Friday, 26 March 2010

I recently had to write a mini essay on how the mainstream press might misrepresent data from neuroimaging studies, such as functional magnetic resonance imaging (fMRI). I thought that, given the nature of the question, it might be a good thing to put up on my blog, so here it is, with a few tweaks and extra explanations of some of the terminology thrown in along the way.

How might fMRI data be misrepresented in news articles targeted to the general

Like many complex disciplines, cognitive neuroscience is plagued by misrepresentation in the media. Most journalists lack the skills, or the integrity, to identify reputable sources of research, and there is a tendency to sensationalise and exaggerate the significance of research, which falsely presents findings as a series of epoch-defining breakthroughs, which is a fundamental misunderstanding of the aggregate nature of scientific advancement. Additionally, the mainstream media reports research in isolation, detached from the context of a theoretical framework. The journalist may cite a few key comments from the author, falsely presenting scientists as infallible authority figures. Often, in an attempt to provide balance, a dissenting voice from an opposing scholar is also presented, making science appear to the public as a series of contradictory, diametrically opposed irrelevancies.

These are generic flaws of pseudoscientific journalism, whereas cognitive neuroscience is specifically vulnerable to misrepresentation. This is because it is is a field in which the public has a great interest, but very little knowledge. This enthusiasm for neuroimaging is understandable, as cognitive neuroscience examines intrinsically human topics, such as consciousness, personality, and emotion. Because of the perceived impenetrability of the brain in the public consciousness there is a tacit belief that this research is utterly incomprehensible, leading to ready acceptance of the press reports without critical appraisal. For example, research has shown that presenting an image of a brain in an article will make the scientific credibility of the research appear greater to the reader (McCabe & Castel, 2008). A similar effect has been demonstrated when neuroscientific terminology is inserted into an article, even when it bears little relevance to the discussion (Weisberg, Keil, Goodstein, Rawson, & Gray, 2008). Clearly, this mystification of brain function amongst the public is open to abuse, deliberate or unintentional.

Reports of fMRI in the press tend to be overly optimistic about its potential, fail to explain its limitations, and are not sufficiently critical of the methodology (Racine, Bar-Ilan, & Illes, 2005). This problem is exacerbated by the contention that much fMRI data has already been distorted and excagerated by the researcher, knowingly or otherwise (Vul, Harris, Winkielman, & Pashler, 2009). This means that the general public, who are untrained in how to critically appraise neuroscientific research, are often presented with news reports which bear little resemblance to the true results

(At this point, I will interject to remind you about the difference between forward and reverse inferences. A forward inference is when the researcher plots in advance what brain activation they expect to see when a person does a given task in the scanner. This might be as simple as "the participant will do a language task, so we expect to see the left posterior section of the superior temporal gyrus activated, because this is where we process and understand language". This kind of inference is not perfect, but it is better than the alternative, because we are making and testing a prediction.

The alternative, the reverse inference, is severely frowned upon in cognitive neuroscience. Imagine we did the experiment I just described, and as well as activation in the superior temporal gyrus we also saw activation in several other areas which we were not expecting to be activated. We could not then start to speculate on why these other areas were activated, because brain areas often have more than one function, so guess work is considered very bad science indeed. With that little aside out of the way, you should all be able to follow my next point!

Additionally, the fallacy of reverse inference, avoided by credible neuroscientists, still appears viable to laypeople, especially given the popular myth that we humans only use 10% of our brain (this is not true - every part of the brain has a known function). This myth masks the complex and multipurpose nature of brain function, supporting the notion that brain activity is easily attributable to specific cognitive functions.

Racine, Bar-Ilan, and Illes (2005) examined the portrayal of fMRI research in the media, and identified three key trends, “‘neuro-realism’, ‘neuro-essentialism’ and ‘neuro-policy’” (p. 2). Neuro-realism, they claim, is the phenomenon whereby subjective findings falsely appear as objective fact when viewed within the context of a neuroimaging study. The second, neuro-essentialism, describes the tendency to attribute a self or personality to the brain itself, almost to the point where the brain is depicted as being self-aware, admonishing the individual from any degree of control. Finally, neuro-policy is the politicisation of neuroscientific research to fit and reinforce a social or political agenda. Taken as a whole, these trends misrepresent the findings and usage of fMRI in cognitive neuroscience, ignoring its true purpose as a scientific tool to devise and test hypotheses, and to detail the true workings of the mind and brain.


McCabe, D. P., & Castel, A. D. (2008) Seeing is believing: The effect of brain images on judgments of scientific reasoning. Cognition, 107, 343-352.

Racine, E., Bar-Ilan, O., & Illes, J. (2005). fMRI in the public eye. Nature Reviews Neuroscience, 6(2), 159-164.

Vul, E., Harris, C., Winkielman, P., & Pashler, H. (2009). Puzzlingly high correlations in fMRI studies of emotion, personality, and social cognition. Perspectives on Psychological Science, 4(3), 274-290.

Weisberg, D. S., Keil, F. C., Goodstein, J., Rawson, E., & Gray, J. R. (2008). The seductive allure of neuroscience explanations. Journal of Cognitive Neuroscience, 20(3), 470-477.

There you go, I hope you will all now be a little more sceptical next time you see an astonishing revelation about the brain on the news or in the paper!

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