There
are various ways to scan the brain. One way is to use functional
magnetic resonance imaging (fMRI), which measures change in blood
oxygenation. Then there's CT scanning, and a process called PET. Then
there's MEG, which measures magnetic fields produced by electrical
activity in the brain. Then there's NIRS, another technique for
measuring blood oxygenation in the brain.
None
of these methods give one single bit of direct information about what
someone is thinking or perceiving. However, scientists can try an
elaborate technique for matching up brain scans taken at a particular
time with data about what a person was observing at some particular
time, or what
a person says he was thinking at a particular time. It doesn't work
very well at all, because two person's brains don't look the same way
when they are thinking the same thing, or looking at the same thing.
Even a single person's brain doesn't look exactly the same way when
that person is looking at the same thing or thinking the same thought
at two different times.
But
there does seem to be a little bit of a tendency for one brain to
look a little like another brain when they are observing the same
thing or thinking the same thing. So scientists are able to do a
little bit of what I may call a parlor trick. The parlor trick
consists of analyzing sets of brain scans, and studying what a brain
scan tends to look like when a particular thought is being thought, or a
particular thing has being observed. Scientists can use that analysis
to make a very weak limited-scope prediction about a person's thought
or observations.
For
example, when a person thinks about (or observes) something burning in a
fire, his brain scan might tend to look a little different from the
way it would look if he were thinking of (or observing) someone
relaxing in an ocean. So given a set of brain readings, a scientist
or a computer might be able to say something like, “It is 20% more
likely that he is thinking about relaxing in an ocean than that he is
thinking about someone burning in a fire.”
Should
we call this type of thing “mind reading”? We should not. A
proper term for it is brain scan correlation analysis. But such a
term does not attract press attention or investors, so people doing
such brain scan correlation analysis might resort to hype, and call
it “mind reading” instead. Is there much use that we can foresee
for brain scan correlation analysis? Not really. It's probably a dead
end. It's basically a kind of parlor trick or stunt, good for
attracting a few headlines, but not much else.
In
my local library there are many Chinese books I can't read. I might
create a new technique for trying to understand Chinese. I might take
pictures of the covers of the Chinese books, and run these images
through a computer program that correlates certain pictures on the
book cover with Chinese words on the book covers. I could probably
get a few results I could brag about using such a technique, which
might attract some press attention, with headlines about a new
computer program that can read Chinese. But such a technique would
really be a parlor trick and a dead end. I would never be able to
take it much farther, and never be able to really understand Chinese
by using such a technique. Such a technique would be similar to using
our current type of brain scans to try to read minds.
The
items being read in brain scanning are like cloudy blobs, which
severely limits the amount of usable information that can be derived
from them. If you consider that the same person will have a different
set of cloudy blobs when thinking the same thing at two different
times (which would differ from the set of cloudy blobs that some
other person would produce), it is hard to foresee much use that
could be made of such analytics. One application you can think of is
creating some kind of lie detector that would work from analyzing
brain scans (because the cloudy blobs might look different when
someone is lying). But such an approach would probably not be any
more accurate than the existing technology of a polygraph.
The cloudy blobs of brain scans
The
headline in the story I have cited (referring to “the man who
records and stores your thoughts, dreams and memories”) is utterly
misleading. What is being recorded is the brain scans of people while
they are having thoughts, dreams, or recollections, not the thoughts,
dreams, and recollections themselves. The story implies that such
storage may be useful because a science of some later age may be able to
analyze the cloudy blobs of brain scans more accurately, so that they
can figure out memories, thoughts, and dreams from studying these
cloudy blobs. There is no reason to be hopeful that any such thing
will ever happen. It seems like something along the lines of saying,
“Freeze yourself at death, and science will be able to figure out
how to revive your body.” We might be able to figure out exactly
how thoughts and memories are stored in the brain, but that would
require science vastly more advanced than the crude indirect
techniques of brain scanning correlation analysis.
When
will we actually have technology for reading minds? My guess is
sometime between 50 years from now and never. Contrary to the hyped
claims of modern would-be technological mind readers, we are simply
nowhere near to understanding the mystery of how the brain stores
memories and how it produces thoughts. Our knowledge of the matter is
so limited that we are not even sure whether the brain is the sole
agent involved in storing memory and producing thoughts. We might one
day unravel such a mystery after many decades of additional study. Or
we might never figure it out.
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