In other words, the brain activity of voters who claimed not to like Edwards reflected that dislike. But the brain activity of voters who didn’t give him low marks reflected empathy for, and connection with, the candidate. Hence, “promise” as well as “problem”: reactions to Edwards were a mixed bag.

But here’s the summary of the brain-on-Edwards, according to the article’s graphic:

Subjects who had an unfavorable view of John Edwards responded to pictures of him with feelings of disgust, evidenced by increasing activity in the insula, a brain area associated with negative emotions.

Hmm. Where’s the stuff about empathy and connection? It’s missing entirely from the graphic’s caption. Which is a big deal, because these graphics function not merely to attract the eye, or to break up the gray of the page; they’re meant to convey the article’s content. (The piece’s layout reinforces that role: the brain-imaging graphics, in terms of both size (huge) and page placement (center), get bigger play than the article text itself.) But if readers look only at the graphic, they’ll come away associating Edwards with “disgust”—a deceptively skewed conclusion.

That’s not the only discrepancy. Mitt Romney’s summary, in the text of “This Is Your Brain,” reports that viewing still photos of the candidate elicited anxiety in voters’ brains—but also that “when the subjects saw him and heard his video, their anxiety died down.” The article’s Romney graphic, though, notes simply that “looking at photos of Mitt Romney led to activity in the amygdala, a brain area linked to anxiety” (and then punctuates that point with an amygdala-activated brain illustration and the aforementioned “anxious man” icon). The graphic mentions nothing about that initial anxiety being ameliorated through seeing and hearing Romney on video—the more politically salient fact here, given that voters are almost guaranteed to see the candidate in video form over the course of the campaign. Similarly, watching video of Barack Obama, the article reports, provoked “increased activity in some regions of the brain associated with positive feeling” among male subjects (though not so with women); the Obama graphic, however, notes only the subjects’ reactions to photos of him—and the fact that, when shown those pictures, voters “had little activity in areas of the brain associated with thought or feeling.” Again: hmm.

If an article purports to “reveal some voter impressions on which this election may well turn,” it needs to reflect those revelations at every turn—not just in its text, but in the entire package it presents to its readers. The brain-drainy graphics “This Is Your Brain” serves up serve as a useful reminder: graphics need to be able to stand independently from the articles they illustrate; they should complement an article, certainly, but never contradict it. There’s no gray area in that—even, and especially, when it comes to gray matter.

Megan Garber is an assistant editor at the Nieman Journalism Lab at Harvard University. She was formerly a CJR staff writer.