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
Wijk, I.C. van; Huffmeijer, R.; Bosdriesz, J.R.; Bakermans-Kranenburg, M.J.; Kolijn, L.; Van IJzendoorn, M.H.; ... ; Bulk, B.G. van den 2019
Both social perception and temperament in young infants have been related to social functioning later in life. Previous functional Near-Infrared Spectroscopy (fNIRS) data (Lloyd-Fox et al., 2009)... Show moreBoth social perception and temperament in young infants have been related to social functioning later in life. Previous functional Near-Infrared Spectroscopy (fNIRS) data (Lloyd-Fox et al., 2009) showed larger blood-oxygenation changes for social compared to non-social stimuli in the posterior temporal cortex of five-month-old infants. We sought to replicate and extend these findings by using fNIRS to study the neural basis of social perception in relation to infant temperament (Negative Affect) in 37 five-to-eight-month-old infants.Infants watched short videos displaying either hand and facial movements of female actors (social dynamic condition) or moving toys and machinery (non-social dynamic condition), while fNIRS data were collected over temporal brain regions. Negative Affect was measured using the Infant Behavior Questionnaire.Results showed significantly larger blood-oxygenation changes in the right posterior-temporal region in the social compared to the non-social condition. Furthermore, this differential activation was smaller in infants showing higher Negative Affect.Our results replicate those of Lloyd-Fox et al. and confirmed that five-to-eight-month-old infants show cortical specialization for social perception. Furthermore, the decreased cortical sensitivity to social stimuli in infants showing high Negative Affect may be an early biomarker for later difficulties in social interaction. 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
Between 10 and 14 months, infants gain the ability to learn about unfamiliar stimuli by observing others’ emotional reactions to those stimuli, so called social referencing (SR). Joint processing... Show moreBetween 10 and 14 months, infants gain the ability to learn about unfamiliar stimuli by observing others’ emotional reactions to those stimuli, so called social referencing (SR). Joint processing of emotion and head/gaze direction is essential for SR. This study tested emotion and head/gaze direction effects on infants’ attention via pupillometry in the period following the emergence of SR. Pupil responses of 14-to-17-month-old infants (N = 57) were measured during computerized presentations of unfamiliar objects alone, before-and-after being paired with emotional (happy, sad, fearful vs. neutral) faces gazing towards (vs. away) from objects. Additionally, the associations of infants’ temperament, and parents’ negative affect/depression/anxiety with infants’ pupil responses were explored. Both mothers and fathers of participating infants completed questionnaires about their negative affect, depression and anxiety symptoms and their infants’ negative temperament. Infants allocated more attention (larger pupils) to negative vs. neutral faces when the faces were presented alone, while they allocated less attention to objects paired with emotional vs. neutral faces independent of head/gaze direction. Sad (but not fearful) temperament predicted more attention to emotional faces. Infants’ sad temperament moderated the associations of mothers’ depression (but not anxiety) with infants’ attention to objects. Maternal depression predicted more attention to objects paired with emotional expressions in infants low in sad temperament, while it predicted less attention in infants high in sad temperament. Fathers’ depression (but not anxiety) predicted more attention to objects paired with emotional expressions independent of infants’ temperament. We conclude that infants’ own temperamental dispositions for sadness, and their exposure to mothers’ and fathers’ depressed moods may influence infants’ attention to emotion-object associations in social learning contexts. 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
