Because aggressive behavior during early childhood has been related to negative developmental outcomes, a further understanding of the underlying mechanisms of aggression during the first years of... Show moreBecause aggressive behavior during early childhood has been related to negative developmental outcomes, a further understanding of the underlying mechanisms of aggression during the first years of life is essential. Although the factors prenatal risk, parenting behavior, temperament and cognitive functions have consistently been related to externalizing behavior during preschool and school age, research focusing on their interplay in relation to aggressive behavior earlier in life is scarce. The aim of the current dissertation was to gain more insight into these associations during infancy and toddlerhood. Our studies indicated that impairments in children’s early cognitive regulation abilities play a role in the development of aggressive behavior. It can also be concluded that both adverse pre- and postnatal environmental influences have an impact on child aggression: higher prenatal risk and adverse parenting behavior were directly or indirectly (via poor cognitive functioning) related to higher levels of aggression. In addition, it was found that poor cognitive skills increased the risk of aggression in case of high prenatal risk or a highly reactive temperament during early development. These results suggest that early intervention programs to prevent aggression should focus on prenatal risk, parenting behavior and cognitive development during the first years of life. Show less
Kinderen die op jonge leeftijd een hoge mate van agressief gedrag laten zien hebben een verhoogd risico op problemen later in de ontwikkeling. Blootstelling aan risicofactoren tijdens de prenatale... Show moreKinderen die op jonge leeftijd een hoge mate van agressief gedrag laten zien hebben een verhoogd risico op problemen later in de ontwikkeling. Blootstelling aan risicofactoren tijdens de prenatale periode is in verband gebracht met de ontwikkeling van agressief gedrag. Echter, de mate waarin deze risicofactoren de ontwikkeling van het kind beïnvloeden hangt deels af van de eigenschappen van het individuele kind, waaronder het vermogen tot zelfregulatie. In dit proefschrift is onderzocht hoe zelfregulatie, gemeten op fysiologisch, emotioneel en cognitief niveau, en prenatale risicofactoren de kwetsbaarheid voor agressief gedrag in de vroege kinderleeftijd vergroten en in hoeverre prenatale risicofactoren samenhangen met vroege zelfregulatie. Geconcludeerd kan worden dat 1) kinderen in de voorschoolse leeftijd met een verhoogde mate van agressief gedrag gekenmerkt worden door een specifieke combinatie van tekorten in zelfregulatie op emotioneel en cognitief niveau, 2) de impact van prenatale risicofactoren op de ontwikkeling van fysieke agressie in de peuterleeftijd afhankelijk is van fysiologische zelfregulatie in de babytijd, en 3) blootstelling aan prenatale risicofactoren voorspellend is voor fysiologische zelfregulatie in de babytijd. Deze bevindingen suggereren dat (preventieve) interventieprogramma’s ter voorkoming van agressief gedrag zich moeten richten op zowel beïnvloeden van prenatale omstandigheden als zelfregulatie in de vroege kindertijd. Show less
The current thesis focuses on the longitudinal development of early-adopted children in the 1887/29874 Leiden Longitudinal Adoption Study (LLAS). In the LLAS, adopted children were followed from... Show moreThe current thesis focuses on the longitudinal development of early-adopted children in the 1887/29874 Leiden Longitudinal Adoption Study (LLAS). In the LLAS, adopted children were followed from infancy until young adulthood. In Chapter 1 we discuss the role of sensitive parenting and the precursors and developmental outcomes of attachment security. In the empirical study in Chapter 2 we report on the concurrent as well as longitudinal relations between maternal sensitivity, child temperament, and externalizing behavior problems. In the second empirical study in Chapter 3, we follow this line of enquiry and investigate concurrent and longitudinal relations between maternal sensitivity, child temperament and internalizing behavior problems. Chapter 4 reports on the final empirical study of the thesis, and focuses on the associations between maternal sensitivity and attachment in infancy and the diurnal cortisol curve in young adulthood. Our empirical studies show that maternal sensitivity in infancy and middle childhood indirectly predicts fewer internalizing behavior problems in adopted adolescents, and that maternal sensitivity in adolescence predicts less concurrent delinquent behavior. Attachment experiences in early life do not predict the adoptees' diurnal cortisol curve in later life. In Chapter 5 we discuss these results and some methodological issues more thoroughly. Show less
The general objective of this thesis was to test the effectiveness of an early intervention program aimed at reducing externalizing problems in 1- to 3-year-old children by enhancing parental... Show moreThe general objective of this thesis was to test the effectiveness of an early intervention program aimed at reducing externalizing problems in 1- to 3-year-old children by enhancing parental sensitivity and adequate discipline strategies. A new intervention was designed for this study: the Video-feedback Intervention to promote Positive Parenting and Sensitive Discipline (VIPP-SD) The study consisted of a screening phase in a general population sample (N = 2408) and a randomized case-control intervention phase in a selected subsample of children with high levels of externalizing behavior problems (n = 237). The results of this thesis show that externalizing problems occur in children as young as 1 year of age and are moderately predictive of externalizing problems one year later. Furthermore, child temperament appears to be a moderator in the association between maternal discipline strategies and externalizing problems. Children with difficult temperaments are more susceptible to both negative discipline (i.e., showing more externalizing problems) and positive discipline (i.e., showing less externalizing problems) compared to children with relatively easy temperaments. Finally, the VIPP-SD intervention was effective in improving maternal attitudes towards sensitivity and sensitive discipline, enhancing actual maternal sensitive discipline practices, and decreasing the children's level of overactive behaviors. Show less