Childhood trauma associated with altered fear learning: A possible pathway to PTSD

A recent study published in Psychiatric medicine suggests that childhood trauma may alter the way children learn to respond to fear, which may contribute to the development of post-traumatic stress disorder (PTSD) later in life of youth. The researchers found that the children who had been exposed to trauma showed higher physiological responses to the fearful trauma during the learning task. This higher response, in turn, was associated with an increase in PTSD symptoms over time.

Unfortunately, childhood trauma is common, with nearly half of all children in the United States experiencing some form of trauma. Such experiences, including physical and sexual abuse, domestic violence and social violence, have been linked to a range of mental health problems, including depression, anxiety and PTSD . Because of the widespread impact of early trauma, researchers have been working to understand how these experiences contribute to the development of mental health issues, with the ultimate goal of developing measures to help prevent these problems.

“Previous work has shown that youth who have had very traumatic experiences (eg, abuse, experiences of violence) during childhood show differences in how they respond to fear processing, but there has been little agreement before that. these organizations,” said study author Laura Machlin, who conducted the research while a postdoctoral fellow at Harvard University.

“I was interested in using a large, longitudinal sample of children with multiple early life experiences, including traumatic experiences, to directly address if children with experiences related to ts’ In addition, I was interested in the changes in the way young people respond in traumatic events may be associated with greater risk of psychopathology symptoms over time.”

The study was based on a sample of 215 children between the ages of 10 and 13, who were all part of a larger longitudinal study. The researchers were particularly interested in children who had experienced various types of trauma, including both trauma (such as abuse or exposure to violence) and deprivation (such as neglect or lack of emotional support ). The goal was to determine how anxiety and depression are related to changes in fear learning and to track how these changes may be related to the development of mental health problems over time.

At the beginning of the study, the children and their parents completed questionnaires and interviews about the children’s experiences of trauma and deprivation, as well as their mental health symptoms. A few weeks later, the children participated in a fear conditioning task, a widely used cognitive test designed to measure how well participants learn to distinguish between fearful and non-fearful objects.

In this task, children were exposed to two different cues: one that was repeatedly followed by an unpleasant stimulus (eg, a mild startle or loud noise) and one that was not. The children’s physiological responses, particularly their skin conductance (a measure of sweat gland activity often used as a signal of fear or arousal), were recorded during the task.

Two years after the initial assessment, the children’s mental health symptoms were reassessed to see if their fear learning responses predicted any changes in symptoms. a PTSD, anxiety, or externalizing behavior (such as aggression or delinquency).

The results of the study provided important insight into the relationship between childhood trauma, fear learning, and mental health. The researchers found that children who had experienced greater trauma showed higher responses of skin conductance during the fear conditioning process. This means that these children were more active in following the stimuli they associate with danger, suggesting that they are more sensitive to potential threats. These elevated responses were not observed in children who had experienced deprivation without trauma, suggesting that trauma, in particular, was driving these changes in learning. fear.

The researchers also found that a higher fear response in these children was related to an increase in PTSD symptoms during the two-year follow-up. In other words, children who experienced more trauma and who showed a stronger physical response to fear were more likely to develop or worsen PTSD symptoms as they grew older.

Interestingly, the study did not find the same relationship between modified fear learning and other types of mental health issues, such as anxiety or externalizing behavior. This suggests that the changes in fear learning observed in traumatized children may be related specifically to PTSD rather than psychopathology in general.

“We found that adolescents with traumatic experiences can more easily distinguish between fearful stimuli and safe stimuli while learning less about these stimuli measured by differences of the skin conductance response, which is an indirect measure of the level of arousal caused by the stimulus,” Machlin told PsyPost. “This increase in arousal to new fearful stimuli was associated with greater PTSD symptoms over time in young adults with trauma-related experiences. Overall, the work This suggests that differences in the way youth learn about new traumatic events may be another mechanism by which childhood trauma-related experiences increase risk for PTSD symptoms in youth. ”

Although this study provides important new information, it also comes with several caveats. First, the sample was not clinical, meaning that although the children reported symptoms of PTSD and other mental health problems, they were not diagnosed with these conditions. Future research may benefit from looking at children diagnosed with PTSD to see if the findings hold true for a more severely affected population.

“This sample includes children taken from a long-term study who were 10 to 13 years old and is not a clinical sample diagnosed with a specific illness,” said Machlin. “This work needs to be done in a clinical model.”

Despite these limitations, the study provides important evidence that altered fear learning may be one way in which childhood trauma leads to the development of PTSD. This result can help identify interventions aimed at reducing stress-related problems in young people.

The study, “Changes in fear learning as a mechanism mediating childhood exposure to violence and PTSD symptoms: a longitudinal study,” was written by Laura Machlin, Margaret A. Sheridan, Lucy A. Lurie, Steven W. Kasparek , Stephanie Gyuri Kim, Matthew Peverill, John McClellan France, Madeline M. Robertson, Tanja Jovanovic, Liliana J. Lengua, and Katie A. McLaughlin.