Why Does a Brain Injury Cause Behavioral Changes?


Why does a brain injury cause behavioral changes?


Click here to see other video Q&As with Heechin Chae, MD.

Click here to return to our BrainLine Military Ask the Expert feature.

[Dr. Heechin Chae] By definition there's some physical injury to the brain. But that leads to neurotransmitter, neurochemical changes in the brain. And part of that response to those changes the brain goes through is really going into more—I call it "more protective state." I call it "defensive state"—trying to protect itself from further injury. Part of that defense mechanism is being super alert—paying attention to sensory, internal, environmental inputs that the brain receives constantly that we're not even aware of. Paying more attention to those—really paying more attention than it should, such as when I'm sitting in a chair like this, I'm supposed to feel pressure on my legs and the bottom, too, because the chair is pushing up against my body. But I ignore that. The brain actually learns to ignore those things because that's not dangerous—that's not important because talking to you right now is the most important thing. So the brain actually helps me focus on that rather than focusing on other things that my brain is being aware of. What we're learning is that after injury like TBI concussion, that sort of falls apart. It's almost like I'm paying attention to this light here that's shining on my eye that's really bothering me. [laughs] So I get distracted instead of talking to you, for example. Or those signals that I used to be able to block off, now I'm paying attention to it. So that mechanism causes the person to change their behavior and thinking. They can't complete the task.
Posted on BrainLine September 10, 2013.

Produced by Victoria Tilney McDonough, Lara Collins, and Ashley Gilleland, BrainLine.