Post-traumatic stress disorder (PTSD) has always been associated with mental health, but new research suggests there's a physical aspect to it too – that a certain area of the brain is larger in people suffering from PTSD. Show That means we could improve the way we detect and treat the debilitating condition by looking at physical as well as psychological signs, giving doctors something outside the mind that they can study. The research focussed on the left and right amygdalae, those parts of the brain that control our fearfulness and how we respond to outside stimuli that could be seen as threatening or dangerous. The amygdalae also have a big role to play in the way we make decisions and process memories. "Many consider PTSD to be a psychological disorder, but our study found a key physical difference in the brains of military-trained individuals with brain injury and PTSD, specifically the size of the right amygdala," says one of the team, Joel Pieper from the University of California, San Diego. "These findings have the potential to change the way we approach PTSD diagnosis and treatment." The team scanned the brains of 89 current or former members of the military with mild traumatic brain injury, with 29 of those also diagnosed as having significant PTSD as well. When the researchers looked at those 29, they found their amygdalae were about 6 percent larger – particularly on the right side – compared with the participants who weren't affected by PTSD. No major differences in age, education, or gender were found between those with PTSD and those without. "We wonder if amygdala size could be used to screen who is most at risk to develop PTSD symptoms after a mild traumatic brain injury," says Pieper. "On the other hand, if there are environmental or psychological cues that lead to brain changes and enlargement of the amygdalae, then maybe such influences can be monitored and treated." Before we get ahead of ourselves, the researchers note that more research is needed into the relationship between PTSD and amygdala size: the research only shows association and doesn't prove that PTSD causes changes to the amygdalae. What's more, the brain injuries of most participants in this study were caused by blast injuries, so different injury types – such as those caused by sports concussions – may have different effects on the brain. Even with those limitations though, the researchers describe what they've found as an "intriguing structure-function relationship", especially considering the links between fear and memory and the amygdalae. The research follows a 2016 study that found some limited evidence of a link between PTSD and damage to brain tissue in blast victims, suggesting there might be other physical after-effects that go hand-in-hand with PTSD. Around 7.7 million people over the age of 18 are believed to suffer from PTSD in the US, and it can develop from any type of traumatic episode, from witnessing a natural disaster to serving on the front line. Let's hope scientists can figure out better treatments for the condition as the physical aspects of PTSD are more fully understood. The findings have yet to be published in a peer-reviewed journal, but have been presented at the American Academy of Neurology's Sports Concussion Conference. Researchers may have found a way to improve a common treatment for post-traumatic stress disorder (PTSD) by changing how the brain learns to respond less severely to fearful conditions, according to research published in Journal of Neuroscience. The study by researchers at The University of Texas at Austin Dell Medical School suggests a potential improvement to exposure therapy -- the current gold standard for PTSD treatment and anxiety reduction -- which helps people gradually approach their trauma-related memories and feelings by confronting those memories in a safe setting, away from actual threat. In a study of 46 healthy adults, researchers compared participants' emotional reactions to replacing an unpleasant electric shock on the wrist with a surprise neutral tone, instead of simply turning off the shocks. Omitting the feared shocks is the current norm in exposure therapy. The participants' brain activity was measured by functional magnetic resonance imaging (fMRI). Their emotional reactions were measured by how much they were sweating from their hands. Compared with simply turning off the shocks, replacing the feared shocks with a neutral tone was associated with stronger activity in the ventromedial prefrontal cortex -- an area critical for learning safety and inhibiting fear. Replacing the feared shock with a simple tone also lowered participants' emotional reactions to pictures that previously had been associated with the electric shock when participants were tested the next day. "This simple treatment of replacing an expected threat with an innocuous sound resulted in a long-lasting memory of safety, which suggests that the brain may be able to better control its fear response by means of a pretty straightforward, nonpharmaceutical intervention," says lead study author Joseph Dunsmoor, Ph.D., an assistant professor in the Department of Psychiatry at Dell Medical School. In the study, Dunsmoor's team randomly divided participants to two groups -- those who had the shock turned off and those who had the shock replaced by a neutral tone. Both groups were exposed to a picture of a face paired with an electric shock on the wrist on day one of the study. The groups were then exposed to the pictures with the shock turned off, or with the shock replaced by the surprising tone. Both groups returned the next day to measure brain activity and emotional reactions to the fear-conditioned pictures. The researchers measured participants' brain activity to the fear-conditioned pictures using fMRI scans. They also measured participants' emotional responses to the threat of receiving an electric shock based on the amount of sweat recorded from a hand. "It is well known that the brain learns by surprise," says Dunsmoor. "Our study suggests that replacing expected aversive events with neutral and unexpected events, even a simple tone, is one way to capture attention so that the brain can learn to regulate fear more effectively." What does research say about PTSD?It is a debilitating condition that affects an estimated one in 11 people at some time in their lives. Research shows that individuals diagnosed with PTSD have less access to treatment than individuals diagnosed with other mental health conditions, such as depression.
What does psychology say about PTSD?People with PTSD have intense, disturbing thoughts and feelings related to their experience that last long after the traumatic event has ended. They may relive the event through flashbacks or nightmares; they may feel sadness, fear or anger; and they may feel detached or estranged from other people.
What is the science or research behind PTSD?Someone who has PTSD or C-PTSD often has excessive activity in their amygdala, which can be picked up on brain scans. This is when the amygdala is too sensitive, triggers too easily or stays on high alert for longer than it should.
What theoretical perspective is PTSD?PTSD Theoretical Model
Dysfunctional hyperarousal is suggested to be the overriding feature of PTSD, and its independence of particular emotions is consistent with the diversity of peritraumatic emotions reported earlier.
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