The Netherlands Twin Register (NTR) began in 1987 with data collection in twins and their families, including families with newborn twins and triplets. Twenty-five years later, the NTR has collected at least one survey for 70,784 children, born after 1985. For the majority of twins, longitudinal data collection has been done by age-specific surveys. Shortly after giving birth, mothers receive a first survey with items on pregnancy and birth. At age 2, a survey on growth and achievement of milestones is sent. At ages 3, 7, 9/10, and 12 parents and teachers receive a series of surveys that are targeted at the development of emotional and behavior problems. From age 14 years onward, adolescent twins and their siblings report on their behavior problems, health, and lifestyle. When the twins are 18 years and older, parents are also invited to take part in survey studies. In sub-groups of different ages, in-depth phenotyping was done for IQ, electroencephalography , MRI, growth, hormones, neuropsychological assessments, and cardiovascular measures. DNA and biological samples have also been collected and large numbers of twin pairs and parents have been genotyped for zygosity by either micro-satellites or sets of short nucleotide polymorphisms and repeat polymorphisms in candidate genes. Subject recruitment and data collection is still ongoing and the longitudinal database is growing. Data collection by record linkage in the Netherlands is beginning and we expect these combined longitudinal data to provide increased insights into the genetic etiology of development of mental and physical health in children and adolescents.

The question whether symptom-free migraine patients show cognitive impairments compared to matched control subjects is addressed, and also whether migraine patients show transient cognitive impairments induced by an attack. The Neuropsychological Evaluation System (NES2) was administered once in an interictal period and twice within 30 h after different migraine attacks. Since cognitive impairments could be related to attack duration or severity, cognitive performance was compared during a postictal period after sumatriptan use and during a postictal period after habitual nonvasoactive medication use. Twenty migraineurs without aura, 10 migraineurs with aura, and 30 matched headache-free controls participated in the study. During a headache-free period, migraineurs without aura responded as quickly as controls, while migraineurs with aura were slower than controls during all tasks specifically requiring selective attention. These effects were not aggravated by a preceding migraine attack, irrespective of medication use and attack duration. studies have provided evideficits in migraine patients, control. These results, along with limited food tolerance, tiredness, altered mood state, and diurincluding psychomotor deficiencies (1, 2), memory deficits (2,3), and dysfunctions in the early stages of visual processing (4, 5), especially in migraineurs with aura (3, 6, 7). However, in other studies, neither detrimental cognitive effects in migraine patients nor differences between migraineurs with and without aura have been found (8, 9). Factors that could contribute to these inconsistent results are patient selection biases, a lack of distinction between migraineurs with aura and migraineurs without aura, the absence of matched control groups, and the presence of type I errors as a result of multiple testing without adjustment of the nominal alpha level. The time interval between a migraine attack and task performance can also be an important factor. Inter&al brain functioning can be influenced by functional or structural effects of migraine on the one hand, and temporal and reversible effects of an attack on the other. Cognitive performance can be temporarily adversely affected by the physiological dynamics of a preceding or upcoming migraine attack. Post-attack effects can be pronounced, since a migraine 'headache is followed by transient physiological alterations remaining for up to 48 h after an attack, e.g., regional cerebral blood flow abnormalities (lo), a reduction of alpha activity within the background EEG (11), and a reduction of the Contingent Negative Variation amplitude (12+an event-related cortical potential reflecting noradrenergic arousal and dopaminergic motor esis (13), suggest a physiological recovery phase which could also lead to an impaired cognitive performance in the post-attack period.The present study addresses two main questions: the first whether migraine patients show cognitive impairments in an interictal period compared to matched headache-free control subjects; the second whether migra...

Headache parameters, personality variables and stress factors were assessed in a sample of about 2,300 school pupils between 10 and 17 years of age in Amsterdam. More than 15% of the subjects reported headaches occurring weekly. Fear of failure and school problems, but not achievement motivation, had significant positive correlations with headache complaints after correction for differences in sex and age. Menarche and social class had little bearing in relation to the headache variables. From all reported causes of headache, stress was mentioned most frequently in both elementary and secondary schools.

The primary goal of the present study was to examine whether in the elderly with mild cognitive impairment (MCI), the effect of physical activity measured directly following treatment, was reflected in an improvement in cognitive functioning in general or in executive functions (EF) in particular. Secondly, this study aimed to compare the effectiveness of two types of intervention, with varying intensities: walking and hand/face exercises. Forty-three frail, advanced elderly subjects (mean age: 86) with MCI were randomly divided into three groups, namely, a walking group (n ¼ 15), a group performing hand and face exercises (n ¼ 13), and a control group (n ¼ 15). All subjects received individual treatment for 30 minutes a day, three times a week, for a period of six weeks. A neuropsychological test battery, administered directly after cessation of treatment, assessed cognitive functioning. The results show that although a (nearly) significant improvement in tasks appealing to EF was observed in both the walking group and the hand/face group compared to the control group, the results should be interpreted with caution. Firm conclusions about the effectiveness of mild physical activity on EF in the oldest old can only be drawn after studies with larger number of subjects.

In a study of 1600 Dutch adolescent twin pairs we found that 59% of the inter-individual variation in