Dr Will Lawn


I studied Natural Sciences (Experimental Psychology) at the University of Cambridge and then completed a PhD at University College London, supervised by Professor Val Curran and Professor Celia Morgan. My PhD examined reward processing perturbations in nicotine and cannabis addictions. I then worked as a post-doctoral research associate on the KARE clinical trial investigating ketamine as a treatment for alcohol dependence. I have also worked with Professor Adam Winstock on his Global Drug Survey data and with Dr Gill Bedi at Columbia University’s Psychiatric Institute in New York.

Current work

I currently work as a post-doctoral research associate at University College London, in the Clinical Psychopharmacology Unit. I am working on an MRC-funded project which examines whether adolescence represents a vulnerable period for cannabis-related harms. And if teenagers are at greater risk, in which psychological and neural domains does this additional harm manifest itself.

Areas of particular interest

My main interest, and research focus, is teenage cannabis dependence. I am also interested in the neural substrates of drug-related decision-making; theories of addiction; and the application of psychedelic drugs in treating addiction.

Future work

I would like to further investigate the reasons behind teenagers’ greater vulnerability to developing cannabis dependence compared to adults. I would also like to help improve treatment and prevention strategies for teenagers with cannabis use disorder.

cannTEEN: a longitudinal, MRI study investigating how cannabis differentially affects teenagers and adults

Presentation link: cannTEEN: a longitudinal, MRI study investigating how cannabis differentially affects teenagers and adults

Adolescence is a period in which the brain and mind continue to develop, and it is thought that the harms associated with cannabis may be greater during adolescence than in later years. Despite these concerns, studies directly comparing teenage and adult cannabis users are scarce.

I will describe a new longitudinal, magnetic resonance imaging (MRI) study of four groups, made up of teenagers (16-17 years) and adults (26-29 years) who do and don’t smoke cannabis (aim total n=272). The study is currently in progress (current n=183, March 2019). Participants attend five behavioural sessions over one year (one session every three months), when we measure cannabis addiction, mental health, cognitive functions and endo- and exogenous cannabinoid levels. A subsection of participants (n=140) attend an MRI session at the start and end of the year, when we record blood oxygen level dependent (BOLD) response associated with reward anticipation, working memory and response inhibition, alongside brain structure and white matter integrity.

The overall aim of the project is to determine whether teenage cannabis users show more adverse changes than adult cannabis users (in comparison to their non-using control groups) in mental health, cognitive and neural domains over one year.

By autumn 2019 we will have collected our baseline data for the whole sample. I will report initial, cross-sectional differences between our four groups on cannabis addiction, psychotic-like symptoms, and BOLD response associated with reward anticipation and response inhibition.

This research is funded by the Medical Research Council.