I protest.

We can remember that for you wholesale.

Slashdot mentions a Guardian story that is based on a New Scientist story (phew!) about the world's first brain prosthesis. The hippocampus is, among other things, the part of the brain that allows short term memories to become long term memories. People with damage to the hippocampus, say by a stroke, can no longer form long-term memories. Well, a team lead by Dr. Theodore Berger at USC has developed a "silicon hippocampus." According to the New Scientist article, they devised a mathematical model of how the hippocampus works, designed a chip from that model and will now connect the chip to a living rat brain, in vitro at first and then later in vivo. Read the article, it is fascinating.

This is, um, mindblowing. I have experienced the state of losing the ability to form long term memories, certain anaesthetics (the so-called "amnesiacs") work this way. A couple of years ago I had an endoscopy in which I was given such a drug. The interesting bit is that I remember the first few seconds of the procedure and then, with no gap, I am being wheeled to the recovery room. I am awake and alert and am speaking. I don't remember what I was saying when I became aware, but the first thing I do remember saying is, "that was fast!" This might be something like the experience of someone with hippocampal damage who received this prosthesis. Only theirs would be much, much more intense and profound.

This is a big step, as well, toward being able to make other neural repairs. What if we could provide prostheses for other parts of the brain, so as to help stroke or accident victims? This then raises the question of identity. If part of the thing I think with, the thing that is me in the most basic, intimate sense, is silicon, what am I? Perhaps we will have to adjust our concept of "identity," not to mention that of what it is to be human. Very challenging questions, but also very useful ones. These questions may become truly meaningful in a concrete (rather than philosophical) sense for the first time.

(Bonus points for the person who knows where I got the title of this entry.)