If you didn't play sports growing up, it's possible that all you know about concussions comes from that one scene in 10 Things I Hate About You. A brain injury can cause confusion, blurred vision, dizziness, and other potentially dangerous side effects, but one thing that's rarely (as in, very rarely) talked about when it comes to concussions is how brain injuries can affect your mental health in unexpected and serious ways.
Study after study has confirmed that after a traumatic brain injury, or TBI, peoples' emotions tend to change — and that depression and anxiety often develop as they're recovering. One study in 2004 found that up to a third of their patients recovering from TBI seem to experience major depression in the immediate recovery period, and that went up to about 42 percent a year afterwards. Their risk of depression also spiked if they'd experienced mood disorders before their injury. Another study in 2010 found that 53 percent of their patients experienced major depression in the year after their injury. But what's happening in the brains of people with injuries to increase the risk of depression or anxiety?
"Traumatic brain injuries can damage or alter cellular pathways in the brain," psychiatrist Dr. Jared Heathman tells Bustle. "These changes can cause many symptoms including decreased concentration, impaired impulse control, and forgetfulness, to name a few." And that can be very psychologically damaging. "Dysfunction can lead to decreasing self-esteem and hopelessness that life will not improve. Worrying about the brain injury and its effects can potentiate other worries." In other words, someone with a brain injury can experience anxiety around their more commonly-known symptoms, and the idea that those symptoms may be around forever.
But there are other ways in which mood disorders can be "sparked" by a TBI. "In many cases, a brain injury can change the way people feel or express emotions," Dr. Michael Lavoie, a professor at the University of Arizona College of Medicine — Phoenix and clinical director for neuropsychology at Barrow Neurological Institute Phoenix Children’s Hospital, tells Bustle. "TBI patients can have difficulty controlling emotions and may develop mood swings. Some people may experience emotions very quickly and intensely but with very little lasting effect," he says. These swings are a result of direct damage to the brain's emotional processing centers, says Professor Lavoie, and can lead to social isolation when the support network of the person experiencing mood swings doesn't understand how to help them.
Furthermore, damage to the physical structures of the brain that affect emotions can trigger these mood changes. A study in 2015 found that people with depression after a TBI had much less functional "white matter," or nerve tissue around the brain's neurons that allow electrical signals to be transmitted between cells, than other TBI patients. This suggests that mood disorders after a brain injury have to do with a communication problem, as neurons struggle to connect properly. People with depression after a TBI, according to research from 2015, show a different pattern of connections in their brain; scans of their brains showed lower connectivity between the amygdala, which has a big role in emotional regulation, and other areas of brain tissue, like the insula, prefrontal cortices, and parietal lobules. The patterns in which a brain has been injured or concussed may have an impact on how it processes emotions afterwards. Damage the wrong part, and your mood may be affected as the brain tries to repair itself.
Genetics and inflammation can also play a role. A 2018 study of veterans with mood disorders, including anxiety, following TBI found that people with a particular genetic variant, one that regulates how the body repairs neurons, had a higher risk of serious mood symptoms. And inflammation also seems to be implicated. A study of football players in 2015 found that chronic inflammation levels in their brains after an injury seemed to contribute to issues like depression.
If this is happening to you or somebody you know, it's important to remember that this isn't unexpected; in fact, it's very common. "Statistically, about half of all people with TBI are affected by depression within the first year after injury, and nearly two thirds experience it in the seven years afterwards," Professor Lavoie tells Bustle. "More than half of the people with TBI who are depressed also have significant anxiety." It's a tangled knot, but science is helping us to understand it, bit by bit. And at the moment, there's still a lot of work going on to figure out how to best treat mood issues after a TBI, particularly when there's physical brain alteration involved. One study in 2009 found that anti-depressants and cognitive behavioral therapy seem to have the best results. As with all mood disorders, it seems, there are treatment options for people to find their equilibrium again.
Correction: This story was updated to more accurately reflect Dr. Michael Lavoie's title.