Scientists show how opinions trick your understanding of facts

Points of view that sound good to you seem like the truth.
Points of view that sound good to you seem like the truth.
Image: Reuters/Rebecca Cook
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You get it. Some things just make sense and you know them to be true. Or do you?

A new study, entitled “That’s My Truth,” explores the brain’s processes and how opinions can trick cognition. Examining what they call “involuntary opinion-confirmation bias,” psychologists from Ben-Gurion University and Hebrew University in Israel conclude that subjective points of view cause us to process facts more or less rapidly, and thus can hasten or get in the way of accuracy judgments.

The team conducted experiments with multiple groups of subjects. Participants had to make speedy decisions about the grammatical accuracy of sentences, and subsequently rated their agreement with the statements. The researchers then looked at the relationship between the two activities, objective and subjective, to see if subjectivity influenced cognitive processing time in the objective task.

Across the experiments, the psychologists found that participants more readily verify the grammar of a statement when it corresponds to their personal opinion. In other words, when study subjects agreed with what they read, they could also quickly determine whether the sentences were grammatically accurate. When subjects disagreed with the substance of the sentence, however, it took them longer to decide whether the grammar was correct. Brains seem to involuntarily process the factual aspects of opinion statements differently depending on the extent to which they agree with the subjective points of view.

The study, published in the April 4 issue of the journal Social Psychological and Personality Science (paywall), may help explain why people across political divides can’t agree on the meaning of, well, anything. Factual information, which on the surface seems solid—if not indisputable—is apparently subject to the involuntary processes of cognition. And the way we receive information is influenced by our opinions, or what we already believe to be true. In that case then, pretty much everything is subject to dispute.

In the first experiment, the researchers presented subjects with 88 written statements displayed in random order, half grammatically correct and the other half incorrect. The sentences appeared on screen for 2 seconds, and remained for 2 seconds after an answer was given. The subjects could all quickly judge the grammar as right or wrong to a high degree of accuracy—about 97%—making an average of only one mistake each.

After the grammatical judgment task, the statements were all presented again but every sentence was grammatically correct. This time participants rated their agreement with the statements on a 4-point scale. The researchers then correlated the two activities, looking at processing time in the grammatical judgment task and the extent of agreement expressed with the opinion statements in the second test.

The psychologists discovered that—unconsciously—the subjects took longer to answer the grammar questions when they disagreed with opinions expressed in the statements. “The results demonstrate that agreement with a stated opinion can have a rapid and involuntary effect on its cognitive processing,” they write. “Importantly, the demonstration of such a knee-jerk acceptance [or] rejection of opinions may help explain people’s remarkable ability to remain entrenched in their convictions.”

Human beings are less rational than we wish to believe, according to the psychologists. The findings are in line with previous research into the “epistemic Stroop effect,” which shows people involuntarily reject factual propositions that conflict with their worldview. “The distinction between factual truths and opinions held to be true is pivotal for rational discourse,” the team writes. “However, this distinction may apparently be somewhat murky within human psychology.”