This study seemed like it was begging to be done, so I figured somebody must have done it already. Thank you Google Scholar for helping me find it…
Seeing is believing: The effect of brain images on judgments of scientific reasoning [pdf]
David P. McCabe and Alan D. Castel
Brain images are believed to have a particularly persuasive influence on the public perception of research on cognition. Three experiments are reported showing that presenting brain images with articles summarizing cognitive neuroscience research resulted in higher ratings of scientific reasoning for arguments made in those articles, as compared to articles accompanied by bar graphs, a topographical map of brain activation, or no image. These data lend support to the notion that part of the fascination, and the credibility, of brain imaging research lies in the persuasive power of the actual brain images themselves. We argue that brain images are influential because they provide a physical basis for abstract cognitive processes, appealing to people’s affinity for reductionistic explanations of cognitive phenomena.
For a few years now I’ve been joking that I should end every talk with a slide of a random brain image, and conclude, “Aaaannnd… all of this happens in the brain!” This is solid evidence that doing so would help my credibility.
Now, the next big question is: who’s going to replicate this with psychologists and neuroscientists as the subjects?
The Hardest Science 
I love this study! Thanks for the sweet post.
Another strange aspect of the power of brain pictures is the credibility shift that tends to come along with presenting different kinds of images of the brain. If you show an SPM (those ubiquitous 2-D greyscale images with white->yellow->orange->red blobs), it’s widely regarded as completely legitimate, but if you do a more aesthetically appealing presentation with 3-D renderings, you can catch flak for being “too flashy,” and are sometimes assumed to be dressing up bad data with pretty pictures.
So brain pictures are good, but really good brain pictures are bad? It’s a tough nut to crack…
This Weisberg paper below is also pretty neat. It’s about the way that presenting irrelevant neuroscience information alongside psychological explanations tends to make people rate good explanations as even better while bad explanations are rated as worse when not accompanied by some sort of neuro story. This holds true for laypersons AND neuroscience students (although a reverse pattern is seen in neuroscience experts, who assign less credibility to explanations with irrelevant neuro info):
Skolnick Weisberg, D., F.C. Keil, J. Goodstein, E. Rawson, and J.R. Gray. 2008. The seductive allure of neuroscience explanations. Journal of Cognitive Neuroscience 20: 470–477.
It’s always amazing to me how “It happens in the brain!” is a satisfying explanation to freshman, but the seniors smugly know that the freshmen are wrong… and think that “It happens in the limbic system” is a perfectly reasonable explanation for so many psychological phenomena….
they have to wait until they are beginning graduate students to advance to… “It happens in the amygdala”
I love those two articles though. I am going to save them and give them to some special future undergraduate who asks, “yeah, but what does it really mean that the amygdala ‘lights up’?” (Here, take this red pill…)
Interesting. Pretty multi-color 3-d pictures can be a bit tiresome after a while in scientific papers when a simple graph will do. I think there is a cynical impulse for a scientist to use them gratuitously in order to subconsciously bolster claims, impress grant and awards committees, and impress the public who won’t understand it but at least they get a pretty show.