Neurochemical and physiological mechanisms of executive control in healthy males

The effect of methylphenidate, atomoxetine and citalopram versus placebo on behavioural and physiological indices of executive control in healthy individuals.

Status

Completed

Phases

Phase 4

Study type

Interventional

Source

ANZCTR

Registry ID

ACTRN12609000625279

Enrollment

Registered

2009-07-27

Start date

2009-07-22

Completion date

Unknown

Last updated

2020-01-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

None listed

Brief summary

The purpose of this study is to determine how three different medications influence brain activity whilst healthy participants are performing cognitive tasks. The three medications are methylphenidate, atomoxetine and citalopram. The first two medications are commonly used to treat attention deficit hyperactivity disorder (ADHD) in both children and adults, whereas citalopram is used to treat depression in adults. Importantly, we know that these medications act on different chemical systems in the brain. What we do not know, however, is whether these medications can influence underlying brain activity when people are performing cognitive tasks. This project will help us to understand which chemicals in the brain modulate our ability as humans to inhibit and control our behaviour. Studying these effects in healthy people will provide important clues to the underlying biology of a range of mental disorders where problems of inhibition and control of behaviour are common.

Interventions

Methylphenidate (30mg), atomoxetine (60mg), citalopram (30mg). All administered as capsules. Participants will be tested over four sessions, administered one dose of one drug (or placebo) each session. Sessions are a minimum of one week apart to allow wash-out of drug. This study implements a cross-over design, with each participant receiving each of the three drugs and placebo over four sessions (one drug or placebo per session).

Study design

Allocation

Randomised controlled trial

Intervention model

Crossover

Primary purpose

Treatment

Masking

Blinded (masking used)

Eligibility

Sex/Gender

Male

Age

18 Years to 45 Years

Healthy volunteers

Yes

Inclusion criteria

Male, right-handed, Caucasian, non-smoker, normal or corrected-to-normal vision

Exclusion criteria

Smoker, abnormal vision, history of drug abuse, current recreational drug use, head injury resulting in unconsciousness, history of depression, history of anxiety, history of ADHD, history of psychosis, currently on other medication.

Outcome results