Influence of Oxytocin on Neurophysiological Responses to Live Faces

What Was Tested

In this phase 1, phase 2 trial, researchers set out to test Oxytocin.

On a behavioral level, participants tend to look shorter at live faces with a direct gaze as compared to averted gaze (Akechi et al., 2013).

It had two arms (groups): Oxytocin (experimental) and Placebo (placebo comparator).

The registry classes the interventions as drug.

More on the Plan

In this randomized, placebo controlled, double blinded study, the investigators will investigate whether oxytocin modulates the behavioral and neurophysiological responses elicited by direct gaze.

The investigators hypotheses that oxytocin attenuates the heightened SCR and pronounced EEG asymmetry during direct gaze.

Exploratory, the investigators will also investigate whether oxytocin administration influences respiration and the subjective reports on experience of live eye contact.

Lastly (and also exploratory), they will explore whether certain personality traits (as measured by SAAM (state adult attachment measure) and SRS (social responsiveness scale)) influence the modulatory effect of oxytocin on neurological and behavioural responses.

Who Took Part

Enrollment: 56 actual participants took part.

It was open to men only aged from 18 years up to 35 years.

Healthy volunteers could join, not only people with the condition.

Examples of who could join: Age between 18 and 35. Normal or adjusted-to-normal vision (with lenses only). Dutch as mother tongue.

The full record lists 5 inclusion and 5 exclusion criteria; among the exclusions: not right-handed; age below 18 or above 35; need to wear glasses.

How the Study Was Run

The set-up was randomized, parallel-group and triple-blind.

Random assignment meant chance, not the researchers, decided who got Oxytocin and who got the comparison, which limits bias.

The Oxytocin group and the comparison group ran side by side rather than switching.

As a double-blind Oxytocin study, the assignments were hidden from both participants and investigators until the end.

Those kept unaware of assignments: participant, investigator and outcomes assessor.

It started in 2017-07-24 with completion listed for 2018-05-18.

It ran at 1 site in Belgium.

Its stated primary purpose is basic science.

What Was Measured

The main thing measured (primary outcome): Change in EEG asymmetry after oxytocin administration (time frame: Average over several trials, baseline and 40 min after oxytocin or placebo administration). Change in skin conductance (type of electrodermal activity) response after oxytocin administration (time frame: Average over several trials, baseline and 40 min after oxytocin or placebo administration).

It also tracked 2 secondary outcomes, for example Change in duration of fixations to face regions after oxytocin administration and Change in number of fixations to face regions after oxytocin administration.

What This Means in Plain Language

Put simply, this is a phase 1, phase 2, randomized trial of Oxytocin in 56 people.

The trial is marked completed; no results are posted to the registry yet, so nothing here describes outcomes.

More context: the Oxytocin compound page, all human trials.