The concept of schizotypy or “psychosis proneness” captures individual differences in perceptual, cognitive and affective experiences that may relate to a range of psychotic disorders. The concept is an important way to assess the contribution of pre-existing psychological and genetically-based biological features to the development of illnesses such as schizophrenia (so called endophenotypes). The Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE) is a widely used multi-dimensional measure of the construct and consists of four scales which mirror several groups of psychotic symptoms: Unusual Experiences (positive symptoms), Cognitive Disorganisation (cognitive symptoms), Introvertive Anhedonia (negative symptoms) and Impulsive Nonconformity (impulsive and antisocial symptoms). For the purpose of evaluating the suitability of schizotypy as an endophenotype of schizophrenia the current version of the Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE) was translated into German: its psychometric properties (incl. re-test reliability and construct validity) were examined in a large sample (n > 1200) and compared to those of the English original. The German version was both highly reliable and consistent with the original. The study aimed to show that schizotypy as measured by the O-LIFE can indeed be regarded as an endophenotype of schizophrenia in terms of genetic associations regarding relevant dopamine-related candidate polymorphisms of schizotypy (i.e. Val158Met-polymorphism of the COMT gene, uVNTR of the MAOA gene, Taq1A-polymorphism of the DRD2 gene, VNTR of the SLC6A3 (DAT) gene). We also wanted to compare the genetic associations of the O-LIFE to those published using other operationalizations of schizotypy. Our results show a large number of significant associations and borderline-significant trends between the O-LIFE sub-scales and a range of genes, thereby supporting using the O-LIFE in the search for endophenotypic markers.

Many individuals with schizophrenia are reported to have maladaptive expression and processing of emotion. This may take the form of conscious and implicit processes. Potential regulatory processes underlying schizophrenia are reviewed. We aimed to estimate effect sizes, potential heterogeneity and publication bias across three areas of measurement: a range of cognitive emotion regulation strategies(1) (CERS), alexithymia and dissociation. Data were pooled from 47 case-control studies involving measures of experiential avoidance, attentional deployment, cognitive reappraisal, emotion management, dissociation and alexithymia. All studies were rated for quality, risk of bias and publication bias. The following effect sizes (g) were observed: emotion management: 0.96 [0.77, 1.14] and cognitive reappraisal: 0.49 [0.32, 0.66] were negatively associated with schizophrenia. Experiential avoidance: -0.44 [-0.59, -0.29], attentional deployment -0.96 [-1.18, -0.75], dissociation: -0.86 [-1.13, -0.60] and alexithymia: -1.05 [-1.45, -0.65] were positively associated with schizophrenia. Subgroups of dissociation and attentional deployment were also analysed. Meta-analyses revealed potential publication bias and heterogeneity in the study of CERS in schizophrenia. A marked difference in the implementation of CERS is associated with schizophrenia compared to controls. Dissociation variables and alexithymia are also indicated and may be implicated in adaptive cognitive emotional regulation. Theoretical and research implications are discussed.