Several neurological variables have been investigated as premorbid biomarkers of vulnerability for schizophrenia and other related disorders. The current study examined whether childhood dyspraxia predicted later adult nonaffective–psychosis-spectrum disorders. From a standardized neurological examination performed with children (aged 10–13) at genetic high risk of schizophrenia and controls, several measures of dyspraxia were used to create a scale composed of face/head dyspraxia, oral articulation, ideomotor dyspraxia (clumsiness), and dressing dyspraxia (n = 244). Multinomial logistic regression showed higher scores on the dyspraxia scale predict nonaffective–psychosis-spectrum disorders relative to other psychiatric disorders and no mental illness outcomes, even after controlling for genetic risk, χ2 (4, 244) = 18.61, p < .001. Findings that symptoms of dyspraxia in childhood (reflecting abnormalities spanning functionally distinct brain networks) specifically predict adult nonaffective–psychosis-spectrum disorders are consistent with a theory of abnormal connectivity, and they highlight a marked early-stage vulnerability in the pathophysiology of nonaffective–psychosis-spectrum disorders.

Although allostatic load has been investigated in mood and anxiety disorders, no prior study has investigated developmental change in allostatic load as a precursor to schizotypal personality. This study employed a multilevel developmental framework to examine whether the development of increased allostatic load, as indicated by impaired sympathetic nervous system habituation from ages 3 to 11 years, predisposes to schizotypal personality at age 23 years. Electrodermal activity to six aversive tones was recorded in 995 subjects at age 3 years and again at 11 years. Habituation slopes at both ages were used to create groups who showed a developmental increase in habituation (decreased allostatic load), and those who showed a developmental decrease in habituation (increased allostatic load). Children who showed a developmental increase in allostatic load from ages 3 to 11 years had higher levels of schizotypal personality at 23 years. A breakdown of total schizotypy scores demonstrated specificity of findings to cognitive–perceptual features of schizotypy. Findings are the first to document a developmental abnormality in allostasis in relation to adult schizotypal personality. The relative failure to develop normal habituation to repeated stressors throughout childhood is hypothesized to result in an accumulation of allostatic load and consequently increased positive symptom schizotypy in adulthood.

Background. This study examined data from a Danish prospective longitudinal project in attempt to address the state/trait controversy regarding theory of mind deficits in schizophrenia. Deficits in perspective-taking – a component of theory of mind – were investigated prospectively among children who developed schizophrenia spectrum disorders as adults in comparison to children who did not develop schizophrenia spectrum disorders.

Method. A total of 265 high risk and control subjects were studied in 1972. At the time of initial assessment, the Role-Taking Task (RTT) was administered. Two hundred and forty-two of these children were evaluated in 1992 during follow-up examinations. Sixteen developed schizophrenia, 10 developed a schizophrenia spectrum disorder, 70 had outcomes of other psychopathology, and 146 did not develop a mental illness.

Results. Children who later developed schizophrenia or a schizophrenia spectrum disorder had lower RTT scores, controlling for verbal IQ and age, compared to those who did not develop any mental illness. Although in the expected direction, RTT scores for those with schizophrenia spectrum disorders were not significantly different from those who developed a non-psychotic disorder.

Conclusions. Deficits in perspective-taking among children who later developed schizophrenia spectrum disorders suggest that a facet of theory of mind is impaired prior to development of schizophrenia. Our findings lend support to the hypothesis that theory of mind deficits in schizophrenia are trait markers of the disorder.

Previous studies have repeatedly shown verbal intelligence deficits in adolescent antisocial individuals, but it is not known whether these deficits are in place prior to kindergarten or, alternatively, whether they are acquired throughout childhood. This study assesses whether cognitive deficits occur as early as age 3 years and whether they are specific to persistently antisocial individuals. Verbal and spatial abilities were assessed at ages 3 and 11 years in 330 male and female children, while antisocial behavior was assessed at ages 8 and 17 years. Persistently antisocial individuals (N = 47) had spatial deficits in the absence of verbal deficits at age 3 years compared to comparisons (N = 133), and also spatial and verbal deficits at age 11 years. Age 3 spatial deficits were independent of social adversity, early hyperactivity, poor test motivation, poor test comprehension, and social discomfort during testing, and they were found in females as well as males. Findings suggest that early spatial deficits contribute to persistent antisocial behavior whereas verbal deficits are developmentally acquired. An early-starter model is proposed whereby early spatial impairments interfere with early bonding and attachment, reflect disrupted right hemisphere affect regulation and expression, and predispose to later persistent antisocial behavior.

Little is known about the effects of environmental enrichment on psychophysiological measures of arousal and orienting in humans. This study tests the hypothesis that early educational and health enrichment is associated with long-term increases in psychophysiological orienting and arousal. One hundred children were experimentally assigned to a two-year enriched nursery school intervention at ages 3–5 years and matched at age 3 years on psychophysiological measures, gender, and ethnicity to 100 comparisons who received the normal educational experience. Children were retested 6–8 years later at age 11 years on skin conductance (SC) and electroencephalogram (EEG) measures of arousal and attention during pre- and postexperimental rest periods and during the continuous performance task. Nursery enrichment was associated with increased SC amplitudes, faster SC rise times, faster SC recovery times, and less slow-wave EEG during both rest and CPT conditions. This is believed to be the first study to show that early environmental enrichment is associated with long-term increases in psychophysiological orienting and arousal in humans. Results draw attention to the important influence of the early environment in shaping later psychophysiological functioning.

Our findings in the Helsinki Influenza Study and the Danish Forty Year Study lead us to conclude that a 2nd-trimester maternal influenza infection may increase risk for adult schizophrenia or adult major affective disorder. More recently we have also reported an increase of unipolar depression among offspring who were exposed prenatally to a severe earthquake (7.8 on the Richter scale) in Tangshan, China. Among the earthquake-exposed males (but not the females), we observed a significantly greater depression response for those individuals exposed during the 2nd trimester of gestation. These findings suggest that maternal influenza infection and severe maternal stress may operate (in different ways) as teratogens, disrupting the development of the fetal brain and increasing risk for developing schizophrenia or depression in adulthood.

Background The current study examines teacher ratings as a tool for identifying students at risk of developing psychosis. Follow-up and follow-back studies have shown that teachers are capable of identifying individuals who later develop serious mental illness.

Method We examine the long-term outcomes for individuals at genetic risk who were identified as showing markedly deviant behaviour and those identified who did not show markedly deviant behaviour.

Results Teachers were able to correctly anticipate 35% of students who developed schizophrenia. Furthermore, those identified as showing markedly deviant behaviour had poorer clinical and psychiatric outcomes 10 and 25 years later than those identified as not behaving with marked deviance. Their ratings also differentiated, within the group of people with schizophrenia, which individuals would show evidence of poorer functioning 25 years later. These results were replicated in a group of students not at genetic risk of schizophrenia. Within this low-risk group, teachers were able to predict which students would develop psychotic disorders.

Conclusions Teacher ratings were particularly useful in predicting clinical and psychiatric outcomes 10 and 25 years later. The applicability of these findings in early intervention and treatment research is discussed.