The impact of Sulpiride (600mg; a dopamine antagonist) on behavioural and electrophysiological measures of visuospatial attention and inhibition

A DAT1 genotype and DRD2 Taq1A genotype, placebo controlled, randomised, double blind, crossover designed study of the effect of Sulpiride (600mg) on visuospatial attention and cognitive control measures (recorded with electroencephalography (EEG) and behavioural tasks) in a sample of 50 healthy adults

Status

Recruiting

Phases

Phase 1

Study type

Interventional

Source

ANZCTR

Registry ID

ACTRN12617000652370

Enrollment

Registered

2017-05-05

Start date

2016-11-11

Completion date

2018-11-30

Last updated

2018-06-11

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

Conditions

None listed

Brief summary

This study will investigate whether temporarily reducing dopamine transmission in the healthy brain affects an individual’s spatial selective attention, that is, the direction in space (left or right) in which an individual’s visual attention naturally falls. By combining this investigation with measures of electrical activity in the brain and genetic testing, we hope to gain a deeper understanding of the mechanisms involved in spatial attention and the influence on these mechanisms of genes implicated in the structure and function of the dopamine system in the brain. Uncovering the mechanisms of spatial attention may help us better understand and treat disorders involving spatial attention deficits, including Attention Deficit Hyperactivity Disorder, which involves an impaired awareness of, and ability to respond to, objects and information in a particular area of visual space.

Interventions

Participants will attend 2 separate sessions, one week apart (on the same day and time). On each occasion, the participant will be given a capsule to swallow containing either 600mg sulpiride or a placebo sugar pill, according to a randomised, double blind procedure. Participants will commence the study tasks after 180 minutes have elapse (to coincide with peak drug levels) and will complete the tasks within 330 minutes. Observation will occur for a further 30 minutes.

Study design

Allocation

Randomised controlled trial

Intervention model

Crossover

Primary purpose

Treatment

Masking

Blinded (masking used) (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender

All

Age

18 Years to 45 Years

Healthy volunteers

Yes

Inclusion criteria

Inclusion Criteria: Participants must be right handed, aged between 18 and 45, caucasian (all four grandparents of European descent) and neurologically healthy. Females must not be pregnant or breastfeeding and must be taking the combined progesterone/oestrogen oral contraceptive pill.

Exclusion criteria

Participants are ineligible for the study if any of the following apply: current smokers or have smoked more than 5 cigarettes a week in their lifetime; alcohol dependence; any current or history of neurological or psychiatric illness; any current or history of psychotropic drug use; illicit drug use in the last 6 months; any history of significant illicit drug use or more than monthly cannabis use, pregnant or breastfeeding.

Outcome results