Why do your grandparents keep falling for email scams?S

We've all heard tales of elderly friends and relatives who have fallen for financial scams. Pyramid schemes, Nigerian emails, dodgy "computer repair" calls, you name it. That said, there may be a reason for it — a scientific explanation for how we get scammed more easily the older we get.

A new article published in PNAS describes how as we get older, our ability to detect "untrustworthiness" seems to decay.

Why do your grandparents keep falling for email scams?S

The research hinges on our abilities to recognize "trustworthy" and "untrustworthy" faces. They took cohorts of younger and older adults, and asked them to rate faces as being trustworthy, neutral, or untrustworthy. While both age groups were just as good for labeling people as trustworthy or neutral, when it came to untrustworthy, the groups split — the older participants were less likely to flag those faces as dishonest.

The same test was run, but with new participants hooked up to fMRI scans. What the researchers discovered was that the older group (mean age of 66) had less activity in their anterior insula than the younger group (mean age of 33). This is an area of the brain related to perceiving risk and producing visceral warning signs like disgust and "gut instinct".

Essentially, as we get older, we get less good at identifying is someone — or something — is trustworthy or not. Which in and of itself should be enough for pause when reaching for the checkbook.

Top image: Shutterstock.com. Bottom image: Oosterhof & Todorov