The Effect of 5-hydroxytryptophan on ADHD Traits and Eye Movements

The aim of this project is to look at the impact of 5-Hydroxytryptophan (5-HTP) on distractibility. 5-HTP is the precursor to the neurotransmitter serotonin and is a chemical that the body produces naturally. There is evidence that distractibility is associated with a decreased level of serotonin. This research aims to see if giving people 5-HTP will alter their distractibility, which will form part of an initial assessment as to whether 5-HTP could be used to support people with attention problems. The study involves completing a short survey about mental health and behaviours, and if eligible, participation in an in-person study at the University of Sheffield. The in-person session involves completing some cognitive tasks to look at eye movement, taking 5-HTP or a sugar tablet with no active ingredients, and then completing the tasks again after a 90-minute wait.

Inclusion Criteria: * 18-65 years of age * Normal or corrected to normal vision with contact lenses. * Score of \14 on the ASRS v5 (assessed in pre screen questionnaire) Exclusion Criteria: * Current use of psychostimulant medication or medication for the treatment of ADHD * Current use of medications known to impact the serotonergic system (e.g., SSRIs). * Smoking or vaping * Pregnancy * Breast feeding * Lactose intolerance * Veganism * Dyslexia