Ketamine Use Disorder: Exploring Psychological and Neurological Mechanisms. MRC GW4 BioMed DTP PhD studentship for 2026/27 Entry, Department of Psychology. Ref: 5634

Supervisors

Lead Supervisor: Professor Celia Morgan - University of Exeter - Department of Psychology

Co-Supervisors:

Professor Tom Freeman - University of Bath - Department of Psychology

Dr Anjali Bhat - University of Exeter - Department of Psychology

The GW4 BioMed2 MRC DTP is offering up to 17 funded studentships across a range of biomedical disciplines, with a start date of October 2026.

These four-year studentships provide funding for fees and stipend at the rate set by the UK Research Councils, as well as other research training and support costs, and are available to UK and International students.

About the GW4 BioMed2 Doctoral Training Partnership

The partnership brings together the Universities of Bath, Bristol, Cardiff (lead) and Exeter to develop the next generation of biomedical researchers. Students will have access to the combined research strengths, training expertise and resources of the four research-intensive universities, with opportunities to participate in interdisciplinary and 'team science'. The DTP already has over 90 studentships over 6 cohorts in its first phase, along with 80 students over 4 cohorts in its second phase.

The 122 projects available for application, are aligned to the following themes;

• Infection, Immunity, Antimicrobial Resistance and Repair

• Neuroscience and Mental Health

• Population Health Sciences

Applications open on 1 September 2025 and close at 5.00pm on 20th October 2025.

Please note that we may close the application process before the stated deadline if an unprecedented number of applications are received– check our website for details.

Studentships will be 4 years full time. Part time study may also be available.

Project Information

Research Theme:  Neuroscience & Mental Health

Summary:

Ketamine use disorder is the fastest growing addiction in the UK, with ~ 300% increase in people seeking treatment over the past year. This project explores the psychological and neurobiological determinants of ketamine use disorder. Working closely with local drug services, the PhD student will use a variety of techniques including acute drug challenge, neuroimaging, cognitive testing and interviews to develop a rich understanding of the causes and consequences of ketamine use disorder. Through this we hope to inform treatment of this sometimes life threatening, and frequently misunderstood, health condition. 

Description:

Ketamine is a dissociative anaesthetic that has been established as a rapid acting antidepressant in treatment resistant depression (e.g. Morgan et al., 2014). The past two decades have simultaneously seen a surge in recreational ketamine consumption, such that ketamine has become the fourth most commonly used drug in clubbing environments in the United Kingdom (UK) (ONS, 2024), with a threefold increase among individuals under 25 years old (ONS, 2024). Concurrently, the number of adults requiring treatment for ketamine use disorder (KUD) has risen fivefold since 2015 (Home Office UK, 2024). Despite the growing prevalence and associated burden on healthcare services still relatively little is known about KUD, which often has serious physical health complications including ketamine-induced ulcerative cystits. Our group has recently published the largest study of ketamine users (Harding et al. 2025) which has identified significant gaps in knowledge concerning KUD, particularly in the extent of its addictive potential and effective treatment strategies.

Studies in animals (Jiang et al.2024) and humans (Williams et al. 2019) have demonstrated that ketamine’s antidepressant and anti-suicidal effects are at least partly dependent on the opioid system. Recent work has proposed that bifunctional, synergistic interactions between n- methyl d aspartate (NMDAR) and mu opioid receptor (MOR) underlie its mechanism of action in depression (Levinstein et al. 2025 ). Additional findings further support an opioid component in ketamine’s mechanism: its analgesic effects are MOR-dependent (Panckeo et al. 2014), and even at subanaesthetic doses, ketamine achieves sufficient MOR occupancy to trigger downstream signalling (Bonaventura et al. 2021). Elevation of β- endorphin levels following ketamine administration (Jiang et al. 2024), along with the attenuation of ketamine's effects by opioid antagonists, further supports the involvement of opioid system activation in its pharmacological action. Collectively, these findings provide a compelling rationale for exploring the role of the mu opioid receptor action in ketamine addiction.

The key research question of this thesis will examine the impact modulating mu opioid receptor activity on the rewarding effects of ketamine and addictive properties of ketamine in ketamine users (Harding et al. 2025).

Objectives the student will address:

Proposed Study 1) Understanding the lived experience of ketamine addiction.

The student will co-create with our lived experience representatives an interview and survey of ketamine addiction to capture the key withdrawal symptoms and explore predictors of relapse and maintenance of addiction in ketamine users and then gather this data using links with local drug services in Bristol, Bath, Cardiff and Exeter. This will serve two functions: a) will inform understanding of ketamine use disorder b) this information will then be used to develop into experimental stimuli.

Proposed Study 2) Explore the impact of mu opioid modulation on acute response to ketamine in ketamine users.

The student will conduct an acute challenge study with ketamine and naltrexone in ketamine users exploring whether the modulation of mu opioid activity reduces rewarding effects of ketamine.

Proposed Study 3) Chronic Effects of mu opioid modulation in ketamine users.

This study will explore the impact of chronic dosing with naltrexone over 14 days on the experience of daily craving and reward sensitivity in people with ketamine use disorder. The end goal of this study would be to inform the development of treatment for ketamine use disorder.

Funding

This studentship is funded through GW4BioMed2 MRC Doctoral Training Partnership. It consists of UK tuition fees, as well as a Doctoral Stipend matching UK Research Council National Minimum (£20,780 p.a. for 2025/26, updated each year).

Additional research training and support funding of up to £5,000 per annum is also available.

Eligibility

Residency:

The GW4 BioMed2 MRC DTP studentships are available to UK and International applicants. Following Brexit, the UKRI now classifies EU students as international unless they have rights under the EU Settlement Scheme. The GW4 partners have agreed to cover the difference in costs between home and international tuition fees. This means that international candidates will not be expected to cover this cost and will be fully funded but need to be aware that they will be required to cover the cost of their student visa, healthcare surcharge and other costs of moving to the UK to do a PhD.  All studentships will be competitively awarded and there is a limit to the number of International students that we can accept into our programme (up to 30% cap across our partners per annum).

Academic criteria:

Applicants for a studentship must have obtained, or be about to obtain, a first or upper second-class UK honours degree, or the equivalent qualification gained outside the UK, in an appropriate area of medical sciences, computing, mathematics or the physical sciences.  Applicants with a lower second class will only be considered if they also have a Master’s degree. Please check the entry requirements of the home institution for each project of interest before completing an application. Academic qualifications are considered alongside significant relevant non-academic experience.

English requirements:

If English is not your first language you will need to meet the English language requirements for the University of Exeter by the start of the programme. Please refer to the details in the following web page for further information https://www.exeter.ac.uk/study/englishlanguagerequirements/

Please check the relevant English Language requirements of the university that will host the PhD project.  

Data Protection

If you are applying for a place on a collaborative programme of doctoral training provided by Cardiff University and other universities, research organisations and/or partners please be aware that your personal data will be used and disclosed for the purposes set out below.

Your personal data will always be processed in accordance with the General Data Protection Regulations of 2018. Cardiff University (“University”) will remain a data controller for the personal data it holds, and other universities, research organisations and/or partners (“HEIs”) may also become data controllers for the relevant personal data they receive as a result of their participation in the collaborative programme of doctoral training (“Programme”).

Further Information

For an overview of the MRC GW4 BioMed programme please see the website www.gw4biomed.ac.uk

Entry requirements

Academic Requirements

Applicants for a studentship must have obtained, or be about to obtain, a first or upper second-class UK honours degree, or the equivalent qualification gained outside the UK, in an appropriate area of medical sciences, computing, mathematics or the physical sciences. Applicants with a lower second class will only be considered if they also have a Master’s degree. Please check the entry requirements of the home institution for each project of interest before completing an application. Academic qualifications are considered alongside significant relevant non-academic experience.

English Language Requirements

If English is not your first language you will need to meet the English language requirements for the University of Exeter by the start of the programme. Please refer to the relevant university website for further information.  This will be at least 6.5 in IELTS or an acceptable equivalent.  Please refer to the English Language requirements web page for further information.

Please check the relevant English Language requirements of the university that will host the PhD project. 

How to apply

A list of all the projects and how to apply is available on the DTP’s website at gw4biomed.ac.uk.  You may apply for up to 2 projects and submit one application per candidate only.

Please complete an application to the GW4 BioMed2 MRC DTP for an ‘offer of funding’.  If successful, you will also need to make an application for an 'offer to study' to your chosen institution.

Please complete the online application form linked from our website by 5.00pm on Monday, 20th October 2025.  Please note that we may close the application process before the stated deadline if an unprecedented number of applications are received– check the DTP’s website for details and updates

If you are shortlisted for interview, you will be notified from Tuesday, 23rd December 2025.  Interviews will be held virtually on 27th and 28th January 2026.  

Further Information

For informal enquiries, please contact GW4BioMed@cardiff.ac.uk

For project related queries, please contact the respective supervisors listed on the project descriptions on our website.

Summary