Hanne Schulsinger

Heredity-environment interaction and schizophrenia

The longitudinal prospective study of populations at risk is considered a powerful strategy towards disentangling hereditary and environmental factors. Data from Mednick and Schulsingers 1962 study in Copenhagen, on children at high-risk for schizophrenia are used as an illustration. Pregnancy and birth complications, as well as institutional rearing in early childhood contributes towards schizophrenia in the risk children, but not in the low-risk controls. Risk children with an outcome of schizotypal personality disorder were hardly exposed to perinatal complications. To some extent, schizophrenia may be considered as a complicated form of schizotypal personality disorder, which again may be a genetically transmitted condition.

Continuity of formal thought disorder from childhood to adulthood in a high‐risk sample

ABSTRACT Within a longitudinal prospective study of children of schizophrenic mothers, premorbid, childhood levels of formal thought disorder correlated positively with measures of formal thought disorder obtained in adulthood. It is therefore concluded that schizophrenic symptomatology develops by gradual accretion and that schizophrenia is not a sudden, unexpected disease. Orthogonal factor analysis of formal thought disorder measures obtained in adulthood revealed two factors: one reflecting vague and drifting thinking, and the second relating to the richness of speech.

Continuity of Character neurosis from childhood to adulthood.: A PROSPECTIVE LONGITUDINAL STUDY

In a prospective longitudinal study, stability of personality traits was examined between the age of 15 and the age of 25. Scales, derived from an Adjective Check List, intending to predict obsessive‐ compulsive character neurosis, anti‐aggressive character neurosis and non‐neuromtic personality have been utilized. Temporal stability of the examined personality traits was demonstrated.

Genetics and Classification

Longitudinal studies are always aimed at studying the interaction between genetic predispositions and various experiential factors. If this aim is not conscious to the researchers, they are apt to fail in their research or they need more than usual luck to find anything of real interest.