Toxicology is one of the eldest areas of special attention in medicine and pharmacy. In the past, forensic toxicology was the most important part, but nowadays, at least in the Netherlands, the clinical, occupational and environmental toxicology have the centre of attention.

The brain plays its own role in the clinical toxicology. There the intoxication can take place, it can be the basis of the peripheral symptoms of the intoxication or it can be the cause of the intoxication, e.g. at a suicidal attempt or the hospital addiction syndrome.

The somatic treatment of an intoxicated patient includes in the first place the stabilization of the patient (cardio-vascular, ventilation and central effects); then the removal of the poison from the surroundings and out of the patient by different suitable methods and finally the symptomatic treatment, sometimes with antidotes.

In the Netherlands, hardly any intoxication is fatal, when the patient arrives in the hospital in time, or euthanasia took place on purpose.

Huntington's disease (HD) is an autosomal dominant disorder of the central nervous system, characterised by neurological, cognitive and psychiatric pathology. Recently the causative genetic defect was discovered. We present a retrospective study of 59 HD patients, investigating correlations between molecular and clinical data.

The correlation between CAG-repeatlength and age at onset is confirmed. No correlations between this biological marker and other clinical features are found (symptoms at onset, mode of progression of the disease).

The consequences of these findings for predictive testing are discussed. Furthermore, a short overview of the predictive testing procedure in the Center for Human Genetics in Leuven (Belgium) is given.

In een vergrijzende bevolking neemt de prevalentie van psychogeriatrische patiënten toe. Die toename hangt onder meer samen met de met de leeftijd toenemende kwetsbaarheid van het brein. Deze beschouwing gaat over die samenhang.

In 1972 is door de Wereldgezondheidsorganisatie het begrip ‘psychogeriatrie’ omschreven als een tak van de psychiatrie die zieh bezig houdt met die psychische stoornissen die zieh voor het eerst op oudere leeftijd manifesteren en duidelijk oorzakelijk samenhangen met de maatschappelijke, geestelijke en lichamelijke veranderingen in de derde levensfase.

An interactional model of brain function is postulated, in which activity and reactivity are basic properties of the central nervous system from the very beginning. Variability is an essential aspect of normal functioning. Primary or indiscriminate variability consists of the development of many strategies for the execution of motor acts. It is predominant during fetal age and infancy. Toddler age is characterized by secondary or adaptive variability, which reflects the ability to select the adequate strategy at the right moment. This is important for the development of proper planning of movement patterns and is a prerequisite for skill development. Recognition of the types and quality of variability helps to detect developmental disorders at an early age.