Looking into the eye of ADHD.

The study design consists of three phases, (1) exploring eye functioning in ADHD and healthy controls, (2) an explorative single-dose intervention of treatments commonly used in adults with ADHD on eye functioning, and (3) an effect evaluation of a 3-week treatment period of these commonly used treatments on eye functioning. This trial registration number only incorporates phase 3 of the project.



In Phase 3, ADHD patients that have participated in Phase 1 will be randomized for any of the interventions or for a placebo condition (as a control condition for Mph and Mel) or for a waiting list group (as a control condition for LT). Participants that have already participated in Phase 2, with major substance abuse, or any contra-indication for the interventions will be excluded. Each group will have n=10 participants per group, or, if the Phase 2 results indicate so, larger groups will be determined. All conditions and medication intake schedules are designed according usual treatment regimes:



1A) Mph, 3 x 20 mg/day at 8 AM, 12 PM and 4 PM during 3 weeks, n=10

1B) Placebo, 3 x 20mg/day at 8 AM, 12 PM and 4 PM during 3 weeks, n=10

2A) LT, 30 minutes/day in the morning during 3 weeks, n=10

2B) Waiting list during 3 weeks, n=10

3A) Mel, 3 mg/day in the evening 1 h before desired bedtime during 3 weeks, n=10

3B) Placebo, 3 mg/day in the evening 1 h before desired bedtime during 3 weeks, n=10



At baseline and ffter the 3-week intervention period, an eye functioning assessment battery will be assessed. The intra-individual change of the outcomes between the baseline and the Phase 3 measurements will be compared between the Mph and the placebo group, between the LT and waiting list group, and between the Mel and Placebo group. The correlation between the PIPR or any other eye functioning measure and the effect of the intervention on ADHD symptoms or circadian rhythm will be investigated. Any comorbidity, self-reported oversensitivity to light, and minor substance abuse will be analyzed as covariates in regression models when evaluating the effect of the interventions on the eye functioning improvement.

An intervention with Methylphenidate, Melatonin or Light Therapy will lead to changes in visual functioning.

The assessments will take place at baseline and immediately after the 3-week intervention period.

A 3-week intervention of one of the following:



1A) Methylphenidate, 3 x 20 mg/day

1B) Placebo, 3 x 20mg/day




2A) Light Therapy, 30 minutes/day

2B) Waiting list




3A) Mel, 3 mg/day

3B) Placebo, 3 mg/day