The Electroretinogram as a Potential Biomarker of Psychosis in Children at Familial Risk.

We previously proposed the electroretinogram (ERG) as a promising biomarker of major psychiatric disorders such as schizophrenia (SZ) and bipolar disorder (BP), given that we found anomalies in the ERG parameters of patients with these diagnoses as well as in their children who are at high risk (HR) of developing such disorders. The aim of the present study is to investigate the usefulness of the ERG for individual detection, among HR children, of an ERG profile resembling that of a SZ patient, as this may indicate a stronger likelihood of transition to psychosis. Using a logistic regression model previously derived from the ERG assessments of SZ patients and control (CT) subjects, individual risk scores were obtained for 61 HR and 80 CT youth.

The Electroretinogram May Differentiate Schizophrenia From Bipolar Disorder.

Background: The retina is recognized as an approachable part of the brain owing to their common embryonic origin. The electroretinogram (ERG) has proved to be a valuable tool to investigate psychiatric disorders. We therefore investigated its accuracy as a tool to differentiate schizophrenia (SZ) from bipolar disorder (BP) even after balancing patients for their main antipsychotic medication.

Retinal function anomalies in young offspring at genetic risk of schizophrenia and mood disorder: The meaning for the illness pathophysiology.

Background: Visual defects are documented in psychiatric disorders such as schizophrenia, bipolar disorder and major depressive disorder. One of the most consistent alterations in patients is a change in cone and rod electroretinographic (ERG) responses. We previously showed a reduced rod b-wave amplitude in a small sample of young offspring born to an affected parent.

Cognitive structure from childhood to adulthood in kindreds densely affected by schizophrenia and bipolar disorder.

The developmental aspects of cognitive structures from childhood until adulthood and across different levels of risk for psychopathology have been little studied. The aim of the current study was to explore the cognitive factorial structure in subsamples from highly familial and densely affected kindreds of schizophrenia and bipolar disorder - i.e.

Childhood abuse and neglect may induce deficits in cognitive precursors of psychosis in high-risk children.

Background: Millions of children are born to parents affected by major psychoses. Cognitive dysfunctions seen in patients are already detectable in these children. In parallel, childhood maltreatment increases the risk of adult psychoses through unknown mechanisms.

Symptom dimensions as alternative phenotypes to address genetic heterogeneity in schizophrenia and bipolar disorder.

This study introduces a novel way to use the lifetime ratings of symptoms of psychosis, mania and depression in genetic linkage analysis of schizophrenia (SZ) and bipolar disorder (BP). It suggests using a latent class model developed for family data to define more homogeneous symptom subtypes that are influenced by a smaller number of genes that will thus be more easily detectable. In a two-step approach, we proposed: (i) to form homogeneous clusters of subjects based on the symptom dimensions and (ii) to use the information from these homogeneous clusters in linkage analysis.

Young offspring at genetic risk of adult psychoses: the form of the trajectory of IQ or memory may orient to the right dysfunction at the right time.

Objective: Neurocognitive dysfunctions analogous to those of adult patients have been detected in children at risk of schizophrenia and bipolar disorder. This led to the following developmental question: Do IQ and memory impairments exhibit different developmental courses from childhood to young adulthood in terms of stability or fluctuations?

Methods: In a high risk sample, we used a step by step sampling approach to narrow-down the early disease mechanisms. Upstream, we started with a 20-year follow-up of 48 densely affected multigenerational kindreds, including 1500 clinically characterized adult members.