Researchers examined how people in two age groups perceived photos of faces that had been pre-rated for trustworthiness and approachability. Although both age groups perceived faces rated as 'trustworthy' or 'neutral' as equally trustworthy and approachable, the older adults (aged 55–84, mean age 69) rated 'untrustworthy' faces as significantly more trustworthy and approachable than did the younger adults (aged 20–42, mean age 23).
Younger adults showed a strong response in a region of the brain called the anterior insula, which is known to control the 'gut feelings' that inform decision-making — especially when viewing untrustworthy faces. But the older adults displayed almost no such activation, suggesting they were getting diminished or no warning signals (abstract)."
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