The primary objective of this study is to identify any interaction between oxytocin and serotonin on neural and behavioral activity related to social reward and decision making by a double-blind, placebo-controlled, between-subject, pharmacological fMRI design
Serotonin and oxytocin have been proved to play an important role in social reward processing and decision making in human. The aim of this study is to determine whether they interact in those essential human behaviors by a double-blind, placebo-controlled, between-subject, pharmacological fMRI design, in which 4 groups of healthy males will be administered with a random combination of nasal oxytocin (24 international units, IU) or placebo and acute tryptophan depletion (ATD, 75.2g) or placebo (a tryptophan-balanced mixture, 78.2g). The social-reward related neural activity and behavior will be assessed by a series of social reward task in and out of fMRI scanner and the decision making will be assessed by reversal learning task, ultimatum game (UG) and loss aversion task. The interaction between serotonin and oxytocin on brain networks will also be tested by resting state.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
BASIC_SCIENCE
Masking
DOUBLE
Enrollment
100
intranasal administration of oxytocin (24 IU)
oral administration of ATD (75.2g) (Acute Tryptophan Depletion)
intranasal administration of placebo nasal spray
Beijing Normal University
Beijing, China
RECRUITINGChanges in brain neural activity during the social reward processing as assessed via fMRI
Whole brain and region of interest (ROI) regression analysis will be used to compare the neural activity of participants in response to social reward task in different treatment groups.
Time frame: approximately 45 minutes after intranasal administration of oxytocin, or placebo, approximately 5.5h after administration of ATD, or placebo
Changes in the resting state as assessed via fMRI
Resting state activity in the social reward related and decision making brain networks will be compared between the treatment groups
Time frame: Time Frame: approximately 45 minutes after intranasal administration of oxytocin, or placebo, approximately 5.5h after administration of ATD, or placebo
Associations with Personalities of subjects
Personalities of subjects will be measured by a series of scales related to decision making and social reward, such as the Sensitivity to Punishment and Sensitivity to Reward Questionnaire (SPSRQ), which measures participants' sensitivity to reward and punishment. SPSRQ is a self-reported instrument that includes 48 yes/no questions divided into two subscales: Sensitivity to Reward (SR, 24 items, ranging from 0 (insensitive) to 24 (sensitive) to reward) and Sensitivity to Punishment (SP, 24 items, ranging from 0 (insensitive) to 24 (sensitive) to punishment). Associations between individual differences in personalities of subjects and differences in behaviors will be measured.
Time frame: before 30mins ATD or placebo administration
Behavioral performance in decision making task
Behavioral performance in reversal learning task will be measured and compared between treatment groups.
Time frame: approximately 4h after administration of ATD, or placebo, before nasal spray
Behavioral performance in social reward related task
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
oral administration of a tryptophan-balanced mixture (78.2g)
Behavioral performance will be measured and compared between treatment groups
Time frame: approximately 105 minutes after intranasal administration of oxytocin, or placebo, approximately 6.5h after administration of ATD, or placebo