A positive-psychological intervention reduces acute psychosis-proneness.

BACKGROUND: While individuals at ultra-risk for schizophrenia are characterized by high negative/disorganised but low positive schizotypy, schizophrenia patients are usually high in all three schizotypy facets. Thus, avoiding increases in positive schizotypy in ultra-high risk individuals may constitute of form of schizophrenia-prevention. A possible method of reducing positive schizotypy could be Positive-Psychological intervention (PI). METHODS: We present results from 2 independent studies, including a 12-month follow-up from study 1, using an easy-to-perform intervention based on Positive Psychology to reduce positive schizotypy. RESULTS: A PI can significantly and sustainably reduce positive schizotypy compared to a placebo-condition. Furthermore, our results show very high response-rates to said intervention, with responsiveness to the intervention increasing significantly with disorganised schizotypic traits. CONCLUSIONS: As especially disorganised schizotypy is of relevance for the risk of transition from high benign schizotypy to schizophrenia and is found most closely associated to familial schizophrenia-risk and highly elevated in at-risk mental states, our results are encouraging. We suggest, thus, that positive psychology can not only reduce positive schizotypy, but may be increasingly useful with rising schizophrenia-risk and, thus, be worthy of further investigation regarding it potential in schizophrenia-prevention.

Variations in central serotonergic activity - relevance of the 5-HTTLPR, life events and their interaction.

The 5-HTTLPR and its interaction with adverse life events has been studied widely; especially with regard to depression. Few studies are available relating the respective association with acute serotonergic functionality. We examined the effects of the 5-HTTLPR, life events and their interaction on serotonergic responsivity using S-citalopram (10mg) in a placebo-controlled double-blind neuroendocrine challenge paradigm (n=59 healthy males). We considered positive and negative life events, life events experienced during the last year and accumulated over the whole life span and possible mediating effects of neuroticism, extraversion and openness to experience. We demonstrated associations of life events experienced during the last year: negative life events were positively associated with cortisol-responses in the challenge paradigm (ß=0.28, p<0.05), while positive life events were inversely associated (ß=-0.29, p<0.05). Neither the main effect of 5-HTTLPR-genotype nor its interactions with life events predicted the acute serotonergic functionality. In addition, openness for feelings significantly predicted the serotonergic responsivity, while no other personality traits measured in this study mediated the effect of life events. Our results question not only the stability of serotonergic activity but, importantly, add to the literature concerning the serotonergic system as a general threshold modulating system, i.e. being associated with the processing of positive as well as negative stimuli.

A false-positive detection bias as a function of state and trait schizotypy in interaction with intelligence.

Hallucinatory experiences are by far not limited to patients with clinical psychosis. A number of internal and external factors may bring about such experiences in healthy individuals, whereby the personality trait of (positive) schizotypy is a major mediator of individual differences. Psychotic experiences are defined as associating abnormal meaning to real but objectively irrelevant perceptions. Especially, the ambiguity of a stimulus correlates positively with the likelihood of abnormal interpretation, and intelligence is believed to have an important influence and act as protective against clinical psychosis in highly schizotypic individuals. In this study, we presented 131 healthy participants with 216 15-letter strings containing either a word, a non-word, or only random letters and asked them to report, whether or not they believed to have seen a word. The aim was to replicate findings that participants with high values in positive schizotypy on the trait-level make more false-positive errors and assess the role of stimulus-ambiguity and verbal intelligence. Additionally, we wanted to examine whether the same effect could be shown for indices of state schizotypy. Our results support findings that both state and trait positive schizotypy explain significant variance in "seeing things that are not there" and that the properties of individual stimuli have additional strong effects on the false-positive hit rates. Finally, we found that verbal intelligence and positive schizotypy interact with stimulus-ambiguity in the production of false-positive perceptions.