Infant Behavior & Development 33 (2010) 50–60 Contents lists available at ScienceDirect Infant Behavior and Development Maternal sensitivity throughout infancy: Continuity and relation to attachment security Ann E. Bigelow ∗ , Kim MacLean, Jane Proctor, Tanya Myatt, Rita Gillis, Michelle Power Department of Psychology, St. Francis Xavier University, Antigonish, Nova Scotia B2G 2W5, Canada article info Article history: Received 30 October 2008 Received in revised form 18 June 2009 Accepted 29 October 2009 Keywords: Maternal sensitivity Contingency Joint attention Attachment abstract Relations among different measures of maternal sensitivity were assessed longitudinally by examining maternal behavior when infants were 4 months, 15 months, and 2.5 years. At each time period, two measures of maternal sensitivity were scored (4 months: maternal vocal and smiling contingency in face-to-face interactions; 15 months: maternal scaffolding and following of infants’ play within joint attention; 2.5 years: maternal facilitative and collaborative play within joint attention). When infants were 2.5 years, attachment security was assessed. Mothers’ scores on each maternal sensitivity measure within each time period were correlated with their maternal sensitivity scores in another time period, suggesting individual measures of maternal sensitivity were tapping similar aspects across the time periods. Maternal vocal contingency at 4 months was the strongest predictor of infants’ attachment security over 2 years later. © 2009 Elsevier Inc. All rights reserved. Maternal sensitivity to infant behavior has been associated with a host of positive outcomes, the most noted of which is attachment (Ainsworth, Blehar, Waters, & Wall, 1978; DeWolff & van IJzendoorn, 1997; Meins, 1997; van den Boom, 1994); but other developments are also affected, such as self-efficacy (Bigelow, 1999; Jaffe, Beebe, Feldstein, Crown, & Jasnow, 2001), language acquisition (Tomasello & Farrar, 1986), and maturity of object play (Bigelow, MacLean, & Proctor, 2004). Behaviors judged to demonstrate maternal sensitivity are diverse, yet they are characterized by socially appropriate and relatively consistent responsiveness to infants’ signals and interactions that are within the infants’ zone of proximal development. Maternal sensitivity involves mothers’ ability to engage with infants at their level and current focus and to structure interactions to allow infants to achieve levels of development beyond those they could achieve on their own. Individual differences in maternal sensitivity are assumed to be stable over time, barring major stressful changes in life circumstances (Thompson, 1998). Ainsworth et al.’s (1978) seminal study of the antecedents of attachment security was one of the first to demonstrate relatively consistent maternal sensitivity across the infants’ first year of life. Subsequent studies using global ratings of maternal sensitivity, like those used by Ainsworth et al. (1978), have substantiated the importance of maternal sensitivity in early infancy for secure attachment at 1 year (Grossman, Grossman, Spangler, Suess, & Unzner, 1985; Isabella, 1993). However, studies that have sought to operationalize maternal sensitivity using observable indices of mother–infant interaction have found mixed results (Belsky & Isabella, 1988; Campos, Barrett, Lamb, Goldsmith, & Stenberg, 1983; Lamb, Thompson, Gardner, & Charnov, 1985), both in the relation between maternal sensitivity to attachment security and in the continuity of maternal behaviors. Yet the association between early maternal sensitivity and later positive infant outcomes suggests that individual dif- ferences in maternal sensitivity persist over time; that is, it is likely that the maternal behavior that indicates maternal ∗ Corresponding author at: Department of Psychology, St. Francis Xavier University, Box 5000, Antigonish, Nova Scotia B2G 2W5, Canada. Tel.: +1 902 867 3900; fax: +1 902 867 5189. E-mail address: abigelow@stfx.ca (A.E. Bigelow). 0163-6383/$ – see front matter © 2009 Elsevier Inc. All rights reserved. doi:10.1016/j.infbeh.2009.10.009