Let's say you have an identical twin. You grow up in the same house, probably attend the same school, obviously share the exact same genes. But you become the target of a bully during your pre-teen years, while your brother or sister somehow escapes the taunts and abuse. The next two years may start to look very different for you and your sibling, according to results of a new study in JAMA Psychiatry.
In the group of more than 11,000 twins, those who were bullied at age 11 were more likely to have a wide range of troubles by the age of 13 than their non-bullied siblings. They were more often anxious and depressed, and even had more paranoid thoughts and showed other early signs of more severe mental illnesses like schizophrenia. Though the effects faded as time passed, some still surfaced when the researchers checked in with the traumatized teens again at age 16.
The results don't come as a huge shock to anyone on the receiving end of playground taunts, lunchroom slights, or online threats—nor do they surprise mental health experts who study or treat these consequences. "The acute effects of bullying happen and they tend to persist; we've known that for a long time," says Mark Reinecke, chief of psychology at Northwestern University Feinberg School of Medicine in Chicago. "But this is shining an ever-clearer light on that."
Previous research has traced bullying's destructive path into young adulthood—and beyond. In a study published last year, undergrads bullied during childhood had higher rates of depression, anxiety, and post-traumatic stress disorder. Authors of a 2015 paper in the BMJ with similar findings suggest that, if there's truly a direct cause-and-effect link, as much as 30 percent of the depression that occurs in early adulthood could be attributed to bullying during teenage years.
Some research even shows victims have more troubled relationships, worse physical health, and trouble keeping jobs or making ends meet by their mid-20s—and on into their 50s. Bullies don't fare much better. Aggressors have also been shown to have poorer mental and physical health years later, and may have a greater risk of later criminal activity, according to Mary Muscari, a forensic psychiatric nurse and criminologist at Binghamton University.
Often, victims become bullies themselves, and that dual role seems to land them in the highest risk category of all. For instance, another recent JAMA Psychiatry study found that about 31 percent of people who were bullies and victims at age eight received a psychiatric diagnosis by age 29—compared to only 23 percent of victims and 11 percent of those who managed to stay out of the fray.
In a book published last year—Bullying Scars: The Impact on Adult Life and Relationships—Syracuse University researcher Ellen deLara interviewed 800 adults about bullying and coined a new term for these types of consequences: adult post-bullying syndrome.
Scientists are still working to understand the exact mechanisms by which this constellation of effects occurs. Repeated exposure to the worst of your peers may permanently alter the way your body responds to stress, boosting your levels of stress hormones like cortisol, Reinecke says. Bullying and other forms of violence might even cause changes deep down in your DNA, shortening aging-related snippets called telomeres, found research from Duke and King's College London.
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"Bullying or stressful life events can have an effect on brain development, on cognitive development, and on the types of the beliefs and attitudes and coping strategies that a child develops," Reinecke says. And even if you change schools or the bully moves away, you might never see the world exactly the same.
Brain studies have begun to bear this out, says researcher Johanna Jarcho, who conducts them at Stony Brook University. When she put persistently shy 11-year-olds (common bully targets) through an fMRI scan while they experienced a virtual model of bullying—a clever way to mimic taunting in a long, metal tube—she found their brains reacted differently not to the bullying itself, but to unexpected positive feedback.
Specifically, they saw a different reaction in shy kids' amygdalas, an area of the brain responsible for things like processing threats and rewards. The bigger the difference in activation, the greater the risk that child had for displaying social anxiety.
"What we think might be happening for these victimized kids who already have this other kind of vulnerability due to their early childhood experiences is that they might be kind of encoding these positive experiences in a different way that could potentially be detrimental," she says. In other words, bullying may scramble the signals your brain sends in response to every social interaction, leading you to fear even those who might reach out in friendship.
Her work highlights another important aspect of the long-term harms of bullying. "Youngsters and teens who are bullied aren't randomly selected," Reinecke says. Bullies pick on kids who are different in some way—and those differences themselves, whether in personality or appearance or social skills, may also predispose kids to later struggles. As Jarcho's research highlights, the combination of the two can lead to a one-two punch, a compounded detrimental effect on mental health and functioning.
It's a cruel calculus. But the new study does provide some hope in that, on average, the negative effects diminished after five years. "It was quite encouraging for us, because it means that children who are bullied, they might have the chance to return to normal functioning over time," says co-author and University College London researcher Tabea Schoeler. Future treatment approaches, then, could work to build the resilience of kids who were already bullied, in addition to preventing bullying itself.
Jarcho agrees: "We talk in these generalities about how anyone who's victimized ends up having a negative consequence. On average that might be true, but there's a lot of individual variation within that," she says. Her work and others' hope to illuminate those differences, to learn how to protect the vulnerable and boost everyone's ability to cope.
Right now, we know having a few good buddies or even a single best friend may reduce the impact of bullying both in the short and long term. So can playing sports, joining a group, or learning other ways to cope, Reinecke points out.
In some people, overcoming the obstacle of bullying can pay dividends later on; in Bullying Scars, deLara reports that nearly half of the people she interviewed reported some positive consequence to their bullying experience, such as enhanced empathy, a greater drive to reach their goals, and more confidence in their ability to handle whatever life brought their way.
If these positive effects can be harnessed and combined with the types of systemic changes many schools have implemented to cut back on bullying, Jarcho says, things just might look rosier for the kids and teens of the future.
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This article originally appeared on VICE US.