What if a stranger could see into your mind?
“A penny for your thoughts,” my mother used to say when I was brooding. As I got on into my teen years, she was less and less likely to get her money’s worth, and–even corrected for inflation and then some–I would probably have gotten even less out of my own kids.
But suppose parents didn’t have to offer even a penny’s worth of bribes? Suppose they could switch on some new technological marvel and know their kids’ thoughts?
Or, say you’re an attractive young woman being interviewed by a male partner in a law firm. Suppose you could surreptitiously scan his brain during the conversation and get the readout of his thoughts on your cell phone minutes later?
Or, you’re a young man on the make in a crowded bar; don’t you want to know which of the three or four women you’re eyeing is most likely to take you home?
These science-fiction scenarios have just come a bit closer with a new study from the University of California at Berkeley. Using MRI—magnetic resonance imaging—a group spanning programs in psychology, neuroscience, and physics has gotten the most impressive results so far in the new science of mind-reading.
That’s right—science. One branch of brain imaging now deals with figuring out what people are looking at by scanning their brains. And this neurological guessing game is only a prelude; ultimately, imagers will be looking not just at brain activity tied to visual patterns but at thoughts, motives, and feelings.
Here’s what they did. First, two human subjects were each shown 1,750 natural images, while the visual area of their cerebral cortex was scanned. Wave forms were plotted to reflect activity at the level of small mapping units called voxels. Then the researchers selected 120 ofthe pictures for their guessing game. This time only the subjects knew what they were looking at, while the scientists looked only at the record of what went on in the brain.
For one subject, they guessed right on 110 out of the 120 pictures. I would call this astounding. For the second subject they were right for 86 of the pictures. That is, their grades on the two subjects were 92 and 76 percent. If they were just guessing wildly, they should have gotten scores of less than one percent, by chance.
This is the kind of finding you don’t need statistics for. True, the brain-scan data were averaged over 13 repeats of each picture for each subject; but even if they made their guess on the basis of one viewing, they still got grades of 51 and 32 percent for those two subjects—many times what you would get just by chance. And these results were achieved at what is still a very early stage in the history of brain-scanning technology. There is no telling what will be possible when resolution gets really good.
Now, true enough, these subjects had to put their heads inside a humongous donut-shaped magnet while they were doing all this, which doesn’t lend itself to convenient use in your local bar. And it cost a heck of a lot more than a penny to read their thoughts this way—more like what my mom would have called “a pretty penny.”
But the proof of principle is here and now, and the advance of technology means that we may all be subjects of brain-reading in the future.
The Berkeley researchers are fine with this, in fact they are “optimistic.” A brain decoder, they say, “would have great scientific and practical use.” We could use it “to study covert mental processes,” for instance, or to access “purely mental phenomena such as dreams and imagery.” Imagine the lie detector test you’d have for a suspected terrorist—or for that matter a prospective husband. At the extreme looms an Orwellian world in which “Big Brother”—a totalitarian government—could read the thoughts of any citizen at will.
I recently asked a group of students in a class about the brain what they thought the new field of neuroethics might be. They mentioned cases like Terry Schiavo’s, where brain science focused on whether this tragically injured woman had enough mental activity to justify keeping her on a feeding tube. Another example was the recent use of expert testimony on adolescent brain development to argue that impulse control is so weak in teenagers’ brains that the death penalty should never be applied to them. And then of course there was the not-so-simple question of figuring out whether or not someone has died.
But the thing they omitted, the thing I had to ask them about specifically, was the ethics of reading other people’s minds. I wondered aloud, “How many of you would be very worried if someone could read your thoughts?” My own hand went up first.
Millions of years of evolution have made it very hard for others to read our minds, because survival and reproduction depended on our being able to keep certain thoughts to ourselves. My mother (whose birthday would have been today) brought me up well, but my thoughts, like yours, are often selfish; I want to be judged by my actions, but I want to plan them in private.
I’m all for advancing science, and this research should go on. But I hope some very hard thinking—by ethicists as well as scientists—goes into decisions about what to use this sort of technology for, and how to control it once it’s widely available.