ABSTRACT
This chapter fosuses on dopamine (DA), which has been linked to schizotypy primarily because of classical antipsychotic agents are known to block or to stabilise DA activity at moderate levels and DA-promoting substances such as amphetamine induce or exacerbate psychotic symptoms. It explores this putative link by describing relevant psychopharmacological studies in both patients and healthy individuals where schizotypy is measured. It should be noted that cannabis is also relevant to the DA system. DA is the main potential neurotransmitter relevant to schizotypy and its associated cognitive functions, already indisputably linked to schizophrenia. DA-relevant findings have been seen predominantly with regard to behavioural and cognitive functions, and also using brain imaging. However, both behavioural paradigms and results are highly variable. Comparable to DA antagonistic actions, deficits after a DA agonist are absent for moderate-to-high schizotypes, while they are observable in low schizotypes. This latter observation might point to compensatory mechanisms in healthy individuals with elevated positive schizotypy.
