CBT and the Neural Circuits of Anxiety

This study will aim to test whether specific neural circuitry changes, proposed on the basis of a neurocognitive model of anxiety, are a mechanism of action for Cognitive Behavioural Therapy (CBT) interventions. This study aims to provide a theoretical model of the neurobiological mechanisms of CBT's therapeutic effect, where there currently is none, and potentially allow for more targeted/specific approaches to anxiety disorders following the identification of key CBT mechanisms. The ultimate aim is to improve the efficacy of CBT, and more generally, psychological interventions for anxiety disorders.

To test the hypothesis that the neural circuitry of the amygdala and prefrontal cortex will respond to CBT, the impact of a course of CBT on cortical-subcortical circuitry will be tested via a case-control study in individuals entering Improving Access to Psychological Therapies (IAPT) services (IAPT step 3; i.e., full CBT) for anxiety disorders and individuals in waiting lists. This design leverages the naturalistic waiting times in the clinical service and does not interfere with treatment as usual. Measures of brain region-specific connectivity and emotion-related behavioural performance will be assessed through testing sessions at the University College London (UCL) Institute of Cognitive Neuroscience and the Birkbeck-UCL Centre for NeuroImaging (BUCNI), involving computerised cognitive/psychological tasks and functional magnetic resonance imaging (fMRI). The aims are to: 1. test whether this circuit responds to a course of CBT, by demonstrating disengagement of the circuit following CBT 2. relate this change in circuit function to behaviour through cognitive measures of emotional processing 3. explore the neurobiological features that distinguish patients who respond to CBT and those who do not 4. compare the data from this study to another on-going study assessing the impact of pharmacological interventions for anxiety, allowing for the comparison of neurobiological mechanisms of psychological vs. pharmacological treatments in anxiety.