The next day I'm in the Lab with Schmiddi and Rolf. They are eager to tell me that I'm not the only person from Ireland joining the lab. Next week Matt Nicholson will also be joining.
"I think I know something about that," I explain, "Matt was being recruited before me and I think I came along as an afterthought."
They both smile.
Rolf speaks, "They say that Herr Nicolson knows plenty about Human to Computer interfacing. It's my specialism, so I will be keen to discuss some techniques with him."
I still haven't seen the Cyclone, which I'm told is part of the interface between the human brain and the computer world.
Hermann goes to a locked cupboard. He opens it and brings out what looks like a heavily wired cycling helmet.
"Hier. See if you can work out what is happening with it," he hands it to me and I take a look inside the helmet. I'd expected it to be smooth, but now I can see several bands of small spikes criss- crossing the inside section of the helmet. I work out they must be sensors.
"See how the Brain Computer Interface in this is on an altogether different scale from the systems trialled previously?" asks Hermann.
Rolf chips in, "Cyclone technology builds on decades of BCI research in academic labs, some of which is currently being tested in ongoing clinical studies. Levi Spillmann was a clever guy and this system uses many more electrodes than the systems used in previous studies. Earlier systems used laboratory equipment and personnel to be present. Cyclone's challenge is to build a safe and effective BCI that is wireless yet behaves like an implant. It must scale up the number of electrodes yet remove the need for external equipment (other than the device being controlled), and that users can take anywhere and operate by themselves."
"You sound like someone presenting a crazy wish list," I say.
"You won't believe how many times I've had to give The Talk," answers Rolf, smiling.
"There's been a few false starts, but now we can microfabricate the electrode threads out of thin film metals and polymers. We’ve developed new microfabrication processes and made advances in materials science to include the integration of corrosion-resistant adhesion layers to the threads and rough electrode materials that increase their effective surface area without increasing their size."
"But it is still the wrong side of the skull," I say.
"That's where we've produced the second breakthrough," explains Rolf. I see Hermann nod as well.
"You may have seen the material science descriptions of liquid metal microparticles that can be steered and reshaped by external magnetic fields? It's only just being published by ETH Zurich." Rolf looks excited.
I had to admit I'd never seen anything like the technology that I was now hearing about,
Hermann takes over, "By blasting collections of microparticles with magnetic fields at alternating currents, we can increase the microparticle temperature to 35 Celsius causing them to morph from a solid into a liquid state in just over a minute. It is the first time a material capable of both shifting shape and carrying heavy loads has been identified for use in microbots.
Rolf adds, "Because skin is a stratified squamous keratinising epithelium, it is impermeable. Otherwise we'd have a few problems! The clever thing is how microparticles emulate the layers of cells, which are routinely renewing and these particles migrate to the lower skin layers and on into the body. Its a phenomenon."
"Wow, isn't that defeating a major natural defence?" I ask, slightly worried that this science is becoming too god-like.
Hermann looks excited,"Exactly. Now these are such small particles and by emulating skin layers they find their way through the protection offered by the skin and other body defences. Do you see the possibilities? We can reconstitute the slivers to create terminators for some of the main neural pathways inside the brain and body. It is much less painful than drilling holes in the skull to implant electrodes.
"I see," I say, "It is allowing accessible and addressable connectors which can interface to human neural pathways?"
Hermann nods again, "Yes, we can in effect perform a brain implant from outside, using magnetic forces to guide the positioning of the necessary sensors. The shape-shifting material is the latest in a string of developments across the field of microbotics — as scientists look for potential medical and mechanical applications for tiny robots in everyday life.
"Recent microbotic innovations include microbots small enough to potentially crawl through human arteries, intelligent enough to be taught to swim, and others capable of flying through the air powered by tiny onboard power supplies."
Hermann adds, "In their liquid form, these microbots can be made to elongate, divide, and merge. In solid form, they can be steered at speeds exceeding 3 mph and carry heavy objects up to 30 times their own weight. The combination means a microrobot made from the sliver material could be deployed to fix electronics in difficult to reach places. The early design used neodymium iron boron which is toxic to humans. It would only be clinically safe for use inside humans if it were completely removed from the body afterwards. The newer designs are organically integrated. The human body cannot tell they are there, so it doesn't try to put up a fight.
“Our microbot still needs an external heater for melting and external magnetic field for controlling the movement and shape changing,” he said, "That use of an external force prevents the microbots from being able to 'run riot'. Without the external fields, they cannot do anything."
"Although if we have positioned them to the right nerve complexes, they still provide the valuable transitional gateway function," says Rolf.
"Does this mean that the neural processing can be conducted outside of the body?" I ask.
"Yes," says Rolf, "That is the beauty of the approach. As long as the receptors work and the signal can be detected, an outboard signal processor is entirely feasible. Look."
Rolf holds the Cyclone helmet up and I can now see several small circular fitments, each about the size of a wristwatch. He explains, "Those are receivers, which handle incoming signals from the brain. The same sensor can also transmit into the brain, sending it instructions. The link needs to convert the small electrical signals recorded by each electrode into real-time neural information. Since the neural signals in the brain are small (microvolts), the Brain/Computer link must have high-performance signal amplifiers and digitisers. Also, as the number of electrodes increases, these raw signals become too much information to upload with low power devices. Scaling our devices requires on-chip, real-time identification and characterisation of neural spikes.
Hermann looks at the helmet, "See how much of the system we have managed to put outside? Anything inside the head (or the rest of the body, come to that) needs to be protected from fluid and salts. Making a water-proof enclosure can be hard, and it’s even harder when that enclosure must be constructed from biocompatible materials.
"With the Cyclone we are allowing over 1,000 electrical channels to pass to external decoding and processing and that is in both directions. It is as complex as any microprocessor."
It's Day 2 for me at the Brant Lab and I'm blown away.
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