Skip to main content
OpenTrials
Completed

NCT Number: NCT03891459

Neural Account of Social Placebo Effect

The current study aimed to reveal the neural mechanism of social placebo belief formation and belief representation, and also investigated how the brain pattern predict the social behavior performance under placebo manipulation.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Spray+ Group Control Group

Age range

18 year–35 year

Sex eligibility

Male

Study type

Interventional

Phase

Not applicable

Primary location

Beijing Normal University

Beijing, Beijing Municipality, 100000, China

About this study

Participants were randomly assigned to spray+ group (sprayed with saline but told as "oxytocin") and control group (sprayed with saline but told as "saline"). After 10 min, participants were invited to the resting-state, text viewing task in fMRI scanner.

In resting state session, participants with their eyes open and were instructed to attend to a black fixation cross centrally presented on a grey projection screen for 8 min (240TR).

The Text viewing task employed a mixed block and even-related fMRI design. Participants were asked to judge whether they could understand the stimuli or not by a button press (1=understand; 2=not understand). Three kinds of stimuli were presented in separate block including "oxytocin-function", "oxytocin-knowledge", "robot" related stimuli, each category contained 20 sentences. In each block, the sentence (within one category) was presented pseudo-randomized from 5s to 9s (with mean duration of 7s), then followed by a jittered time interval (interval time = sentence duration - response time; if participants made response within 5s, the sentence would not disappear until its duration reached 5s). There were two sessions with six blocks per session, and there were 5 sentences (trials) per block. The order of blocks and sentences were designed to present in pseudo-random order and were applied to all participants.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • All participants had normal or corrected-to-normal vision, and mental healthy.

Exclusion criteria

  • Participants who reported no history of neurological, endocrine or psychiatric disorders, who majored in psychology in college or recently participated in any other drug study were not recruited.

Treatment and study plan

spray+ manipulation

Behavioral

Participants in spray+ group received placebo manipulation and were told they sprayed was oxytocin (in fact, it was saline);

control manipulation

Behavioral

Participants in control group were told they sprayed saline (in fact, it was saline).

Primary outcomes

  1. The brain functional connectivity

    Time frame: 8 mins, 240 TR in scanner

    For functional connectivity estimation, we adopted DLPFC, mPFC and reward related brain regions as the seeds to do whole-brain connectivity analysis. And the conducted two-sample T test to examine whether there would be some differences between spray+ and control groups.

  2. Social brain network properties in resting-state

    Time frame: 8 mins, 240 TR in scanner

    For the network properties, we chose the social brain network as our target and interested network, then estimated the global efficiency within this network.And the conducted two-sample T test to examine whether there would be some differences between spray+ and control groups.

  3. The brain response pattern for the key concepts about oxytocin

    Time frame: 5.33mins, 160TR in scanner

    We estimated the beta response trial by trial for each single concept and then investigated the neural representation of all concepts by using representational similarity analysis (RSA).

Sponsors and collaborators

Lead sponsor

Beijing Normal University

Other

Registry information

Important dates

Study start
2018
Primary completion
2018
Study completion
2018
First posted
Mar 27, 2019
Registry last updated
Mar 27, 2019

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.