Skip to content

Examining the effects of serotonin on perceptual awareness and attention.

In healthy adults, how do buspirone and citalopram compared with placebo effect switch rate in perceptual rivalry?

Status
Recruiting
Phases
Phase 4
Study type
Interventional
Source
ANZCTR
Registry ID
ACTRN12611000084987
Enrollment
20
Registered
2011-01-24
Start date
2011-03-01
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

Binocular rivalry occurs when different stimuli are presented to the left and right eye simultaneously. Under these conditions the observer will consciously perceive only one of the two images at a time, with the respective dominance of the two images alternating every few seconds. A similar phenomenon is also observed in hearing. Previous studies have shown that the rate of alternation is affected by certain medications that affect the serotonin system. We will administer two such medications to healthy individuals to further investigate how the serotonin system is involved in perceptual rivalry. The main implications of this study relate to pure research and understanding the neural mechanisms underlying perception. There is currently no clinical aim for this study.

Interventions

Oral tablets of Buspirone (15mg), Citalopram (20mg) or placebo will be administered to healthy adults. Each participant will participate in 4 separate sessions of testing separated by at least 2 weeks: session1/Placebo + Buspirone (2.5 hours later), session2/ Citalopram + Buspirone (2.5 hours later), session3/ Placebo + Placebo (2.5 hours later), session4/ Citalopram + Placebo (2.5 hours later). The study will investigate the neurochemical basis of binocular rivalry, a phenomenon that is a featu

Oral tablets of Buspirone (15mg), Citalopram (20mg) or placebo will be administered to healthy adults. Each participant will participate in 4 separate sessions of testing separated by at least 2 weeks: session1/Placebo + Buspirone (2.5 hours later), session2/ Citalopram + Buspirone (2.5 hours later), session3/ Placebo + Placebo (2.5 hours later), session4/ Citalopram + Placebo (2.5 hours later). The study will investigate the neurochemical basis of binocular rivalry, a phenomenon that is a feature of normal vision. No abnormal condition or disease is being investigated as part of this study. The medications in this study are already approved by the Australian Therapeutic Goods Administration.

Sponsors

The University of Melbourne
Lead SponsorUniversity

Study design

Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Diagnosis
Masking
Blinded (masking used)

Eligibility

Sex/Gender
All
Age
18 Years to 50 Years
Healthy volunteers
Yes

Inclusion criteria

Healthy adults

Exclusion criteria

Previous personal or first-degree family history of psychiatric or neurological disorders or suicidality, impairements in vision or audition, hepatic or cardiac function (including diagnosed hypertension), pregnancy or breastfeeding, previous intolerance or hypersensitivity to buspirone, citalopram or related medications, current or recent (last 2 weeks) use of psychotropic medication, psychoactive substances or any other medications known to interact with buspirone or citalopram. Participants will also be excluded if their blood pressure is found to be above 140/100 and remains above this level for fifteen minutes.

Outcome results

None listed

Source: ANZCTR · Data processed: Feb 4, 2026