The main aim of the study is to investigate whether intranasal oxytocin (24IU) can enhance hedonic experience and associated brain-reward reward responses to social touch.

A double-blind, within-subject, placebo controlled design is employed in this study. In total 50 healthy male subjects will be recruited and they will come twice, once with the administration of oxytocin nasal spray and the other placebo (interval time is more than 2 weeks). 45 minutes after treatment subjects will be applied two different types of pleasant touch: social touch from a masseur (professional therapist) and non-social touch from a massage device. After each condition the subjects will be asked to rate pleasantness, likability, and arousal. Simultaneously functional brain activity will be acquired via fMRI. Blood samples will be taken before and after the intervention to assess oxytocin levels. All subjects were asked to complete a range of questionnaires measuring trait personality and mood: Beck Depression Inventory (BDI), Cheek and Buss Shyness Scale (CBSS),Autism Spectrum Quotient (ASQ), Empathy Quotient (EQ), NEO Five Factor Inventory (NEO-FFI), Liebowitz Social Anxiety Scale (LSAS),Behavioral Inhibition System and Behavioral Activation System Scale (BISBAS),Sensitivity to Punishment and Sensitivity to Reward Questionnaire (SPSRQ),State-Trait Anxiety Inventory (STAI), Social Touch Questionnaire (STQ), Sensory over Responsivity Scale (SOR) and Under Responsivity Scale (URS) one day before the first scanning. On the first and second scanning day, the subjects were asked to complete Positive and Negative Affect Schedule (PANAS) before and after treatment administration.

Inclusion Criteria:

• Healthy subjects without any past or present psychiatric or neurological disorders

Exclusion Criteria:

• History of brain injury
• Medical or mental illness