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Critical Thinking: Needed Now More Than Ever
The truth is that neuroscientists are dealing with correlational data, and if some area is
activated during some psychological process, it could mean any number of things: It may
be the sole locus of the operation; it may have been disinhibited by some other area that is
of equal or greater importance even though that other area is not as active; it may be nec-
essary for the mental operation but not sufficient unless other areas, including areas of
lesser activity, are also involved; it may contain neurons that operate less efficiently than
do those in other areas, and that therefore must consume more energy; and so on. What
this means is that it is hard to know whether the image in a brain scan actually gives us a
“picture” of the neurodynamics of the operation in question. All of these caveats fly out
the window, however, when the media jump on some finding, especially if it has to do
with something that captures the public’s imagination, such as sex differences or spiritual
experiences.
The issues I have discussed, both methodological and conceptual ones, are not aca-
demic. Increasingly, brain scans are being used in ways that those doing the original
research may never have anticipated or desired. For instance, brain scans are starting to be
introduced as evidence in court cases to argue for diminished responsibility and are being
promoted as “lie detectors” in criminal cases; one commercial company has even begun
offering a brain-scan test for deception, and the Defense Department and CIA have
reportedly invested millions in neuroimaging technologies that might be used in law
enforcement or intelligence. But because of the normal variability among people in their
brain responses, innocent but highly reactive people may be mislabeled “guilty” by these
seemingly scientific tests, just as has happened in the use of the polygraph and other methods
that assume the existence of universal biological responses in emotional states.
Thus we need to teach our students to think critically in part so they can separate the
wheat from the chaff in our own field of psychology. If they intend to become thera-
pists, they will understand that good therapy and an appreciation of research are not
mutually exclusive. If they intend to use the techniques of neuroscience, they will under-
stand that science is not merely a matter of technique; it is rooted in an attitude toward
evidence and interpretation—an attitude that requires critical thinking at every stage of
the process.
Barriers to Critical Thought in the Culture
There is also a larger picture to consider, for the existence of uncritical thinking within our
own field is occurring in a culture that is often distrustful of science and relativistic in its
thinking about scientific and nonscientific claims. We hear this distrust and relativism
when our students say, “Well, that’s just my opinion,” as if all opinions were created
equal—end of discussion.
Relativism has found expression in the renewed debate about the teaching of creation-
ism, now repackaged as intelligent design, in our public schools, as a counterpoint to
evolution. I would certainly never fault a person for having religious faith, and I think a
good argument can be made that there is no necessary conflict between evolution and
religion as broadly construed. No less a scientist than Francis Collins, Director of the