The Meme Machine

TAKING THE MEME’S EYE VIEW 39
events with new endings, self-justifications, complicated plans for the future, or
difficult decisions that have to be made. They are rarely simple images,
perceptions or feelings (which can come and go without causing trouble); rather,
they use words, arguments, and ideas you have acquired from other people. In
other words, these incessant thoughts are memes. ‘You’ cannot command them
to cease. You cannot even command them to go slower nor tell yourself not to
get sucked into them. They seem to have a life and power of their own. Why?
From the biological point of view this constant thinking does not appear to be
justified. I say this cautiously, in the recognition that many things that at first
did not appear to be in the interests of the genes subsequently have turned out to
be. Nevertheless it may be helpful to think this through.
Thinking requires energy. One of the many benefits of techniques like PET
scanning (positron emission tomography) is that we can observe graphically
what goes on in a brain when someone is thinking. Scans, although still
severely limited in resolution, can show the relative amounts of blood flowing in
different areas of the brain. For example, when someone is doing a visual task
there is more activity in the visual cortex, when listening to music more in the
auditory cortex, and so on. As had long been suspected, imagining something
uses similar parts of the brain as actually seeing or hearing the same thing. So
imagining conversations activates speech areas, and so on. Experiments
comparing simple usual tasks with more difficult ones show higher levels of
activity with the more difficult task.
The amounts of energy used are small compared with, say, running up a hill,
but they are not entirely negligible. Blood flow means that oxygen and stored
energy are being burned up, and these have to be worked for. If an organism
could get by without thinking all the time it would use less energy and hence
ought to have a survival advantage.
Presumably, then, all this thinking has some function. But what? Perhaps
we are practising useful skills, or solving problems, or thinking through social
exchanges so as to make better deals, or planning future activities. I have to say
this does not seem to be plausible for the sorts of daft and pointless thoughts I
tend to think about. However, applying evolutionary thinking to today’s
situation may not be appropriate. We did not evolve along with books,
telephones and cities.
Evolutionary psychologists would suggest that instead we consider our
hunter-gatherer past. Speculating in too much detail is dangerous since we have
rather little information about the far past, but many authors have provided good
descriptions based on the available evidence (Dunbar 1996; Leakey 1994;