AbstractHandgrip force responses to infant signals were examined in a sample of 43 maltreating and 40 non-maltreating mothers. During a standardized handgrip paradigm, mothers were asked to squeeze... Show moreAbstractHandgrip force responses to infant signals were examined in a sample of 43 maltreating and 40 non-maltreating mothers. During a standardized handgrip paradigm, mothers were asked to squeeze a handgrip dynamometer at maximal and at half of their maximal handgrip strength while listening to infant crying and laughter sounds. Maltreating mothers used excessive force more often while listening to infant crying and laughter than non-maltreating mothers. Of the maltreating mothers, only neglectful mothers (n = 20) tended to use excessive force more often during crying than non-maltreating mothers. Participants did not rate the sounds differently, indicating that maltreating mothers cannot be differentiated from non-maltreating mothers based on their perception of infant signals, but show different behavioral responses to the signals. Results imply that, in response to infant signals (i.e., crying or laughing), maltreating mothers may be insufficiently able to regulate the exertion of physical force. Show less
In this thesis the development, stability, and correlates of early childhood aggression were investigated. The normative development was examined in a general population sample using questionnaires... Show moreIn this thesis the development, stability, and correlates of early childhood aggression were investigated. The normative development was examined in a general population sample using questionnaires completed by the parents of 12-, 24-, and 36-month-old children and again one year later. Results showed an early childhood aggression curve, with increasing rates of aggression in the second year of life and decreasing rates in the fourth year. One-year stabilities were moderate for 12-month-olds and high for 24- and 36-month-olds. In a subsample of mother-child dyads child physical aggression and parenting were observed from videotapes recorded when the children were 1-3 years old and again one year later. Results indicated that negative discipline was positively related to child aggression one year later, but only when mothers were low in initial sensitivity. Finally, a meta-analysis of the literature showed that basal cortisol levels are positively related to aggression in preschoolers, but that this relation is reversed in school-aged children. The association is stronger in children with clinical levels of problem behavior. This study sheds light on the normative course of early childhood aggression and its physiological and parental correlates. Show less
Alink, L.R.A.; Mesman, J.; Zeijl, J. van; Stolk, M.N.; Juffer, F.; Koot, H.M.; ... ; IJzendoorn, M.H. van 2006
