Nonprobative photographs (or words) inflate truthiness

Abstract

When people evaluate claims, they often rely on what comedian Stephen Colbert calls "truthiness," or subjective feelings of truth. In four experiments, we examined the impact of nonprobative information on truthiness. In Experiments 1A and 1B, people saw familiar and unfamiliar celebrity names and, for each, quickly responded "true" or "false" to the (betweensubjects) claim "This famous person is alive" or "This famous person is dead." Within subjects, some of the names appeared with a photo of the celebrity engaged in his or her profession, whereas other names appeared alone. For unfamiliar celebrity names, photos increased the likelihood that the subjects would judge the claim to be true. Moreover, the same photos inflated the subjective truth of both the "alive" and "dead" claims, suggesting that photos did not produce an "alive bias" but rather a "truth bias." Experiment 2 showed that photos and verbal information similarly inflated truthiness, suggesting that the effect is not peculiar to photographs per se. Experiment 3 demonstrated that nonprobative photos can also enhance the truthiness of general knowledge claims (e.g., Giraffes are the only mammals that cannot jump). These effects add to a growing literature on how nonprobative information can inflate subjective feelings of truth.

Nonprobative photos rapidly lead people to believe claims about their own (and other people’s) pasts

“…When people evaluate general knowledge claims (e.g., Macadamia nuts are in the same evolutionary family as peaches) that they know are a mix of true and false, they more often endorse claims that appear with related, but nonprobative, photos (e.g., a photo of macadamia nuts; Newman, Garry, Bernstein, Kantner, & Lindsay, 2012). But these findings cannot tell us whether photos similarly distort people's judgments about their personal pasts.…”

“…We used unfamiliar animals for two reasons. First, the effects of nonprobative photos tend to be more powerful for judgments about unfamiliar stimuli (Newman et al, 2012). Second, we wanted to make it difficult for people to encode the events well because the test phase happened soon after the study phase, and there is evidence that well-encoded experiences are less susceptible to the influence of nondiagnostic feelings than are poorly -encoded experiences (Monin, 2003;Zaragoza & Lane, 1998).…”

On the (non)persuasive power of a brain image

“…Manipulations like these that boost comprehension can also make other concepts related to the material feel more easily available in memory, and we know that people interpret this feeling of ease as diagnostic of familiarity and truth (Newman, Garry, Bernstein, Kantner, & Lindsay, 2012;Tversky & Kahneman, 1973;Whittlesea, 1993;see Alter & Oppenheimer, 2009, for a review). But a brain image depicting activity in the frontal lobes is different.…”

Evidence that photos promote rosiness for claims about the future

“…We also know from recent work that nonprobative photos can more rapidly nudge people to find associated claims true (Fenn, Newman, Pezdek, & Garry, 2013;Newman, Garry, Bernstein, Kantner, & Lindsay, 2012). In this paradigm, people quickly judge a series of trivia claims (The liquid metal inside a thermometer is magnesium) as true or false.…”

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Abstract When people rapidly judge the truth of claims about the present or the past, a related but nonprobative photo can produce Btruthiness,^an increase in the perceived truth of those claims (Newman, Garry, Bernstein, Kantner, & Lindsay, 2012). What we do not know is the extent to which nonprobative photos cause truthiness for the future.

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