Cognitive behavioral therapy changes brain activity in anxious children, study finds

Researchers at the National Institutes of Health have found overactivation of many brain regions, including the frontal and parietal lobes and the amygdala, in unmedicated children with anxiety disorders. They also showed that treatment with cognitive behavioral therapy (CBT) led to improvements in clinical symptoms and brain function.

The findings shed light on the brain mechanisms underlying the acute effects of CBT to treat one of the most common mental disorders. The study, published in the American Journal of Psychiatrywas led by researchers at NIH’s National Institute of Mental Health (NIMH).

“We know that CBT is effective. These findings help us understand how CBT works, a critical first step in improving clinical outcomes,” said lead author Melissa Brotman, Ph.D., head of the Neurosciences and Novel Therapies Unit at NIMH Intramural. Research program.

The study included 69 unmedicated children diagnosed with an anxiety disorder who underwent 12 weeks of CBT according to an established protocol. CBT, which involves modifying dysfunctional thoughts and behaviors through gradual exposure to anxiety-provoking stimuli, is currently the gold standard for treating anxiety disorders in children.

Researchers used clinician-rated measures to examine changes in children’s anxiety symptoms and clinical functioning from pre- to post-treatment. They also used task-based fMRI to examine changes in the whole brain before and after treatment and compared them to the brain activity of 62 children of the same age without anxiety.

Anxious children showed greater activity in many brain regions, including cortical areas in the frontal and parietal lobes, which are important for cognitive and regulatory functions, such as attention and emotion regulation. The researchers also observed elevated activity in deeper limbic areas like the amygdala, which are key to generating strong emotions, such as anxiety and fear.

After three months of CBT treatment, anxious children showed a clinically significant decrease in their anxiety symptoms and improvement in functioning. The increased activation observed before treatment in many frontal and parietal brain regions also improved after CBT, falling to levels equal to or lower than those of non-anxious children. According to the researchers, reduced activation of these brain areas may reflect more effective engagement of cognitive control networks after CBT.

However, eight brain regions, including the right amygdala, continued to show higher activity in anxious children than in non-anxious children after treatment. This persistent pattern of increased activation suggests that certain brain regions, particularly limbic areas that modulate responses to anxiety-inducing stimuli, may be less sensitive to the acute effects of CBT. Altering activity in these regions may require longer duration of CBT, additional forms of treatment, or direct targeting of subcortical brain areas.

“Understanding the brain circuits that underlie feelings of severe anxiety and determining which circuits normalize and which do not as anxiety symptoms improve with CBT is essential to advancing treatment and make it more effective for all children,” said first author Simone Haller, Ph.D., director of research and analysis in the NIMH Neurosciences and Novel Therapeutics Unit.

In this study, all anxious children received CBT. For comparison, the researchers also measured the brain activity of a separate sample of 87 young people at high risk for anxiety due to their childhood temperament (e.g., showing high sensitivity to new situations). Because these children had not been diagnosed with an anxiety disorder, they did not receive CBT treatment. Their brain scans were taken at ages 10 and 13.

In adolescents at risk for temperamental anxiety, higher brain activity was linked to increased anxiety symptoms over time and matched brain activity seen in children diagnosed with an anxiety disorder before treatment. This provides preliminary evidence that brain changes in anxious children were induced by CBT and may be a reliable neural marker of anxiety processing.

Anxiety disorders are common among children and can cause significant distress in social and academic situations. They are also chronic, with a strong link to adulthood, when they become more difficult to treat. Despite the effectiveness of CBT, many children continue to experience symptoms of anxiety after treatment. Improving therapy to more effectively treat childhood anxiety can have short- and long-term benefits and prevent more serious problems later in life.

This study provides evidence, in a large group of untreated youth with anxiety disorders, of altered brain circuits that underlie the effects of CBT treatment. The results could ultimately be used to improve treatment outcomes by targeting brain circuits linked to clinical improvement. This is particularly important for the subset of children who did not improve significantly after short-term CBT.

“The next step in this research is to understand which children are most likely to respond. Are there factors we can assess before treatment begins in order to make the most informed decisions about who should receive what treatment and When? Answering these questions would further translate our research findings into clinical practice,” Brotman said.