Antipsychotic drugs are effective in psychoses, whatever the etiology of the disorder. The positive symptoms tend to respond more readily. The need for developing new drugs arises from the refractoriness of the negative symptoms, the 10-25% of the patients that are treatment-resistant and the problems of short-, and long-term extrapyramidal side-effects. Thus far, six drugs, differing from the classical antipsychotics, have been licensedfor use: olanzepine, risperidone and quetiapine; the longest registration exists for sulpiride and clozapine while the most recent one is for amisulpride. This review starts with a brief introduction to symptomatology, and takes differences with the classical drugs in pharmacology, pharmacokinetics, clinical aspects and side-effects into consideration. Clozapine, risperidone and sulpiride may be considered for clinical use in refractory patients; these three, olanzapine and amisulpride when extrapyramidal side-effects cause a clinical problem. Amisulpride and sulpiride have a dual therapeutic acion: On negative symptoms at low dose, on positive symptomen at high doses.

The different forms of antidepressive continuation therapy, used in the Netherlands, to prevent relapse after electroconvulsive therapy, were examined by sending a questionaire to all ECT centers. Common practice is in agreement with the results of current research. However, recent studies suggest that pharmacological continuation therapy is less usefull to prevent relapse when pharmacotherapeutic resistance has been proven in the past. In these cases ECT-continuation therapy might bring a solution. On the effect of ECT-continuation therapy are few valid research results available.

Positron emission tomography is one of the most important techniques of functional imaging in psychiatry. This paper gives a synopsis of the findings in mood disorders: determination of brain glucose metabolism, cerebral blood flow and receptor studies. Investigation in a resting state as well as after activation are discussed.

Although findings are somewhat discrepant hypometabolism, and/or hypoperfusion, most often in frontal and limbic areas are frequently described. Further research is needed, and standardization of the methodology would be most wellcome.

A psychofysiological study of the cardiac adaptivity to attention-demanding reaction time tasks demonstrated that children with a lesser variant of the pervasive developmental disorder (DSM-IV: PDDNOS) exhibit less cardiac responsiveness to attention tasks than healthy children do. We studied changes in heart rate variability (HRV), which were measured in a frequency band ranging from 0.07 to 0.14Hz. During the performance of an attention task, healthy children exhibited task load-related decreases in HRV. These decreases were found to be significantly smaller and not task load-related in a group of children with a PDDNOS who were judged to be not hyperactive. The decreases in HRV during task performance were almost absent in children with a PDDNOS who were moreover judged to be hyperactive. The magnitude of HRV decreases appeared to be significantly related to one of our task performance measures and to behaviour problems reported by the parents. Our results suggest a diminished vagal adaptivity to attention-demanding task situations in children with a PDDNOS, which is related to their resistance to unexpected changes in their daily routines.

Mounting evidence suggests involvement of prenatal factors in the pathogenesis of schizophrenia. The objective of the present study was to provide evidence for the hypothesis on schizophrenia that abnormal fetal brain development leads to impaired sensorimotor gating of acoustic startle stimuli. To this purpose, pregnant rats were treated with methylazoxymethanol acetate on one of four subsequent days of gestation, from E9 to E12. These procedures inhibit early stages of cortical proliferation in the foetuses, resulting in adult brain abnormalities that were mainly found in the entorhinal region. At the adult age, habituation andprepulse inhibition (PPI) of startle responses to acoustic stimuli were investigated. Our results show impaired habituation and PPI in rats treated at embryonic days 10 and 11. It is concluded that sensorimotor gating deficits can result from a developmental abnormality involving the entorhinal region, supporting the hypothesis that similar deficits, often observed in schizophrenic subjects, may be the result of entorhinal cortex dysfunction.