The neurobiology of attention, avoidance and self-appraisal - Study 2

Background

This REP study is a screening assessment for an MRI study of which the theoretical background is given below; Repetitive negative thinking, avoidance behaviours, and attentional biases are common features in mood and anxiety disorders. These traits interfere with the success of cognitive-behavioural therapy (CBT), an effective evidence-based treatment for these disorders. This project will identify the brain mechanisms underlying these clinical features using functional magnetic resonance imaging (MRI) and will examine how brain-derived measures relate to treatment response.

Research Questions / Hypotheses

This study is a phone assessment that is used to screen participants for an MRI project. The survey responses of the eligible participants who completed this study (and study 1) used as a part the data for the main project (if they consented to take part in the main study after completing this study and the study 1). Research questions for the main study; What are the distinct neural circuits responsible for the process of repetitive negative thinking, avoidance behaviours and attentional biases? Can measures of brain activity can help clinicians predict treatment outcomes for individual patients?

Participants

Our exclusion criteria is ;Being based in Melbourne, Aged 18 to 40, Have no major hearing impairment, Understand and speak English sufficiently to complete a phone interview and follow instructions during an MRI session, Have no serious mental illness (e.g., psychosis). For this study, we only contacted the people are be eligible ( based on study 1 responses), therefore we did not exclude any participants. These participants were signed up and assigned their REP credits by us upon consenting to the study. We had 31 participants in total for this study.

Methods

Psychological assessment over the phone (using MINI-7 or DIAMOND) In the main study; Participants will take part in a single testing session. After providing consent, participants will be asked to provide two saliva samples (one for the salivary measurement of sex and stress hormones, and one for testing genetic variants/genotyping). The provision of saliva samples will be optional for all participants and will take between 5 and 10 minutes. Prior to MRI scanning, control participants will complete a short assessment battery of demographic and psychological questionnaires, as well as the Mini-International Neuropsychiatric Interview (M.I.N.I.). This pre-MRI task training will take approximately 60 min to complete. All participants will then undergo brain MRI during a session that will last approximately 60min. The scanning session will involve the Research Ethics and Integrity acquisition of a standard anatomical MRI (10min) and resting state fMRI scans (<10min), after which they will complete the Challenging Negative Beliefs Task (~10min), the Attention Network Task (~8min) and the Active Avoidance Task (~10min) during scanning. The tasks will be displayed on a MRI-compatible screen and participants responses will be provided 2-button control pad.

Results

General analyses methods in the main study; Imaging data will be transferred and processed on a Mac OS platform running MATLAB (The MathWorks Inc.,Natwick, USA) where pre-processing will be performed using Statistical Parametric Mapping (SPM) software (Wellcome Trust Centre for Neuroimaging, UK). Single subject analysis Each participant’s pre-processed time-series will be input into SPM first-level general linear model (GLM) analyses. A model will be created that specifies the onsets of each event-type (convolved with canonical hemodynamic response function) for all task phases. Certain tasks (e.g., ANT) will be analysed as a combination of block and event-based activities. Group level analysis Activation analyses using the SPM GLM framework will be performed. There will also be correlational analyses,where BOLD signal responses to tasks are correlated with participants’ self-report scores and response to treatment in order to investigate individual differences. Multiple comparisons correction will be undertaken to ensure overall p<0.05. Associations between treatment response variables and brain-derived measures Linear mixed-effect models will be used to identify how functional activation and connectivity effects predict response to treatment in the clinical group. These effects will be run using psychopathology severity scores as a repeated-measure–dependent variable; a random effect for participant; and fixed effects for age, sex, connectivity effects between brain regions and the interaction between time and connectivity levels. The main effect of time will indicate the slope of psychopathology severity changes from admission to treatment at the Psychology Clinic to posttreatment. The study is still ongoing.

Implications

The main study will highlight important factors that have thus far been minimally studied in neuroscience. This will be particularly relevant to how avoidance, repetitive negative thinking, and attention are conceptualized in the brain and how brain-derived measures relate to treatment outcome. It therefore has the capacity to be completely novel as well as providing insights that could have a marked impact on clinical research and treatment. Results will be made available in refereed journal articles and in conference presentations and/or posters.