Do infant behaviors following immunization predict attachment? An ...

ATTACHMENT & HUMAN DEVELOPMENT, 2016 VOL. 18, NO. 1, 90–99 http://dx.doi.org/10.1080/14616734.2015.1115113

Do infant behaviors following immunization predict attachment? An exploratory study Rachel Hortona, Rebecca Pillai Riddella,b,c, Greg Morand and Diana Lisia a

Psychology, York University, Toronto, Canada; bPsychology, Hospital for Sick Children, Toronto, Canada; Psychology, University of Toronto, Toronto, Canada; dOffice of the Provost, Aga Khan University, Nairobi, Kenya c

ABSTRACT

ARTICLE HISTORY

Objectives. The relationship between infant behaviors during routine immunization, pre- and post-needle, and infant attachment was explored. Methods. A total of 130 parent–infant dyads were recruited from a larger longitudinal study and videotaped during routine immunization at 12 months and the Strange Situation Procedure (SSP) at 14 months. Six infant behaviors were coded for 1-minute pre-needle and 3-minutes post-needle. Attachment was operationalized according to the secure/avoidant/resistant/disorganized categories. Results. As expected, none of the pre-needle behaviors predicted attachment. Proximity-seeking post-needle significantly discriminated attachment categorizations. Secure infants were more likely to seek proximity to caregivers post-needle in comparison with avoidant and disorganized infants. Proximity-seeking following immunization was positively correlated with proximityseeking during the SSP and negatively correlated with avoidance and disorganization during the SSP. Conclusions. Infant proximityseeking during immunization is associated with attachment security and parallels behaviors observed during the SSP. More research is needed to identify behavioral markers of disorganization.

Received 9 November 2014 Revised 28 October 2015 Accepted 28 October 2015 KEYWORDS

pain; attachment; infancy; affect regulation; immunization

Infant distress is present at virtually all pediatric immunization appointments (Pillai Riddell et al., 2013). The presence of distress and infants’ reliance on caregivers to regulate this distress suggests that immunization appointments may provide a generally standardized and ecologically valid paradigm in which to understand infant attachment. In turn, health care professionals could potentially screen for attachment challenges within the context of routine healthcare visits. One way to make universal primary health care screening of attachment challenges a reality is to identify readily understood immunization behaviors that are validly and reliably associated with attachment. In Mary Ainsworth’s pioneering research (Ainsworth, Blehar, Waters, & Wall, 1978), reunion behavior after separation-related distress was the key determinant of the quality of attachment. Infants efforts to seek proximity and contact with caregivers following a brief separation was seen as of particular importance to determining attachment. Within the Strange Situation Procedure (SSP), secure infants actively seek proximity and contact CONTACT Rebecca Pillai Riddell © 2015 Taylor & Francis

[email protected]

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with their caregivers upon reunion in order to effectively regulate distress (Cassidy, 1994), while avoidant infants are more likely to evade proximity and contact with caregivers. Similar to secure infants, resistant infants actively seek proximity and contact with caregivers upon reunion; however, these infants heighten behavioral distress when in contact with caregivers and appear ambivalent about proximity (e.g., fussing and pushing away from caregivers). Later, Mary Main and colleagues further noted that the proximity-seeking and contact-seeking behavior of disorganized infants following reunion was atypical and contradictory (e.g., freezing, turning in circles), as these infants were seen to have no organized strategy for regulating distress in the presence of the caregiver (Beebe et al., 2012). Using these basic templates for understanding attachment within the laboratory setting, a number of researchers have examined associations between infant behavior and attachment during primary care visits. Gunnar, Brodersen, Nachmias, Buss, and Rigatuso (1996) found that infants’ behavioral distress to immunization was not associated with attachment; however, the authors examined infant crying exclusively and did not examine other attachment-related behaviors (e.g., proximity- and contact-seeking) that may differ as a function of attachment security. Favez and Berger (2011) introduced a new qualitative tool, the Paediatric Attachment Style Indicator (PASI), in their study on attachment of infants in the immunization context. While promising findings were reported, the results were limited by a small sample. Wolff and colleagues (2011) examined whether infant distress during venipuncture predicted attachment using the secure/insecure and organized/disorganized two-level comparisons. Infant distress did not predict attachment, however, the authors combined distress behaviors (e.g., crying, information-seeking) into one variable, omitting an examination of individual behaviors, such as proximity- and contact-seeking, that are theoretically related to attachment in different ways. Given that proximity- and contact-seeking behaviors are critical determinants of attachment, it would behoove researchers to focus on these behaviors in the pediatric primary care setting. Moreover, research is needed that includes larger samples and, although statistically useful to use the two-level comparisons of attachment (i.e., secure/ insecure; organized/disorganized), the four-level comparison (i.e., secure/avoidant/resistant/disorganized) is likely to shed light on important differences within the insecure or organized groups (e.g., avoidant infants evade proximity while resistant infants actively seek proximity to caregivers).

The current study We sought to determine whether specific infant behaviors, particularly proximity- and contact-seeking behavior, exhibited during immunization predict attachment. Mother– infant dyads belonging to the Opportunities to Understand Childhood Hurt (OUCH) Cohort (Pillai Riddell et al., 2011) were invited to participate in a laboratory-based attachment study at the local children’s hospital following their 12-month immunization. The OUCH Cohort now comprises 760 infants and their caregivers who have been followed longitudinally in order to gain a better understanding of pain in childhood, parent and child interactions during painful procedures, and methods that parents and professionals can use to help soothe children in pain. Of 286 caregivers approached at the 12-month appointment at the time of this study, 175 (62%) agreed to participate. Due to scheduling difficulties, some caregivers were unable to bring their infants to the

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hospital prior to 18 months of age (the upper age limit for the SSP). The final sample consisted of 130 dyads. Infant behavior during the 12-month immunization and the infant’s attachment status at 14 months were examined. The main research question was whether infant behaviors exhibited during the routine pediatric visit at 12 months were related to attachment in theoretically predictable ways. Attachment was operationalized using the four-level comparison (secure/avoidant/ resistant/disorganized). Behaviors were examined pre- and post-needle, so as to distinguish between the phase prior to the painful stimulus and following the painful stimulus. It was hypothesized that infant behaviors exhibited pre-needle would not be associated with attachment because the infants would not be significantly distressed prior to immunization and, thus, it would not be an attachment-eliciting context. Infant behaviors exhibited post-needle were hypothesized to be associated with attachment, as they would occur in response to immunization, a distress-provoking stimulus that is expected to trigger attachment behavior.

Methods Participants and procedures Participants were recruited from a larger longitudinal study of infant–caregiver dyads in the Greater Toronto Area that followed infants and caregivers longitudinally at the 2-, 4-, 6- and 12-month well-baby appointments. Eligibility criteria for the larger study required that infants were healthy and born at >37 weeks gestation, had no developmental delays or neurological impairments, had never stayed in a neonatal intensive care unit, and had parents who were fluent in English (in order to complete consent and study questionnaires). A full description of the OUCH cohort procedure appears elsewhere (e.g., Pillai Riddell et al., 2011). The immunization appointment was videotaped by a research assistant (RA) using two cameras. One camera focused on the infant’s behaviors while the other camera captured both infant and caregiver. Caregivers and infants were approached at their routine 12-month well-baby appointment and were asked if they were interested in taking part in a study at the local children’s hospital when their infant was between 12 and 18 months of age, in order to take part in the SSP. If both parents attended the appointment, the parent who was primarily responsible for the infant (defined as the parent who spent the most time with the infant) was asked to attend the attachment appointment at the hospital. Caregivers who agreed to participate filled out an additional set of consent forms at the hospital, as well as other demographic and infant behavioral questionnaires. Families received CAD$10 to assist with the cost of travel and parking, an infant onesie, and a photo of their infant. The laboratory visit at the hospital was recorded with two wallmounted video cameras. The experimental room included a one-way mirror for the researcher to observe the participants (the caregiver, infant, and a RA who acted as the stranger), two chairs, and age-appropriate toys. A total of 130 dyads made up the final sample, including 72 male infants and 58 female infants. Of the primary caregivers who attended the SSP, 89% were mothers. At the time of the SSP, infants were an average age of 13.74 months (SD = 1.35) and

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the average age of caregivers was 34.70 years (SD = 5.05). The majority of parents were well educated (76% had obtained at least a university degree) and were married or in common-law relationships (94%). Self-reported heritage culture indicated the sample was 44% European, 20% Canadian/American, 11% Asian, 6% Central American/Caribbean, 6% South Asian, 5% South American and 5% African/Middle Eastern.

Measures Infant behaviors Prior to the beginning of the study, a selection of infant behaviors was identified that were expected to be associated with different attachment classifications. In order to select the behaviors, the four scales of the Scoring System for Interactive Behaviors (SSIB; Ainsworth et al., 1978) that is used to code behaviors observed during the SSP were utilized: (1) Proximity- and Contact-Seeking; (2) Contact-Maintaining; (3) Resistant; and (4) Avoidant. There were 17 infant behaviors initially considered, but through consensus methodology between three of the authors (RH, RPR and GM), pilot testing on 20 video clips (not used in the current study), and preliminary reliability coding with four independent coders, six commonly-occurring infant behaviors during pediatric visits at 12 months were selected for the present study: proximity-seeking (initiating close body contact with the caregiver), reaching towards caregiver (arms outstretched towards caregiver), clinging to caregiver (fists clenched around caregiver’s clothing, body, or hair), back arch/pushes away (arching back when distressed/pushing away from the caregiver with arms or legs), arm(s) between self and caregiver (placing stiff arms between the self and caregiver), and cry/grimace (expressions of discomfort including crying and grimacing). Proximity-seeking and reaching towards caregiver behaviors map onto the Proximityand Contact-Seeking scale of the SSIB, clinging to caregiver maps onto the ContactMaintaining scale of the SSIB, back arch/pushes away maps onto the Resistant scale of the SSIB, and arm(s) between self and caregiver maps onto the Avoidant scale of the SSIB. Cry/grimace was measured in order to determine whether the amount of distress expressed varied according to attachment. Previous research has shown that, among older children (approximately five years of age), avoidant and disorganized attachment is associated with greater reactions to pain, both in the pediatric and home settings, and disorganization is associated with longer recovery from pain (Walsh, McGrath, & Symons, 2008). Intraclass correlations on the final coding system both pre- and post-needle were high (.80 to 1.00) with the exception of arm(s) between self and caregiver pre-needle, which was acceptable (.69) (see Table 1). Behaviors were coded as present (1) or absent (0) for every five seconds of four 60second epochs (1-minute pre-needle, and 1-, 2-, and 3-minutes post-needle). Average epoch scores were calculated for each behavior pre- and post-needle (see Table 2). Preand post-needle scores ranged from 0 to 1.00, representing the proportion of time spent exhibiting the behavior. Cry/grimace was coded on a 0 to 3 scale based on the intensity of the infant’s distress, and the average score was used in analyses.

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Table 1. Reliability intraclass correlation coefficients for infant behaviors. Infant behavior

Coders Pre-Needle PC and C1 PC and C2 PC and C3 C1 and C2 C1 and C3 C2 and C3 Post-Needle PC and C1 PC and C2 PC and C3 C1 and C2 C1 and C3 C2 and C3

n

Reaching towards caregiver

Proximityseeking

Clinging to caregiver

Back arch/ pushes away

Arm(s) between self and caregiver

Cry/ grimace

34 34 15 34 15 15

.92 .93 1.00 .82 .95 .90

.97 .96 .98 .91 .98 .97

.99 .93 .99 .91 .99 .98

1.00 1.00 1.00 1.00 1.00 1.00

.99 .69 .95 .98 .98 .88

.98 .97 .99 .97 .99 .99

34 34 15 34 15 15

.92 .95 .91 .94 .96 .92

.98 .90 .96 .95 .94 .95

.99 .90 .99 .98 .99 .98

.93 .91 .94 .95 .97 .98

.99 .98 .97 .98 .98 .98

.98 .90 .98 .93 .99 .93

Note: PC = Primary Coder, C1 = Coder 1, C2 = Coder 2, C3 = Coder 3.

Table 2. Means and standard deviations of infant behaviors pre- and post-needle according to attachment. Avoidant (A)

Reach P-S Cling BA/ PA Arm(s) B Cry/G

Secure (B)

Resistant (C)

Disorganized (D)

Pre-

Post-

Pre-

Post-

Pre-

Post-

Pre-

Post-

n = 31 .03 (.07) .02 (.07) .45 (.36) – .05 (.15) 1.09 (.22)

n = 31 .03 (.05) .09 (.15) .59 (.28) .01 (.02) .08 (.14) 1.93 (.44)

n = 68 .03 (.09) .09 (.19) .55 (.38) – .08 (.21) 1.27 (.44)

n = 66 .02 (.04) .25 (.29) .64 (.30) .01 (.04) .07 (.16) 1.98 (.50)

n=8 .01 (.03) .04 (.08) .47 (.44) – .10 (.26) 1.23 (.22)

n=7 .04 (.04) .25 (.29) .64 (.33) .01 (.01) .06 (.12) 2.11 (.31)

n = 23 .01 (.03) .07 (.15) .56 (.40) – .08 (.19) 1.25 (.41)

n = 22 .03 (.06) .11 (.16) .58 (.30) .01 (.02) .05 (.10) 1.96 (.38)

Note: Reach = Reaching towards caregiver, P-S = Proximity-Seeking, Cling = Clinging to caregiver, BA/PA = Back arch/ pushes away, Arm(s) B = Arm(s) between self and caregiver, Cry/G = Cry/grimace. Back arch/pushes away pre-needle was dropped from analyses as more than 90% of infants did not exhibit this behavior.

Infant–caregiver attachment Validated by over 30 years of research, the SSP (Ainsworth et al., 1978) is considered the gold standard measure of attachment in infancy. Attachment is assessed over eight episodes, which involve a series of separations and reunions between the infant and caregiver, as well as a visit from a “stranger”. The Indices of Disorganization and Disorientation (Main & Solomon, 1990) is used to identify disorganized attachment (denoted by the letter D). The Scoring System for Interactive Behaviors (SSIB; Ainsworth et al., 1978) described above is used to code interactive behaviors between the infant and caregiver during episode 5 and 8, when infant and caregiver are reunited after a brief separation. A reliable and experienced coder from a research laboratory at the University of Western Ontario coded the entire sample, including the disorganized classifications. About 71% of all cases (n = 92) were double coded for reliability, with acceptable to excellent reliability scores ranging from .75 to 1.00 (see Table 3).

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Table 3. Intraclass correlation coefficients for SSP reliability. Coders

N

A/B/C/D

PC and C1 PC and C2 C1 and C2

68 24 7

.75 .80 .93

Note: PC = Primary Coder, C1 = Coder 1, C2 = Coder 2, C3 = Coder 3.

Of the total sample of 130 infants, 24% were classified as avoidant, 52% were classified as secure, 6% were classified as resistant, and 18% were classified as disorganized, consistent with attachment distributions in previous studies (Ainsworth et al., 1978; Main & Solomon, 1990; van Ijzendoorn, Schuengel, & Bakermans-Kranenburg, 1999).

Results Initial correlational analyses More than 90% of infants did not exhibit the back arch/pushes away behavior pre-needle and it was therefore not included in subsequent pre-needle analyses. Missing data was present in four cases post-needle and they were therefore excluded from the postneedle analyses. Exploratory Pearson correlations were performed for each of the behaviors pre- and postneedle and the interactive behavior scales of the SSP. None of the pre-needle behaviors were associated with interactive behaviors in either episode 5 or episode 8 of the SSP. Proximity-seeing post-needle was correlated with the Proximity- and Contact-Seeking, r (117) = .22, p < .05, and the Avoidance, r(116) = −.22, p < .05, scales of the SSIB during episode 8 (the reunion episode) of the SSP. The relationship between proximity-seeking postneedle and disorganization during the SSP approached significance, r(123) = −.18, p = .050.

Primary analyses A total of 11 logistic regressions were performed in order to explore whether any of the five pre-needle behaviors or the six post-needle behaviors predicted attachment. None of the pre-needle behaviors (proximity-seeking, reaching towards caregiver, clinging to caregiver, arm(s) between self and caregiver, and cry/grimace) significantly predicted attachment. Of the six infant behaviors post-needle (proximity-seeking, reaching towards caregiver, clinging to caregiver, back arch/pushes away, arm(s) between self and caregiver, and cry/ grimace), only proximity-seeking was a significant predictor of attachment, χ2 (3) = 13.13, p = .004, such that a greater proportion of time spent in proximity-seeking behavior resulted in a higher likelihood that an infant would be classified as secure. Secure infants engaged in proximity-seeking significantly more than avoidant (β = −3.61, χ2 (3) = 6.50, p = .01) and disorganized (β = −2.78, χ2 (3) = 3.93, p = .047; trend) infants. There was no significant difference between secure and resistant groups with respect to proximityseeking behavior (see Table 4).

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Table 4. Results from regression analyses. Pre-Needle (n = 130) Reaching towards caregiver Proximity-Seeking Clinging to caregiver Back arch/pushes away Arm(s) between self and caregiver Cry/grimace

Post-Needle (n = 126)

χ2

df

p

χ2

df

p

2.49 6.045 1.805 – .877 5.826

3 3 3 – 3 3

.48 .12 .61 – .83 .12

1.810 13.130 1.095 1.589 .615 .956

3 3 3 3 3 3

.61 .004* .61 .662 .89 .81

* p ≤ .01

Discussion This is the first study, to our knowledge, to empirically demonstrate how specific infant behaviors during routine immunization at 12 months are associated with attachment using the four-level comparison of secure, avoidant, resistant, and disorganized in a relatively larger sample. Consistent with hypotheses, none of the behaviors exhibited pre-needle predicted attachment. We had speculated that the general absence or low-level expression of infant distress pre-needle would suggest that the pre-needle phase would be less likely to trigger the attachment system and that these behaviors should not be associated with attachment. Moreover, correlational analyses revealed that none of the pre-needle behaviors were associated with interactive behaviors during the SSP. Proximity-seeking post-needle, however, was positively associated with the Proximity- and Contact-Seeking scales of the SSIB during the reunion episode (i.e., episode 8) of the SSP. These findings suggest that infants’ efforts to actively seek proximity to their caregivers represent attachment-driven behaviors that are relative stable across contexts that elicit distress; infants who activity seek proximity to caregivers following an immunization are also more likely to seek proximity to caregivers following separation. Moreover, proximity-seeking post-needle was negatively associated with the Avoidance scale of the SSIB during episode 8 of the SSP, and a negative relationship between proximity-seeking post-needle and disorganization during the SSP approached significance. Given that proximity-seeking behavior post-needle differentiated secure from disorganized and avoidant infants, these correlational findings are not surprising. Infants who are secure are more likely to seek close physical proximity with their caregivers in comparison with disorganized and avoidant infants. Ainsworth and her colleagues characterized proximity-seeking as a secure-base behavior (Ainsworth et al., 1978) that should theoretically be activated during times of distress, and our study lends support to attachment theory in this regard. Consistent with hypotheses that secure infants would display more proximity- and contact-seeking behavior, proximity-seeking was a significant predictor of secure attachment post-needle, such that infants who sought proximity to caregivers were more likely to be classified as secure than avoidant or disorganized. This finding supports attachment theory in that the attachment system appears to be triggered following a painful stimulus and secure infants actively use their caregivers to help them to regulate distress by initiating close physical contact with them. As expected, avoidant and disorganized infants were less likely than their secure counterparts to seek physical comfort from

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caregivers. Taken together, these findings underscore the utility of the primary care setting as a context in which to gain insight into the caregiver–infant attachment relationship. Our results highlight proximity-seeking as a significant marker of attachment in distress-provoking situations other than the SSP. It should be emphasized that proximityseeking was coded only when the infant initiated physical proximity to the caregiver (i.e., the infant actively snuggled into the caregiver’s body with her head or body), and was not coded when the caregiver initiated contact with the infant. The findings of this study suggest that, by one-year-old, infants’ active attempts to gain close physical contact with their primary caregivers are reflective of the nature of the attachment relationship. There are limitations to the study that warrant note. At this exploratory stage of understanding attachment in a medical context, it is noteworthy that resistant infants were not distinguishable from secure infants based on the behaviors observed. Given the short period of analysis (three minutes) and the prolonged pain stimulus (i.e., the pain from the needle continues for minutes and potentially hours post-needle), it is plausible that behavioral differences between secure and resistant infants emerge over a longer post-needle period. It is likely that secure and resistant infants are indistinguishable in the short-period following a painful stimulus because both groups would be expected to continue signaling their caregivers for proximity. However, while the secure infant is expected to effectively use proximity to the caregiver to regulate distress, the resistant infant is expected to have difficulty regulating distress, resulting in a longer period of distress regulation. Longer periods of distress regulation have been noted in older children with a disorganized attachment style (Walsh et al., 2008), and it would be important for researchers to extend the observation of behaviors beyond the threeminute post-needle period, until all infants have returned to baseline levels of nondistress. Furthermore, as there were only eight resistant infants in our sample, limited power substantiates the need for studies that include a greater number of resistant infants. Although findings from this study provide some insight into the attachment-related behaviors of infants following immunization, more work is needed to understand the complex interplay between parent and child factors on various health outcomes. For example, a recent study using this sample found that attachment and temperament interact to predict infants’ regulation of distress (Horton, Pillai Riddell, Flora, Moran, & Pederson, 2015). Temperament was not included in the current study, but may elucidate some of the relationships between behaviors in the pediatric setting and behavior during the SSP. Another important focus for future research is the need to identify distinct behavioral markers of disorganization during pediatric appointments, as this group is the most vulnerable with respect to physical and mental health outcomes. Similar to contradictory behavior observed during the SSP, sequences of contradictory behavior during the pediatric visit (such as strong proximity-seeking followed by strong avoidant or freezing behavior) may be more robustly related to disorganization than the frequency of behaviors observed. Further research is needed in this regard. Given that our sample was a relatively low-risk sample with high levels of parental education, further research is needed with high-risk samples. Finally, due to scheduling difficulties, 45% of parents approached to participate in the study ultimately participated, and the possibility of a selection bias should be considered.

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Conclusions and clinical implications The findings of this study suggest that behaviors observed in the pediatric setting following immunization, specifically proximity-seeking behavior, are associated with the infant–caregiver attachment relationship. This finding substantiates the potential for future research to determine feasible and valid ways to screen for infant mental health during routine well-baby visits. More research is needed to expand on our analysis of predictive behaviors of infant mental health during well-baby visits, particularly with respect to behaviors that are associated disorganized relationships.

Acknowledgments The authors thank the staff at the pediatric clinics and the Hospital for Sick Children for their assistance with this project. This work could not have been completed without the dedicated support, mentorship, and expertise of Sandi Bento and Dr. David Pederson. The authors are grateful to the OUCH cohort families for their participation and continued support over the years.

Disclosure statement No potential conflict of interest was reported by the authors.

Funding This work was supported by the Canadian Institutes of Health Research through a New Investigator salary award and operating grant [grant number MOP84511], Canadian Institutes of Health Research Pain in Child Health Strategic Training Program [grant number MOP111140], Ontario Ministry of Research and Innovation Early Researcher Award program [grant number ER0805-219], Ontario Graduate Scholarship Program, The York Research Chairs Program, and York University’s Lillian Wright Maternal–Child Health Scholarship program.

References Ainsworth, M. D. S., Blehar, M., Waters, E., & Wall, S. (1978). Patterns of attachment: A psychological study of the strange situation. Hillsdale, NJ: Erlbaum. Beebe, B., Lachmann, F. M., Markese, S., Buck, K. A., Bahrick, L. E., Chen, H., . . . Jaffe, J. (2012). On the origins of disorganized attachment and internal working models: Paper II. An empirical microanalysis of 4-month mother-infant interaction. Psychoanalytic Dialogues, 22, 352–374. doi:10.1080/10481885.2012.679606 Cassidy, J. (1994). Emotion regulation: Influences of attachment relationships. Monographs of the Society for Research in Child Development, 59(2/3), 228–249. doi:10.2307/1166148 Favez, N., & Berger, S. (2011). Mother-toddler attachment in a paediatric setting: Presentation and validation of the paediatric attachment style indicator. European Journal of Developmental Psychology, 8(5), 587–607. doi:10.1080/17405629.2011.590648 Gunnar, M. R., Brodersen, L., Nachmias, M., Buss, K., & Rigatuso, J. (1996). Stress reactivity and attachment security. Developmental Psychobiology, 29(3), 191–204. doi:10.1002/(ISSN)1098-2302 Horton, R. E., Pillai Riddell, R., Flora, D., Moran, G., & Pederson, D. (2015). Distress regulation in infancy: Attachment and temperament in the context of acute pain. Journal of Developmental & Behavioral Pediatrics, 36(1), 35–44. doi:10.1097/DBP.0000000000000119 Main, M., & Solomon, J. (1990). Procedures for identifying infants as disorganized/disoriented during the Ainsworth strange situation. In M. T. Greenberg, D. Cicchetti, & E. M. Cummings

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(Eds.), Attachment in the preschool years: Theory, research and intervention (pp. 121–160). Chicago. IL: The University of Chicago Press. Pillai Riddell, R., Campbell, L., Flora, D., Racine, N., Din Osmun, L., Garfield, H., & Greenberg, S. (2011). The relationship between caregiver sensitivity and infant pain behaviors across the first year of life. Pain, 152(12), 2819–2826. doi:10.1016/j.pain.2011.09.011 Pillai Riddell, R., Flora, D. B., Stevens, S. A., Stevens, B., Cohen, L. L., Greenberg, S., & Garfield, H. (2013). Variability in infant acute pain responding meaningfully obscured by averaging pain responses. Pain, 154(5), 714–721. doi:10.1016/j.pain.2013.01.015 van Ijzendoorn, M. H., Schuengel, C., & Bakermans-Kranenburg, M. J. (1999). Disorganized attachment in early childhood: Meta-analysis of precursors, concomitants, and sequelae. Development and Psychopathology, 11(2), 225–250. doi:10.1017/S0954579499002035 Walsh, T. M., McGrath, P. J., & Symons, D. K. (2008). Attachment dimensions and young children’s response to pain. Pain Research and Management, 13(1), 33–40. Wolff, N. J., Darlington, A. E., Hunfeld, J. A. M., Tharner, A., van Ijzendoorn, M. H., BakermansKranenburg, M. J., . . . Tierneier, H. (2011). The influence of attachment and temperament on venipuncture distress in 14-month-old infants: The generation R study. Infant Behavior and Development, 34(2), 293–302. doi:10.1016/j.infbeh.2011.01.005