Child maltreatment severity and sleep variability predict mother–infant RSA coregulation

Regulatory processes underlie mother-infant interactions and may be disrupted in adverse caregiving environments. Child maltreatment and sleep variability may reflect high-risk caregiving, but it is unknown whether they confer vulnerability for poorer mother–infant parasympathetic coordination. The aim of this study was to examine mother–infant coregulation of respiratory sinus arrhythmia (RSA) in relation to child maltreatment severity and night-to-night sleep variability in 47 low-income mother–infant dyads. Maternal and infant sleep was assessed with actigraphy and daily diaries for 7 nights followed by a mother–infant still-face procedure during which RSA was measured. Higher maltreatment severity was associated with weakened concordance in RSA coregulation related to the coupling of higher mother RSA with lower infant RSA, suggesting greater infant distress and lower maternal support. In addition, higher infant sleep variability was associated with infants’ lower mean RSA and concordance in lagged RSA coregulation such that lower maternal RSA predicted lower infant RSA across the still-face procedure, suggesting interrelated distress. The findings indicate that adverse caregiving environments differentially impact regulatory patterns in mother–infant dyads, which may inform modifiable health-risk behaviors as targets for future intervention.

P012 Maternal and infant stress during a bedtime separation: a pilot RCT

Background Behavioural sleep interventions to improve infant sleep disturbance commonly include extinction where an unwanted behaviour (night time crying) is periodically ignored. There have been conflicting findings regarding the impact of extinction methods on infant stress levels as measured with cortisol and as perceived by mothers and only one that measured cortisol at the time of the separation. This study aimed to compare a responsive method to extinction (controlled crying) and a control group evaluating subjective and objective stress for mother/infant dyads at the time of bedtime separation. Methods Mother/infant dyads were randomly allocated to behavioural sleep interventions (Responsive - n= 7, Controlled Crying - n=6 or Controls - n=4). Cortisol (two oral swabs on two nights at T2), maternal self-reported stress (Subjective Units of Distress - SUDS), and perceived infant distress (PIS) were compared over eight weeks. Correlations tested relationships between PIS, SUDS and infant cortisol levels. Mixed models analysis were used for cortisol analyses. Results There were no significant differences in cortisol levels between groups across time points but significant inter and intra-individual variability. Maternal stress was positively correlated with infant cortisol and PIS (p<0.05) and mothers in the Responsive group were significantly less stressed (p=0.02). Conclusion In this small sample, infant cortisol during bedtime separation was variable, elevated in all sleep interventions and not significantly different. Mothers were less stressed in the Responsive group. Findings indicate responsive methods are comparable to extinction and less stressful for mothers offering a possible gentler choice at bedtime separation.

Emotion regulation in infants using maternal singing and speech

The interaction between a mother and her infant has been described as an intricate ‘dance’ involving coordinated singing and movement (Feldman, 2007). It is widely accepted that infant-directed (ID) speech, characterized as having higher pitch, slower tempo, and exaggerated intonation, is an effective means of communicating with infants and holding their attention (Papousek et al., 1985). Singing is another universally observed caregiving behaviour. Mothers across cultures intuitively use infant-directed (ID) singing to regulate their infants’ emotional state (de l’Etoile, 2006; Nakata & Trehub, 2004). While ID speech and singing appear to be equally successful in regulating infants’ attention (Corbeil, et al., 2013), their effects in modulating infants’ distress are less clear. More precisely, while stress and arousal are intimately connected, there is no research to date that has investigated the efficacy of speech and singing in alleviating infant distress. Using a modified version of the Face-to-Face/Still-Face (FFSF) paradigm (Tronick et al., 1978), the current study is the first to examine 10-month-old infants’ behavioural and physiological responses, via Skin Conductance (SC), to their mother’s singing and speaking. Stress was effectively induced in the still-face episode with infants exhibiting typical “still-face” behaviours and elevated SC responses. The results indicated that in the reunion episode, mother’s singing was more effective in decreasing infant’s physiological arousal, regulating negative affect and promoting infants’ visual attention in comparison to maternal speaking. However, the genre of songs selected (e.g., play song or lullaby) might have been contributed to the positive outcomes of singing in regulating infants’ emotions. Therefore, the second study used the same methodology to examine the effects of maternal play songs and lullabies on infants’ physiological and behavioural responses. The results indicated that maternal play songs were more effective in regulating infants’ stress as well as capturing and maintaining their attention than were soothing lullabies. Taken together, the findings indicate that maternal singing, specifically playful performances, supports infants’ emotions and effectively regulates their stress.

Emotion regulation in infants using maternal singing and speech

The interaction between a mother and her infant has been described as an intricate ‘dance’ involving coordinated singing and movement (Feldman, 2007). It is widely accepted that infant-directed (ID) speech, characterized as having higher pitch, slower tempo, and exaggerated intonation, is an effective means of communicating with infants and holding their attention (Papousek et al., 1985). Singing is another universally observed caregiving behaviour. Mothers across cultures intuitively use infant-directed (ID) singing to regulate their infants’ emotional state (de l’Etoile, 2006; Nakata & Trehub, 2004). While ID speech and singing appear to be equally successful in regulating infants’ attention (Corbeil, et al., 2013), their effects in modulating infants’ distress are less clear. More precisely, while stress and arousal are intimately connected, there is no research to date that has investigated the efficacy of speech and singing in alleviating infant distress. Using a modified version of the Face-to-Face/Still-Face (FFSF) paradigm (Tronick et al., 1978), the current study is the first to examine 10-month-old infants’ behavioural and physiological responses, via Skin Conductance (SC), to their mother’s singing and speaking. Stress was effectively induced in the still-face episode with infants exhibiting typical “still-face” behaviours and elevated SC responses. The results indicated that in the reunion episode, mother’s singing was more effective in decreasing infant’s physiological arousal, regulating negative affect and promoting infants’ visual attention in comparison to maternal speaking. However, the genre of songs selected (e.g., play song or lullaby) might have been contributed to the positive outcomes of singing in regulating infants’ emotions. Therefore, the second study used the same methodology to examine the effects of maternal play songs and lullabies on infants’ physiological and behavioural responses. The results indicated that maternal play songs were more effective in regulating infants’ stress as well as capturing and maintaining their attention than were soothing lullabies. Taken together, the findings indicate that maternal singing, specifically playful performances, supports infants’ emotions and effectively regulates their stress.