<br>        Inclusion Criteria:<br><br>          -  Written informed consent of the subject. For individuals younger than 18 years of age<br>             the parents / legal representatives need to give consent, and the subject can provide<br>             assent (whether the latter is required depends on local laws and regulations).<br><br>          -  UHR diagnosis as made using the Comprehensive Assessment of At-Risk Mental States<br>             (CAARMS) (Yung et al., 2005). Subjects have to meet one or more of the following<br>             criteria: (a) attenuated psychotic symptoms, (b) brief limited intermittent psychotic<br>             symptoms (a history of one or more episodes of frank psychotic symptoms that resolved<br>             spontaneously within 1 week in the past year), or (c) either the presence of<br>             schizotypal personality disorder or a family history of psychosis in a first-degree<br>             relative, all three together with a recent decline in function.<br><br>        Exclusion Criteria:<br><br>          -  Any clinically significant medical condition that may influence the results of the<br>             trial or affect the ability to take part in a trial.<br><br>          -  Laboratory screening values considered clinically relevant by a medical doctor for<br>             transaminases, thyroid hormones or coagulation parameters<br><br>          -  Current or past DSM-IV diagnosis of psychosis, as measured with K-SADS-PL<br><br>          -  Current treatment with an antipsychotic or mood-stabilising agent<br><br>          -  Intake of an antipsychotic or mood-stabilising agent in the two weeks prior to study<br>             inclusion<br><br>          -  Intake of an antipsychotic agent equivalent to a total haloperidol use of >50 mg in<br>             the six months prior to study inclusion<br><br>          -  A first-degree relative (i.e. parents, offspring or siblings) participating in this<br>             study<br><br>          -  UHR diagnosis on the basis of attenuated psychotic symptoms that are entirely<br>             explained by acute intoxication<br><br>          -  Current aggression or dangerous behaviour (PANSS G14 score 5 or above)<br><br>          -  Current suicidality / self-harm (PANSS G6 score 7)<br><br>          -  Current DSM-IV diagnosis of alcohol or substance dependence as measured with K-SADS-PL<br><br>          -  Any current or previous neurological disorder, including epilepsy<br><br>          -  History of head injury resulting in unconsciousness lasting at least 1 hour<br><br>          -  IQ < 70<br><br>          -  More than 4 weeks of regular omega-3 supplementation (>2 daily capsules standard<br>             strength providing >600 mg combined EPA/DHA) within the last 6 months.<br>