BEHAVIOURAL AND NEUROBIOLOGICAL CORRELATES OF MATERNAL SENSITIVITY IN HEALTHY NEW MOTHERS A thesis submitted to The University of Manchester for the degree of Doctor of Philosophy (PhD) in the Faculty of Medical and Human Sciences 2013 ALYA MOHAMED AHMED ELMADIH SCHOOL OF MEDICINE 1 Table of Contents LIST OF TABLES ..................................................................................................................... 7 LIST OF FIGURES ................................................................................................................... 9 LIST OF DEFINITIONS ......................................................................................................... 10 LIST OF ABBREVIATIONS .................................................................................................. 11 ABSTRACT ............................................................................................................................. 12 DECLARATION ..................................................................................................................... 13 COPYRIGHT STATEMENT .................................................................................................. 13 DEDICATION ......................................................................................................................... 15 ACKNOWLEDGEMENT ....................................................................................................... 16 THE AUTHOR ........................................................................................................................ 17 Chapter 1: General introduction .......................................................................................... 18 1.1 Background .................................................................................................................... 18 1.1.1. Study I (Chapter 2-5 & Publication 1) .................................................................... 19 1.1.2. Study II (Chapter 6-10 & Publication 2 & 3) ......................................................... 23 1.2. Rationale for Submitting the Thesis in an Alternative Format ..................................... 28 1.3. Publications ................................................................................................................... 30 Study I: Natural variation in maternal sensitivity: What are the possible prenatal and postnatal predictors in healthy early postpartum mothers? Chapter 2: Study I Literature Review ................................................................................. 34 2.1. The Prenatal Development of Maternal Sensitivity ...................................................... 34 2.2. What Is Maternal Sensitivity? ....................................................................................... 35 2.3. Why Is Maternal Sensitivity Important? ....................................................................... 37 2.3.1. Child outcomes ....................................................................................................... 37 2.3.2. Parenting quality ..................................................................................................... 41 2.4. How Is Maternal Sensitivity Measured? ....................................................................... 42 2.4.1. Validity of the short single interaction observation ................................................ 42 2.5. Is Maternal Sensitivity a Stable Construct?................................................................... 46 2.6. Factors That Influence Maternal Sensitivity ................................................................. 47 2.6.1. Mother prenatal psychological characteristics ................................................... 51 2.6.2. Socio-demographic and support factors ............................................................. 55 2 2.6.3. Early experiences in family-of-origin ................................................................. 58 2.6.4. Obstetric characteristics ..................................................................................... 61 2.6.5. Infant temperamental behaviours....................................................................... 63 2.7. Summary ....................................................................................................................... 64 2.8. Study I Objectives ......................................................................................................... 66 Chapter 3: Study 1 Methodology .......................................................................................... 67 3.1. Sample ........................................................................................................................... 67 3.2. Measures ........................................................................................................................ 70 3.2.1. The Edinburgh Postnatal Depression Scale (EPDS) (Cox et al., 1987) ................. 70 3.2.2. The Hospital Anxiety and Depression (HADS) rating scale (Zigmond & Snaith, 1983) ..................................................................................................................... 70 3.2.3. Maternal-Fetal Attachment Scale (MFAS) (Cranley, 1981) .................................. 70 3.2.4. Parental Bonding Instrument (PBI) (Parker et al., 1979) ....................................... 71 3.2.5. Childhood Trauma Questionnaire (CTQ) (Bernstein et al., 1997) ......................... 71 3.2.6. The Oslo 3-items social support scale (Dalgard, 1996) .......................................... 72 3.2.7. The Manchester Assessment of Caregiver-Infant Interaction (MACI) (Wan et al., 2012, 2013 online) ...................................................................................................... 72 3.2.8. Infant Behaviour Questionnaire Revised Very Short Form (IBQ-R-v. short) (Gartstein & Rothbart, 2003) ............................................................................................ 75 3.3. Procedure ....................................................................................................................... 75 3.3.1. Time 1 (Pregnancy) ................................................................................................ 75 3.3.2. Time 2 (4-6 months postpartum) ............................................................................ 76 3.4. Statistical Analyses ........................................................................................................ 78 3.4.1. Sample size ............................................................................................................. 78 3.4.2. Data analyses .......................................................................................................... 78 3.5. Ethical Considerations ................................................................................................... 79 3.5.1. Ethics ...................................................................................................................... 79 3.5.2. Benefits to research participants ............................................................................. 79 3.5.3. Safety considerations .............................................................................................. 80 Chapter 4: Study I Results .................................................................................................... 81 4.1. Sample Characteristics .................................................................................................. 81 4.2. Characteristics of Mother-Infant Interaction (Manchester Assessment of Caregiver-Infant Interaction; MACI rating) ......................................................................... 83 4.3. Preliminary Analyses (association of prenatal/postnatal factors with maternal sensitivity) ............................................................................................................................ 83 3 4.3.1. Prenatal variables .................................................................................................... 83 4.3.2. Postnatal variables .................................................................................................. 87 4.4. Main analyses: Predictors of maternal sensitivity (Stepwise regression) ..................... 87 Chapter 5: Study I Discussion ............................................................................................... 90 5.1. Overview of the Findings .............................................................................................. 90 5.2. Mother-Infant Interaction .............................................................................................. 91 5.3. Predictors of Maternal Sensitivity ................................................................................. 91 5.4. Associations between Maternal Sensitivity and Prenatal/Postnatal Variables .............. 94 5.4.1. Prenatal variables .................................................................................................... 94 5.4.2. Postnatal variables .................................................................................................. 97 Publication 1 ........................................................................................................................... 99 Study II: Neurobiological mechanisms underlying maternal behaviour in humans: Do the brain and endocrine responses to infant stimuli in less sensitive mothers differ from those in sensitive