Reality Check: Brain-Computer Interfaces

From Neuromancer, to The Matrix and most recently Surrogates, Dollhouse and Avatar, brain-computer interfaces (BCI) have always been popular in science fiction. Frequently the depiction of this technology have a tendency to put a greater emphasis on “fiction” than on “science” by perpetuating the fundamentally flawed metaphor of the human brain as a hardware and software composite.

Unfortunately, the human brain is the farthest thing from a von-neumann computer (a.k.a. a stored-program computer) we could possibly imagine. Natural processes lead to the emergence of neuronal topology that then give rise to complex human behavior. Your mind is not your brain’s software – because in reality there is no software at all – information flows through the brain and computation happens naturally due to the physical properties of the neuronal pathways.

The key concept I want you to embrace is that your mind is fully described by the physical configuration of your brain. To “edit” your mind – for example, to implant a memory or instantly learn a skill – it would be necessary to either physically rewire your neurons or have your brain significantly augmented to support on-demand topology modification.

Input/Output interfaces are the most feasible in the short term

Right now we are only able to communicate with the brain by stimulating neurons (input) and measuring specific properties of neurons (output). There a lot of incredible things we can do using this approach, the key concept is to think in terms of what could be done using real-time input and output streams:

  • Give people senses they don’t have (vision to the blind, GPS to the willing);
  • Give people actuators they don’t have (arms to amputees, drive a car with your mind);
  • Read active thoughts and intentions, including memories a person is actively conjuring;
  • Give people artificial experiences using multi-sensorial stimulation;
  • External knowledge databases (Google in your head);
  • Ultimately, we could have an isolated brain with full-digital I/O, enabling for example, full-prosthetic bodies and disembodied living;

I/O interfaces in science-fiction:

  • The Matrix: the Matrix simulated world;
  • Ghost in the Shell: full-prosthetic bodies, “the net”, external memories;
  • Avatar and Surrogates: remote control of a prosthetic body;

Read/Write interfaces are possible but they will probably require advanced brain augmentation

There are things however, we might never be able to do using I/O interfaces because they require being able to read and modify the brain’s neuronal topology directly (read/write):

  • Read a memory, without the subject actively conjuring it;
  • Write a memory without generating an experience (“imprinting”);
  • Significantly faster-than-real-time learning or instant knowledge transfer;
  • “Editing” personality traits;

We currently lack significant understanding of how to address the challenge of building such R/W interface to the brain. First we would need significant advancements in neuroscience in order to learn how to design useful neuronal pathways. Secondly, we will need a few fundamental breakthroughs in nanofabrication and nanorobotics to gain the ability to manipulate matter with the degree of accuracy needed to make useful (and desirable) changes to a living human brain.

R/W interfaces in science-fiction:

  • The Matrix: instant learning through downloads;
  • Ghost in the Shell: hacked memories, “puppet” agents;
  • Dollhouse: personality imprints, “tabula rasa” programming;

Talking to the brain and altering the brain are two fundamentally different tasks

Although limited, I/O interfaces are the easiest to build. Even though every bit of information that enters the brain indirectly leads to neuronal topology change, the minutia and scope of these changes are not under our direct control. This means that there are fundamental limits of what we can do with I/O interfaces alone.

However, I/O brain-computer interfaces will significantly expand our mental landscape in the near term by adding new information streams to our conscious experience of the world. Yet, the dream of instant learning and mental imprints might never be achieved before we move on to considerably enhanced or artificial brains that provide easy R/W access to neuronal topology.

In other words, for the foreseeable future, you will not be downloading a kung-fu app into your brain. And when you are finally able to do so, you might not have what you currently call a brain anymore.


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  2. Collin Bockman   •  

    Great post Rod. The thing about I/O, though, is that output is typically much easier than input. We see this with modern robotic prostheses. Getting a person’s nervous system to move a robotic arm around is easier to do than getting the person’s brain to recognize where the arm is located in space and whether it is touching anything, is hot or cold, etc. I think we will have reliable output devices–things like the “interceptors” in Ghost in the Shell, devices that tell whether a person is recalling or fabricating a “memory,” etc–well before we have reliable input devices. Indeed we already have lots of pretty good output devices while inputs like bionic eyes are coming along more slowly and inputs to non-sensory functions such as language are basically still on the drawing board.

    Not that this is a terrible situation, I think we can get a tremendous amount of usefulness from output devices alone, especially output devices that let us study brain data in real-time. I’m currently obsessed with the research being done on monks who have practiced many thousands of hours of meditation and how their brains are different. Also think output combined with feedback through a traditional computer screen might enable an entirely new method of learning things and, if capable of outputting what a person is imagining in her “mind’s eye,” a way of helping people learn how to visualize things better. Anxiously waiting for my ACME home brain scanning device.

  3. Dr. Yitzhack Schwartz, MD   •  

    Nice (!) up-to-date post Rod, but… even judging by the number of patent filings dealing specifically with BCI it seems that the hype in the media is much bigger than the true hope. The numbers of relevant published US patent applications were merely 23, 11 and 13 for 2009, 2008 and 2007, respectively. This represents mostly technological imaturity. One may claim that most researchers nowadays believe in open sharing and don’t even bother filing for patents. I still think the numbers are so low because nothing much is actually happening and the significant breakthroughs we are all awaiting are yet to come. As the comercial impact is going to be huge I’m certain companies as well as universities will protect the IP by all means and thus IP is a good indicator. BTW, are you aware of a serious (evidence-based) forecast that aims to project when we’ll truly be utilizing BCI in big numbers? I’m not referring to the rather ‘low-hanging-fruits’ but to more complex applications that would revolutionize our lives. I tend to agree they will arrive but later than most ‘futurists’ predict.

  4. Mike   •  

    Nice post. I think we will have a connectome (wiring diagram) of the human brain within 4-7 years. Once we have that, it will become easier to construct better brain computer interfaces. A BCI could communicate with brain cells using optogenetics or perhaps ultrasonic neuromodulation. Modifying consciousness with neurotechnology should be awesome as well (Paradise engineering). I did a post about BCI’s and the wireless neurosociety a while back on my own blog that covers related material.

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