Uploading Your Mind Does Not Compute

BY PETER KASSAN

THE NOTION OF UPLOADING YOUR MIND TO a computer has been trending lately, from movies like Transcendence to websites of neurophysiologists and computer scientists (Google “uploading the brain” for many websites and videos). The only thing you can actually upload to a computer is, well, a computer file—something that’s designed to be uploaded—something in machine-readable format, such as a photograph in JPEG format or a music track in MPEG format or a text file in ASCII format. The mind isn’t a computer file, so the idea of uploading your mind must refer to a different idea.

In the good old days of artificial intelligence, some people thought we could discover (or maybe invent) a “language of thought,” something that looked like a natural language (such as English), but one that could be manipulated by computers in the same the way computers manipulate statements in so-called computer languages (although statements in a computer language are actually more like instructions in a recipe). At first, attempts were made to use classic symbolic logic (“A implies B and B implies C, so A implies C.”). These attempts failed because people don’t use words in the same way symbols are used in symbolic logic. So the researchers invented something they called “non-monotonic” logic, which didn’t work very well, either. These notions have been largely if not completely abandoned.

Even if there really were a language of thought in which your mind’s contents were recorded, there would still be the problem of downloading it from your brain before we could upload it anywhere. Unfortunately (or maybe fortunately), there’s no computer interface to your mind—no USB port, or that thing at the base of your skull in The Matrix. Since there’s no interface to your mind, the notion of uploading it actually imagines something else—uploading your brain to a computer. Since we know that your brain produces your mind somehow, if we just copy your brain that should do the trick.

At first, the notion may seem plausible. After all, the brain is a computer, isn’t it? Well, no, the brain isn’t actually a computer—even though the metaphor is compelling—so there’s no guarantee that a computer can do whatever your brain does. And since your brain isn’t a computer file any more than your mind is, we can’t actually upload it, either. So the notion of uploading your brain must really be a two-step process:

(1) Record your brain.

(2) Upload that information into a computer program that simulates your brain.

Recording Your Brain

The human brain is often said to contain 100 billion neurons (nerve cells), the cells that do the main work. Recently, neuroscientists have computed a slightly lower estimate of about 85 billion. Both are large figures, and the fact that such numbers are round tells us that they’re estimates. But to model your brain accurately we would need to know exactly how many neurons you’ve got, and record detailed information about each one. The problem is compounded by the fact that neurons are extremely variable. As most of us remember from high school or college biology or psychology, the typical neuron consists of a soma (the cell body), an axon (the main conduit for signals to other neurons), and a large number of branching dendrites (where signals from other neurons are received). Typically, the signal from one neuron to the next is transmitted over a tiny gap known as a synapse. However, some neurons lack an axon, some lack dendrites, and some communicate from axon to axon rather than axon to dendrite. Further, some neurons communicate by neurotransmitters, some by electrical connection, and some with both. In some neurons, signals proceed not only from axon to dendrite but also back. And, of course, many neurons receive signals not from other neurons but from sense organs such as the eyes, ears, nose, skin, as well as sensations such as hunger and thirst, pleasure and pain. And many neurons transmit signals not to other neurons but to voluntary and involuntary muscles or to glands.