Don't get me wrong, I think the custom computers that are referred to as "cyberdecks" are cool, and I've even built some myself, but I've always been irked by the use of that term to refer to machines that have a regular indirect human-computer interface in the form of a keyboard, screen, etc.
My first exposure to that word came from reading Gibson, and in Gibsons work there is a very clear line between "terminals" (regular computers) and "cyberdecks" and that is that a cyberdeck connects directly to the brain.
Maybe these custom computers should be called "cybredecks". I don't know the actual definition of "cybre", but my first exposure to the word (misspelling?) was in the fediverse and it was used in reference to things with the cyberpunk aesthetic.
So when I see a cool custom, often hand-made computer without a neural interface I involuntarily roll my eyes a little.
But what would it take to do it right? I know what you're thinking, you're thinking "well Jason, not everyone is going to drill a hole in their head or even attach electrodes to it like you did when you were 13 to try to control their computer with their mind...", but maybe they should.
There's been a fair amount of invasive work in this area since the mid-to-late 1900's but most of it involves surgery. That was a line I've never really crossed because honestly it's messy and complicated if you don't have access to the right tools, facilities and staff. It's also largely irreversible which is something I try to avoid. But since my early experiments I've learned a lot and I think there's some non-invasive ways to make such a thing, some of which I'm not sure have been tried yet.
A neural interface has an input and an output component like most any computer interface. To keep things straight I'm going to refer to I/O from the computer's perspective, input being the control signals sent to the computer from the person and output being the data sent form the computer to the person.
The input side has some well-established and easy answers. An EEG-type device uses electrodes attached to the skin to detect brainwaves that can be display and recorded (this is what I was experimenting with using my VIC-20 when I was 13). Various numbers of electrodes have been used but even just a few can produce a usable control signal as demonstrated by several games and children's toys. Most of the cost and complexity of the EEG hardware comes from the precision amplifiers needed to boost the weak signals, but all of that has become very common and inexpensive in the last decade or two. The rest of the work is in analyzing the signals but here again this is something that can now be done with commodity hardware and open-source algorithms.
The output side is where things get tricky. Traditionally feeding any sort of electrical signal *into* the brain involves surgically-implanted electrodes that stimulate the brain tissue directly. There have been sophisticated demonstrations of this, some recently but the work of literally "drawing images on the brain" goes much further back than any contemporary self-proclaimed genius wants you to know. This approach has potential but it's not something you should try at home.
However there is a non-invasive way to put a signal into the brain called transcranial magnetic stimulation (TMS). This technique uses a process similar to how an electric current can be induced in a wire without touching it using a magnetic field. A TMS device is capable of stimulating brain cells without direct contact with the brain, so this is the starting point of the output side of our cyberdeck interface.
*This is where we get into things that I don't know the research status of.*
The first thing that comes to mind is to use an array of TMS fields to "draw" on the brain similar to the invasive techniques, and perhaps something like beam-forming could be used to do this with some level of precision, but I have another idea that is both simpler and I think better.
Instead of attempting to simply paint an image on the brain what I propose is using TMS to stimulate a single point with precision in a reliable fashion. To transmit information into the brain, the information is serialized and then signaled into this single area in the same way that a single wire can be used to transmit data by encoding and decoding it on either end. This single point could use a digital or analog encoding (experimentation would be needed to determine which works best), and there is a wide-range of existing encoding techniques that could be explored.
In order for this to work the brain would need to be trained to decode a serial data stream. This might sound far-fetched but most of us do this all the time in the form of reading written language. *Writing is a very low-fidelity encoding of one person's thoughts into a stream of characters that is then deserialized and decoded by another persons brain.* If our brains are capable of learning to do this using a visual data channel, I don't see why they couldn't do the same using a TMS-induced signal which essentially creates a new sensory channel.
It would take training to learn how to use this new "sense", and it might take a long time (how long does it take an illiterate adult to learn to read?), but I don't see any reason to believe that it's impossible, and if it could be done, it would make a non-invasive direct neural interface not only possible, it could be produced inexpensively and used by virtually anyone.
Aside from being the right interface for a cyberdeck, such a device could also be the most accessible computer interface ever made, since it would allow working with a computer regardless of other sensory impairments.
There are of course risks involved in developing such a device even if it doesn't involve surgery and I would have to think about it more and do more research to devise a plan for conducting the experiments to develop it in as safe a way as possible. It's also possible that there's something I don't know about that would invalidate the approach altogether. But given the potential, I think it's worth throwing some brainpower at.
Plus, then I could submit a cyberdeck project to Hackaday without cringing.
Jason J. Gullickson, 2026