Does hearing that brain scans validate a thesis inhibit critical thinking?
Yesterday in the Wall Street Journal: In “Brain Scan Overload: Don’t be fooled by pictures of the mind in action.” Jonah Lehrer sheds a little light on the real limitations of using brain scans to determine states of mind:
The problems begin, however, when researchers attempt to take complex psychological phenomena, such as the experience of love, and reduce them to particular blobs of cortex. They do this by leaning heavily on complex statistical algorithms that allow them to sort the “noise” from the “signal.”
The noise is all those changes in blood flow deemed irrelevant; it’s also the vast majority of what’s taking place. The end result is that, in many instances, the statistical filter misrepresents our neural reality, focusing on peaks of activity instead of on all the interactions that make those peaks possible. The brain isn’t simple; our pictures of the brain shouldn’t be, either.
He mentions the recent New York Times junk-scienceOp-Ed, “You Love Your iPhone,” (much decried by neuroscientists) which may have done some good if it woke people up to the manipulation potential. Because, for example,
What’s worse, the very fact that we’re looking at a brain scan seems to inhibit our critical thinking. Deena Skolnick Weisberg, a psychologist at Temple University, has demonstrated that merely referencing fMRI research can bias the evaluation of scientific papers.
When she gave neuroscience students and ordinary adults a few examples of obviously flawed scientific explanations, people were consistently able to find the flaws. However, when these same explanations were prefaced with the phrase “Brain scans indicate,” both the students and adults became much less critical.