Feeling as though nobody gets you may be linked to persistent thoughts of death.

People who frequently feel alienated , isolated and misunderstood are more likely than others to have thoughts of death and dying swirling around in their minds, new research finds. It's not yet clear whether these feelings of isolation are the cause of these morbid thoughts, though there is some tantalizing evidence that they may be.

"This is an experience that some people really have, and some people have this experience all the time," said Peter Helm, a graduate student in social psychology at the University of Arizona who led the study. "Unless we are studying it or even acknowledging it, we can't start to develop interventions for it."

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Terror and death

The new research builds on the field of terror management, which holds that humans construct careful barriers between themselves and their awareness of their mortality. Research supporting this theory has found that people reminded of death become more strongly attached to their values or cultural signifiers, perhaps as a way to find meaning in the face of their own mortality.

Helm and his colleagues were interested in exploring how a particular experience, that of existential isolation, might tie in with thoughts of death and mortality. Existential isolation is related to loneliness, but it's not the same thing, Helm told Live Science. Loneliness is a feeling of a lack of contact with others, whereas existential isolation is the feeling that other people just fundamentally don't understand you. Socializing while feeling existentially isolated can actually make the problem worse, Helm said.

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Helm and his colleagues conducted a series of four studies to determine whether existential isolation is linked to thoughts of death. In the first two, the researchers asked college students (932 in the first study and 613 in the second) to complete a questionnaire to determine their baseline levels of existential isolation, loneliness and the strength of their feelings of identity to groups larger than them. The participants also filled out a word-completion task in which they received a list of word fragments that could be made into words that did or did not relate to death, depending on the person's choice. For example, COFF_ _ could become "coffee" or "coffin." KI_ _ ED could be "kissed" or "killed."

Feeling isolated

In these studies, people who reported frequently feeling existentially isolated were more likely to create death-related words than people who weren't very existentially isolated, indicating that death thoughts were closer to the top of those isolated individuals' minds. The link between existential isolation and thoughts of death couldn't be explained by loneliness, the strength of the person's feelings of belonging to a group or self-esteem, Helm said. By contrast, loneliness, which was also linked to death thoughts, lost that link once the effects of group identity, self-esteem and existential isolation were factored in.

"It's further evidence that these are two different concepts," Helm said.

Next, the researchers tested to see if existential isolation actually causes death thoughts to bubble up. The scientists gathered 277 participants and split them into three groups. One group wrote about memories of feeling existentially isolated, one wrote about feeling lonely, and one wrote about a neutral experience of waiting for something. In that study, those who wrote about existential isolation were subsequently more likely than the other two groups to fill in the word-completion task with death-related words.

But in a follow-up study with 334 participants, the task of writing about existential isolation failed to elicit similar results.

"It opens some questions about methodological concerns about how we should be conducting these types of studies," Helm said. The second study partly consisted of people participating online, for example, who might have been more distracted or better able to comfort themselves, compared to people participating in a psychology laboratory. Alternatively, he said, the failed replication might mean that the first study was wrong and existential isolation doesn't directly trigger death thoughts.

Another possibility, Helm said, is that remembering existential isolation makes a big impact on death thoughts only for people who already tend to feel existentially isolated.

"We're looking at how this experience relates to student veterans on campus," he said. "We're seeing so far that they tend to feel more existential isolation."

The researchers are also studying how feelings of existential isolation might relate to depression and suicidal thoughts, Helm said. Psychologists have been studying loneliness for decades and have found that this emotion is linked to poor mental and physical health, he said. But existential isolation hasn't received nearly as much attention, though it seems to be a common experience. The new study, published in the October issue of the Journal of Research in Personality , was posted to Reddit recently, Helm said, and since then, he's received emails from people who have read it and wanted to say that the description of the experience rang true: They didn't feel lonely, they told him, but they did feel unseen.

"It seems like they didn't have the vocabulary to describe their experiences," Helm said.