start.
“It’s conceptually interesting,” says Brendan Allison, a neuroscientist who works with brain-computer interfaces at the University of California, San Diego. But he and other neuroscientists say the study may be fatally flawed because it uses technology that cannot reliably distinguish one type of brain wave pattern from another. “This is certainly many years from human application,” Allison says.
For years Martin Fussenegger, a synthetic biologist at an ETH Zurich facility in Basel, and his colleagues have designed molecules that can tweak gene activity in response to light, a process called optogenetics. A certain wavelength of light activates light-sensing proteins. Those proteins then perform a job such as turning on or off gene activity or causing nerve cells to send electrical signals to other cells. Scientists have used such methods to tinker with mice’s memories (SN: 10/4/14, p. 6).Fussenegger got the bright idea to use brain waves to control a light bulb, which would then switch on a gene in a mouse. He and his colleagues engineered cells to contain a gene that would turn on in response to infrared light. The gene encodes the information needed to make a protein called secreted alkaline phosphatase, which has no biological activity in mice but can be measured in their blood. Cells containing the infrared-activated gene were sealed into a tiny capsule that the researchers could implant under a mouse’s skin. Along with the capsule, researchers implanted a near-infrared light-emitting diode, or LED.
Volunteers in the study wore a headset to measure electrical activity with an electroencephalograph, or EEG. Researchers asked the volunteers to relax, concentrate or do an exercise in which they learned to control their own brain waves.
“It was hard for most subjects to relax on demand,” says Fussenegger. The researchers had the subjects do deep breathing exercises and think about pleasant things. To induce concentration, the researchers had the volunteers play the computer game Minesweeper.
Information from the EEG headset then transferred wirelessly to a control device, which would flip on the LED when volunteers reached the desired brain state. The light then turned on production of alkaline phosphatase.
Fussenegger hopes to create a device that could detect brain waves presaging a seizure in people with epilepsy and trigger cells to pump out seizure-stopping proteins.
The problem for studying brain control in this case is that the technology was inadequate for the task, other scientists say. It is notoriously hard to identify brain states, such as relaxation, even with multiple indicators, let alone with a single brain wave measurement. “It’s very unlikely that the [brain-computer interface] outputs accurately reflected the subjects’ mental states,” says Allison.
The brain wave signals in the study don’t look like true EEG signals and could even have been produced by eye blinks, says José Contreras-Vidal, a biomedical engineer at the University of Houston. “I’m not convinced that’s what they say it is.”
Still, Allison says that collaboration with researchers who are well versed in brain control might produce a viable system that could eventually help people with a wide variety of neurological and psychiatric disorders.
Editor’s note: This story was updated on November 19, 2014, to correct the name of the game that volunteers played. Participants played Minesweeper, not Minecraft.