The science fiction of melding man and machine has played out for decades onscreen, from The Six Million Dollar Man to The Terminator.
But the bionic hybrid age may well be flickering to life - real life - in the Calgary lab where scientists who made history fusing snail brain cells to a computer microchip six years ago are poised to try the same feat with human cells.
Researchers at the University of Calgary's Hotchkiss Brain Institute are to announce Tuesday that they have made a key advance in connecting brain cells to a newly designed silicon chip, crafted with the National Research Council of Canada, that allows them to "hear" the conversation between living tissue and an electronic device as never before.
"It used to be like seeing two people talking at a distance. ... You didn't know what they were saying or even what language they were speaking. But now it's like putting a microphone beside them," said Professor Naweed Syed, head of the university's department of cell biology and anatomy, who has led the work on the so-called neurochip.
Published online this week in the journal Biomedical Microdevices, the latest Calgary work makes it immediately possible to use a neurochip to screen drugs for patients with brain disorders and determine which ones are likely to work based on what the brain cells "say."
Dr. Syed said his team plans to run the first drug-screening experiment within the next few months on brain tissue taken from a patient undergoing surgery for epilepsy.
Being able to monitor the dialogue between cell and silicon chip is a crucial step toward one day manipulating it, raising the possibility of neurochip implants that can operate artificial limbs, help restore sight or language after a stroke, or repair neurons that malfunction in a wide range of brain disorders, from Parkinson's disease to Alzheimer's.
The work also hints of a future in which living neurons could help drive silicon circuits in a central processing unit, becoming part of what some observers have dubbed "an organic computer."
Molly Shoichet, a biomedical scientist at the University of Toronto who holds the Canada research chair in tissue engineering, described a "growing momentum" in the bio-engineering field as collaboration increases between engineers, biologists, and surgeon scientists.
In this case, Dr. Shoichet said the Calgary researchers "have made a strong case for what they achieved," recording the activity of neurons. But she cautioned that the new paper involved only a small sample size of neurochip recordings, and these, she noted, were not based on mammalian brain cells, but mollusc neurons.
"The advance made is in the design of a simpler tool - that is the creation of a microchip [to facilitate]analysis," she said.
Until now, the Calgary group had conducted most of its research on cells taken from rat and snail brains. Snail neurons, Dr. Syed explained, are four to 10 times the size of human brain cells and easier to manipulate on a chip one millimetre square.
While the size of the chip has not changed, he said the new design will allow researchers to monitor brain-cell activity in powerful detail over several days.
Brain cells talk to each other in a language of electrical and chemical signals that prompt each neuron to either fire up or relax. Chemical signals pass between an array of nerve fibres, known as synaptic connections, that look much like tree branches under a microscope. Electrical signals pass through gateways on the cell surface called ion channels.
The group developed a special recording device that is embedded beneath the surface of the microchip, which in turn connects to a patch clamp that can amplify all the activity taking place between the brain cells on the chip's surface.
"We can track subtle changes in brain activity at the level of ion channels and synaptic potentials, which are the most suitable target sites for drug development," Dr. Syed said.
As it stands, most drug screening is a cumbersome process involving cells on a Petri dish that can be measured only one or two cells at a time. The chip method allows researchers to record whole networks of cells at once.
The new neurochips have also been fully automated so that any researcher - without months of training - can marry cells, from the heart, or smooth muscle, to the microchip and easily gauge their reaction to various medications, Dr. Syed said.
But the chip doesn't come cheap, he admitted, estimating that for now the cost would run at $30,000 for 750 reusable chips.
The 53-year-old Dr. Syed, who grew up watching The Six Million Dollar Man, said he sees the neurochip as an evolving work that will eventually stand as an implantable device that could direct brain cells to either fire up or say, "Hey, guys, calm down."
He described watching a recent football game between the Calgary Stampeders and the Saskatchewan Roughriders along with some 30,000 other people when he received a cellphone call. It struck him that it was a unique frequency that had allowed the caller to reach him specifically out of the massive crowd. He envisions, one day, a microchip that can also be "dialled up by a special frequency" and transmit electrical messages to other parts of the brain to block pain, say, or addiction cravings.
"That's what the dream really is all about ... where a man-made device can be integrated into living human tissue and become part of it," Dr. Syed said.
The humbling part, he said, has been the complex wiring of the human brain.
Several international groups have similar dreams. Since the 2004 breakthrough, a European team has fused mammalian cells to a silicon interface, and perhaps most memorably, U.S. researchers unveiled monkeys that could feed themselves peanuts by operating a robotic arm with mind control.
"A lot of people still think bionics is science fiction," Dr. Syed said. "It's not. It's already here."