Formal thought disorder is a highly disabling experience affecting between 27-50% of those diagnosed with a schizophrenia-spectrum disorder (psychosis). It is often characterised by tangential speech, loose associations, incoherence and illogicality making dialogue challenging for speaker and listener. It has a profound impact upon an individual’s ability to communicate and express themselves – to show their understanding and to be understood. This may undermine their autonomy, prevent their meaningful involvement in treatment decisions and contribute to ‘epistemic injustice’ whereby a person is assumed to be unable to engage in a whole range of epistemic practices, including knowing, reasoning and sharing knowledge.

More severe thought disorder is associated with greater subjective distress, emotional arousal, more frequent hospital admissions, increased risk of unemployment, and reduced occupational and social functioning. Despite this severe impact, there have been no randomised controlled trials of psychological interventions designed specifically to treat it.

By improving our understanding of what causes and maintains thought disorder in psychosis, the work in this PhD will contribute towards a longer-term programme of research which aims to develop and test a safe and effective psychological intervention for it. The PhD will be undertaken with the support of a collaborative supervisory team from Edinburgh Napier University and NHS Grampian with extensive experience in academic and clinical research. The research has three phases making use of different research methodologies and including diverse research populations to bring together evidence to create a psychological model of thought disorder.

Firstly, the student will undertake a systematic review of the literature to enhance our understanding of the current evidence in a specific area of research relevant to thought disorder. The second phase will involve a series of qualitative interviews conducted by the student in two populations. Patients with a diagnosis of schizophrenia-spectrum disorder at different stages of their recovery will be interviewed to understand their experiences and beliefs about what may have caused, maintained, and improved their thought disorder. Clinical staff who have experience of working with thought disorder will be interviewed to gain an understanding of their clinical approaches to communicating with individuals and any strategies they use to overcome difficulties with this. They will also be asked for their thoughts on causes, maintenance factors, and potentially important psychological mechanisms which could be targets for intervention.

The student will then collect a large dataset using an online survey design, measuring variables which are potentially relevant to the development and maintenance of thought disorder. Data will be used to construct a hypothetical model of subclinical thought disorder using network analysis and structural equation modelling. Data acquisition is likely to involve novel AI-led data collection techniques to capture and assess subclinical thought disorder markers in the speech patterns of participants.

The evidence gathered throughout this PhD, and the final hypothetical model will make an essential contribution toward the longer-term intervention development programme. Work undertaken across the studies will equip the student with a comprehensive range of research and critical appraisal skills, along with experience of recruitment and assessment in clinical and non-clinical settings. In addition to this an applied research placement will be offered during the PhD to further enhance the candidate’s skill set whether they aspire to a future career in research, academia or clinical practice.