Brainwashed: The Seductive Appeal of Mindless Neuroscience
Sally Satel Scott O. Lilienfeld
Basic Books, 2013 ($27.99)

Frito-Lay, the snack food giant, wanted to sell more potato chips to women. So it commissioned a neuroimaging study, which found that women looking at a shiny bag of potato chips had increased activity in the anterior cingulate cortex, associated with guilt. In the hopes of boosting sales, Frito-Lay switched to matte bags.

But how savvy was this swap? Not very, suggest psychologists Satel and Lilienfeld (the latter serves on the board of Scientific American Mind) in Brainwashed, which documents the rise of overhyped neuroscience. Activity in the anterior cingulate cortex also correlates with pain, decision making and motivation. The case is a classic example of reverse inference, the assumption that you can guess what someone is thinking by observing which brain region lights up on a scan.

Technologies have revolutionized the field of neuroscience. Yet scientists, lawyers and advertisers are increasingly using brain scans to make sweeping conclusions about our mental states and intentions, often leading to oversimplified or flawed explanations of the brain, Satel and Lilienfeld caution.

Reverse inference is just one of several common errors. A second pitfall is neuroredundancy, which uses neuroscience to reveal an obvious detail. Most of us can gather that a teenage defendant is immature, for example, without brain scans.

In other cases, neurohype has overstated how the brain influences behavior. Calling addiction a chronic brain disease was intended to reduce stigma—so addicts would not be accused of having a weak character—and to refocus research on brain-level explanations and treatments. Yet this approach downplays the complexity of addictive behavior and inadvertently created a new stigma, by associating addiction with mental illness.

These reasoning errors are founded on a mistaken assumption that the brain dictates every aspect of behavior. Such a claim, the authors argue, undermines the existence of free will and personal accountability.

Throughout Brainwashed, the authors give credit where credit is due, describing how imaging has illuminated the structure of the brain. They also explain that probing the brain is just one way to unravel how the mind works. It is this desire to understand the intricacies of what makes us us that keeps science endlessly exciting.