With colleagues at Scotland’s University of Aberdeen, Ray ran four experiments that measured how people interpret forgetting. One had 56 students keep online “diaries” at the beginning of the school year, asking them to detail every single time they were forgotten. Their entries, recorded daily for two weeks, captured all the ways forgetting can play out. For the most part, it was loose acquaintances forgetting basic facts—names, class years, majors—or experiences they’d shared with the diary keepers, like attending the same party. But there were also broken commitments (“My friend was supposed to meet me at the library today”), dramatic exclusions (“My friends organized a night out and forgot to ask me”), and confusions of one person for someone else.

Ray and his team were surprised by how consistently damaging all this forgetting was. Statistical analyses of both the students’ reports and a follow-up, controlled study found that people who were forgotten felt less close to those who had forgotten them, regardless of whether the forgetter was a family member or someone they’d just met. Mercifully, the people who were forgotten were almost always eager to excuse the memory lapses: The university students, for instance, would explain away potential slights with comments like “she already met too many people in the last couple of days.” But such rationalizations only softened the blow in the end. “The good news is that this happens a lot, and people will try their best to be forgiving,” Ray says. “The bad news is that, on average, they can’t quite get there.”

These results, published in the Journal of Personality and Social Psychology, suggest that forgetting someone does indeed send the message everyone seems to fear it does: You simply weren’t interested or invested in that person enough to remember things about them. The impression might be inescapable. “It’s such a big deal to admit that you don’t remember a person,” says Laura King, a psychologist at the University of Missouri who has separately studied the social consequences of forgetting. “It’s an insult, even though it’s completely innocent and we have absolutely no desire to hurt the person’s feelings. You just told that person they’re a zero.”

In a subtle way, doing so might harm the people who are forgotten, on top of their relationships with the forgetters. Ray’s team asked the research subjects to do a little soul searching during the experiments, instructing participants to rate their general feelings of belonging, self-esteem, meaningful existence, and other abstract emotions after they were forgotten or remembered. The effects were marginal but reliable: People who were forgotten reported decreased senses of belonging and meaning in the world. It was as if they’d received an ever-so-faint existential zap.