Exploring Infants’ Motor Activity: Attachment-Related Effects of Separation-Reunion on Locomotion and Object Engagement

• In Event: 1-093 - Understanding Motor Activity in Infants: The Role of Parent-Child Interaction

Integrative Statement

Introduction. According to attachment theory, stressful events activate contact seeking behavior, and suppress exploration. A recent study showed that exploratory behavior increases as infants develop crawling, which coincides with increased mother-infant interaction (Thurman & Corbetta, 2017). This indicates that both motor activity and mother-infant attachment are important factors for exploration. However, the connection between mother-infant attachment and exploratory motor activity has remained unclear. The aim of this study was to explore the relationship between attachment classification and patterns of locomotion and object engagement during separation-reunion.
Hypotheses. Separation was expected to decrease locomotion and object engagement. Securely attached infants were expected to show more object engagement and locomotion, compared to insecurely attached infants. Additionally, differences across attachment classifications were expected in duration of locomotion and object engagement as a function of separation and reunion.
Method. Infants and their mothers participated in a longitudinal birth cohort study. Out of 311 mother-infant dyads that visited the university to participate in the Strange Situation Procedure (SSP; Ainsworth, Blehar, Waters, & Wall, 1978), 135 dyads were quasi-randomly selected for the current study, ensuring at least 20 infants in each attachment category. Fifty-six infants were classified as secure, 24 as avoidant, 23 as resistant, and 32 as disorganized. Currently, motor activity data of 108 mother-infant dyads are available (52 girls; mean age 12.87 months, SD = 0.62), which will be completed to 135 dyads in the upcoming months. Infants’ motor activity was coded for type and duration of displacement and engagement with toys using a new real-time coding procedure in Noldus The Observer XT. Repeated measures analyses of variance were conducted to test whether the patterns of durations of displacement and object engagement across SSP episodes differed across attachment classification.
Results. Duration of object engagement significantly decreased during separation, and increased again at the second reunion with mother (Table 1; Figure 1A). Between-group comparisons showed that infants with insecure-resistant attachment showed less object engagement during the SSP than the other categories. Duration of displacement peaked during the second separation from mother. The pattern of duration of displacement significantly differed across attachment classifications. Duration of displacement decreased in insecure-resistant infants during the second reunion, but increased in insecure-avoidant infants, compared to secure and insecure-disorganized infants (Table 1; Figure 1B).
Discussion. The drop in object engagement during separation is consistent with the suppression of the exploratory behavior system under stress. Infants’ duration of displacement peaked during separation, consistent with locomotion serving both the attachment as well as exploratory behavior system. The consistently lower object engagement in insecure-resistant infants indicates that the setting of the SSP may already activate the attachment behavioral system or indicate more chronic under expression of exploration. Future research should elucidate whether infants’ motor activity during separation and reunion is an expression of the attachment and exploratory behavior system only, or whether it is also influenced by individual child characteristics, such as activity level.

Authors

• Lianne van Setten, Vrije Universiteit Amsterdam
  Presenting Author

• Annick Ledebt, Vrije Universiteit Amsterdam
  Non-Presenting Author

• Mirjam Oosterman, Vrije Universiteit Amsterdam
  Non-Presenting Author

• Geert J.P. Savelsbergh, Vrije Universiteit Amsterdam
  Non-Presenting Author

• Carlo Schuengel, Vrije Universiteit Amsterdam
  Non-Presenting Author

• Marleen HM De Moor, Child and Family Studies, Vrije Universiteit Amsterdam
  Non-Presenting Author