Increased rigidity with age in social behavior of Java-monkeys (Macaca fascicularis).

In this study we investigated the effect of aging on the structure of behavior of socially housed Java-monkeys. Indices of the sequential structure of an animal's own ongoing behavior and of its responses to behavior of other animals were calculated using an information statistic approach. These indices reflect information-processing abilities of an animal, as they represent the ability of an animal to adjust its behavior in response to actions by interaction partners.

Aging, dominance history, and social behavior in Java-monkeys (Macaca fascicularis).

The aim of this study was to investigate the influence of the dominance history of socially housed Java-monkeys on the aging process. In monkeys, social subordinance is generally associated with elevated levels of cortisol, which, in turn, have been suggested to influence cognitive decline. As cognitive skills are necessary for successful social life, we investigated the effect of old age in relation to the dominance history of the animals on their social behavior by comparing old females with their younger daughters.

Differential kinship effect on reconciliation in three species of macaques (Macaca fascicularis, M. fuscata, and M. sylvanus).

Macaque societies are typically characterized by despotic dominance styles and strong bonds between related individuals. Interspecies variation in dominance style, however, has been recently documented. This study investigated whether kinship effects on social interactions vary depending on the species dominance style.

Methodological improvements for the study of reconciliation.

The present paper suggests methodological improvements for the study of reconciliation, i.e. affiliative interactions between former opponents shortly after agonistic conflicts.

[Early diagnosis of fragile X mental retardation syndrome].

Conducting an inquiry among 32 parents of 46 children with fragile-X mental retardation, we investigated the problems on early recognition of the syndrome. From the first call for medical help until establishment of the diagnosis, on average 2 years elapsed. The family history is very important, since in 82.