Short- and long-term effects of oxytocin on empathy and social behaviour in autistic and antisocial male adults. - Oxytocin effects in autistic and antisocial male adults

Recruitment & Eligibility

Status: Authorised-recruitment may be ongoing or finished

Sex: Male

Target Recruitment: Not specified

Inclusion Criteria

1. All participants must be male and be in the age range of 18 to 30 years. We decided to investigate only males because the prevalence of both ASD and APD is higher (about 4 times) in males than in females and because sex differences have been found in neuropeptide systems as well as in the processing of socially positive vs. negative information. The choice for investigating males up from the age of 18 is based on the findings that dopamine levels peak in early adolescence and that dopamine has been found to interact with OT expression.
2. All participants must have an IQ of 80 or higher.
3. All participants must have normal or corrected to normal vision.

Additional inclusion criteria for the specific groups:

Participants with ASD:
1. Clinical score on the adult module (V) of the Autism Diagnostic Observation Scale (ADOS). This instrument is a widely accepted and internationally used gold standard for obtaining reliable ASD diagnoses.

Participants with APD:
1. (Previous) DSM-IV diagnosis of an early onset Conduct Disorder.
2. Clinical score on a structured clinical interview for diagnosing DSM-IV axis-II antisocial personality disorders (the SCID-II).
3. A score of 30 or more on the Psychopathy Checklist-Revised (PCL-R) by Hare (1991) which is a semi-structured interview consisting of 20 items to be rated on a 2-point scale by a professional. Yielding a maximum total score of 40, a score of 30 or more is recommended by Hare to identify the prototypical psychopath with a majority of these individuals meeting the criteria for APD. To ensure the inclusion of only highly callous, remorseless individuals in our APD group, we will principally adopt this criterion. If this, however, will result in too a small number of participants left we will lower the criterion.

Are the trial subjects under 18? no
Number of subjects for this age range:
F.1.2 Adults (18-64 years) yes
F.1.2.1 Number of subjects for this age range
F.1.3 Elderly (>=65 years) no
F.1.3.1 Number of subjects for this age range

Exclusion Criteria

1. Participants may not have a nasal congestion due to cold or allergies.
2. All participants must be free of psychotropic medication or neuroleptics and stimulant medication. They may not have a history of alcohol or drug dependence.
3. For the empathy experiment, all participants are required to abstain from stimulants, XTC, soft drugs and alcohol for about 20 h, from caffeine for about 4 h and from cigarette smoking and taking food for 2 h before testing. This will, in the first place, rely on informed consent. The use of cocaine, amphetamine, methamphetamine, cannabis and XTC will be controlled for by saliva samples taken before starting the experiment. Blood serum controls will be carried out on the use of methylphenidate and alcohol. Participants who did not abstain for the time of the experiment will be excluded from further participation or data analysis.

Study & Design

Study Type: Interventional clinical trial of medicinal product

Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Main Objective: To investigate the effectiveness of 4-weeks treatment with intranasally adminsitered oxytocin twice a day versus placebo in improving social behaviour in patients with antisocial personality disorder and in those with autism spectrum disorder;Secondary Objective: To identify predictors of treatment effectiveness;Primary end point(s): Our primary outcome measures will be social functioning as assessed by (1) the Social Responsiveness Scale (the SRS-A) to be completed by an adult informant who knows the participant in naturalistic social settings and (2) by a symptom checklist to be completed by the participant himself, i.e. the SCL 90 that has been used for treatment studies in forensic settings before.

Secondary Outcome Measures