Members in the Media
From: Forbes

The World’s Getting Better. Here’s Why Your Brain Can’t Believe It.

Life has improved for most people around the world over the past generation, temporary pandemics aside. The rub is that you can’t get anyone to believe the good news. And the result is a toxic political environment—and the potential collapse of democratic norms if too few people feel that a stressed system is worth saving.

Those on the right tend to be certain that crime and unauthorized immigration are growing out of control, in the face of statistics showing the opposite. Those on the left tend to be certain that racism, sexism and oppression are growing worse, which comes as news to the people on the right who claim to be choking on the fumes of political correctness.

David Levari, a psychologist at Harvard University working under the legendary Daniel Gilbert, collaborated with Gilbert and others on this study illustrating the human brain’s faulty perception.

Our Awareness of a Signal Grows Even as the Signal Wanes

Published in Science in 2018, the study found that “when the ‘signal’ a person is searching for becomes rare, the person naturally responds by broadening his or her definition of the signal—and therefore continues to find it even when it is not there.”

In one set of experiments, participants were presented with hundreds of series of dots, ranging in color from highly blue to highly purple. They were instructed to look for and identify dots that they judged to be blue. Within groups that were gradually presented with a lower frequency of bluish dots, their definition of blue gradually expanded. By the end of the experiment, they identified some dots as blue that they would not have identified as blue at the outset.

In a variation, some participants were informed beforehand that blue dots would be presented with decreasing frequency. Yet even armed with that knowledge, they continued subconsciously to broaden their perception of blue.

In another variation, some were explicitly told to avoid the temptation to broaden their judgment of which dots could be classified as blue—and others were even offered a $10 bonus if they could avoid doing so. Still, as blue dots became less prevalent, participants adjusted by seeing blue where they previously hadn’t seen it.

Levari and his colleagues ran a similar experiment involving more subjectivity and complexity: They presented participants with images of faces that had previously been rated as threatening or nonthreatening, and asked them to identify the threatening ones. Again, they found, “when the prevalence of threatening targets decreased, participants’ concept of threat expanded to include targets that it had previously excluded.”

And in one even more complex variation, they asked participants to evaluate a number of scientific study proposals that had previously been rated as more ethical or less ethical, and to identify which ones they would personally be willing to approve. As they decreased the prevalence of unethical proposals presented to some participants, they found that these participants began to broaden their definition of what seemed unethical.

Read the whole story (subscription may be required): Forbes

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