fMRI Studies Overrated?
A provocative article in Seed by Yale’s Paul Bloom, Seduced by the Flickering Lights of the Brain, suggests that scientists are getting carried away with their reliance on fMRI studies.
…This is more than just phrenology. But it is not so dazzling that it should usurp other areas of research.
FMRI studies?which indirectly measure the flow of oxygenated blood in the brain?are typically motivated by earlier experiments that used more conventional methods, and are not always a better window to the soul than eye tracking, behavioral genetics, implicit priming or dozens of other well-worn techniques. We know far more about the mind from the study of, say, reaction times than we do from fMRI studies.
Psychologists can be heard grousing that the only way to publish in Science or Nature is with pretty color pictures of the brain. The media, critical funding decisions, precious column inches, tenure posts, science credibility and the popular imagination have all been influenced by fMRI’s seductive but deceptive grasp on our attentions. It’s a pervasive influence, and it’s not because the science is better.
To some degree, the same general phenomenon can be observed in the more narrow use of fMRI scans in neuromarketing. Flashy, full-color pictures sometimes obscure the fact that the actual marketing conclusions that can be drawn from the work are tenuous at best. Certainly, some of the widely touted fMRI-based ad studies have been weak science and weak marketing, but excellent public relations.
Bloom thinks there’s so much emphasis on fMRI “because fMRI seems more like real science than many of the other things that psychologists are up to. ” That may be one reason, but I think the reason fMRI gets so much attention is that it provides scientists and others with a real window into the real-time functioning of specific brain areas. fMRI is one of the first and best windows into the black box of the human brain. Indeed, most types of study cited by Bloom – eye tracking and reaction time studies, for example – do treat the brain as a black box and measure only inputs and outputs. That doesn’t mean these kinds of studies aren’t useful, or even better for many kinds of research, but it’s easy to understand why scientists want to peer inside and see exactly how those inputs are turned into specific outputs.
The fact is that our current ability to both capture and interpret real-time brain activity images may be way ahead of where we were a decade ago, but still has a considerable distance to go before we can achieve more than a definitive understanding of how brain activity translates into behavior. We are certainly moving in the right direction, though – as the spatial and temporal resolutions of brain scans improve, and as more researchers continue to explain specific chunks of behavior using the scan data, our ability to develop more comprehensive models and more accurate behavioral predictions will increase quickly.
Comments on Bloom’s assertions are appearing on the Web. Scientifically Minded called Bloom’s comments, “fightin’ words.” Small Gray Matters confronts Bloom head-on, with a lengthy and well-informed refutation of many of Bloom’s points. Mixing Memory agrees with Bloom, calling cognitive neuroscience “a fad that I hope will soon die off, or merge into psychology and neuroscience proper.”
Whatever the future may hold, Bloom’s point that the current state of fMRI studies may be over-hyped should be heeded by marketers. As with scientists, today’s marketers should avoid being seduced by brain images that suggest it’s now possible to read the minds of customers. Rather, brain scans should be used in conjunction with more established techniques, and the conclusions reached should be considered tentative until a strong correlation is established with real-world behavior.