i Socialisation and psychological wellbeing: Modelling the impact of the prenatal maternal social environment on offspring mental health outcomes in middle childhood Eric Spikol BSc. (Honours) Psychology School of Psychology Faculty of Life & Health Sciences Ulster University Thesis submitted for the degree of Doctor of Philosophy September 2020 I confirm that the word count of this thesis is less than 100,000 words excluding the title page, contents, acknowledgements, summary or abstract, abbreviations, footnotes, diagrams, maps, illustrations, tables, appendices, and references or bibliography. ii Contents Page List of tables iii List of figures vi Acknowledgements vii Summary viii Abbreviations xi Chapter 1: Main introduction 1 1.1. Introduction: Thesis Proposal 2 1.2. Evolutionary Influences on Psychology 3 1.3. An Introduction to Epigenetic Theory 6 1.4. Prenatal Stress and the Prenatal Environmental Adaptation 9 Hypothesis 1.5. Epigenetics and Psychopathology 13 1.6. Social Isolation as a Deficit Environment 15 1.7. Thesis Overview 19 1.7.1. Chapter 3: Modelling the prenatal maternal social 19 environment 1.7.2. Chapter 4: Specific profiles within the maternal population 20 1.7.3. Chapter 5: Modelling the childhood social environment 21 1.7.4. Chapter 6: Modelling psychopathology across middle 21 childhood 1.7.5. Chapter 7: Testing the impact of socialisation on 22 psychopathology 1.8. Thesis Aims, Goals, and Justification 22 1.9. Introduction References 25 Chapter 2: ALSPAC in theory and in practice 42 2.1. Introduction 43 2.2. Aims 43 iii 2.3. Overall Design 44 2.4. Sample 46 2.4.1 Study area 46 2.4.2. Eligibility, recruitment, enrolment, and attrition 46 2.4.3. Mortality 49 2.4.4. General cohort demographics 50 2.5. Measures 52 2.5.1 Chapter 3 measures and variables 52 2.5.2 Chapter 4 measures and variables 54 2.5.3 Chapter 5 measures and variables 57 2.5.3.1 Child measures and variables 58 2.5.3.2 Maternal measures and variables 59 2.5.4 Chapter 6 measures and variables 60 2.5.5 Chapter 7 measures and variables 62 2.5.5.1 Thesis-derived variables 63 2.5.5.2 Maternal measures and variables 64 2.5.5.3 Child measures and variables 71 2.6. Data Collection 71 2.6.1. Physical data collection 72 2.6.2. Questionnaires 73 2.6.3. In-home environmental monitoring 76 2.6.4. Health and education records 77 2.7. Data Use Permissions and Ethics 78 2.8. On-Going Research 78 2.9. Language Use 78 2.10. Chapter References 80 Chapter 3: Modelling the prenatal maternal social environment 86 3.1. Study Introduction 87 3.1.1 Prenatal epigenetics in humans 88 3.1.2. Socialisation in humans 91 3.1.3. Study aims 96 3.2. Methodology 97 3.2.1. Sample 97 iv 3.2.2. Measures 97 3.2.3. Analytic strategy 98 3.3. Results 100 3.4. Discussion 109 3.4.1. Model results and selection 109 3.4.2. Dimensions of the prenatal maternal social environment 110 3.4.3. Model discussion 115 3.4.4. Limitations 116 3.4.5. Impact and implications 116 3.4.6. Conclusions 118 3.5. Chapter References 119 Chapter 4: Specific profiles within the maternal population 135 4.1. Study Introduction 136 4.1.1. Latent Profiles in a Population 137 4.1.2. Regression and Covariate Predictors 139 4.1.3. Study Aims 143 4.2. Methods 144 4.2.1. Sample 144 4.2.2. Measures 144 4.2.3. Analytic Strategy 144 4.2.3.1 Step 1: define distinct profiles 144 4.2.3.2. Step 2: identify predictor covariates to profile 146 membership 4.3. Results 146 4.4. Discussion 154 4.4.1. Latent Class Division 154 4.4.2. Covariate Predictors 155 4.4.3. Model discussion 162 4.4.4. Limitations 163 4.4.5. Impact and implications 163 4.4.6. Conclusions 164 4.5. Chapter References 165 v Chapter 5: Modelling the childhood social environment 181 5.1. Study Introduction 182 5.1.1. Socialisation in middle childhood 182 5.1.2. Social isolation in middle childhood 185 5.1.3. Maternal influences on the childhood social environment 188 5.1.4. Childhood covariates and the social environment 190 5.1.5. Study aims 192 5.2. Methodology 193 5.2.1. Sample 193 5.2.2. Measures 193 5.2.2.1. Child-completed data 194 5.2.2.2. Maternal covariates 194 5.2.2.3. Child covariates 194 5.2.3. Analytic strategy 194 5.2.3.1. Step 1: model the child social environment 195 5.2.3.2. Step 2: determine relationships between factors 196 and indicators 5.3. Results 197 5.4. Discussion 207 5.4.1. Model selection and results 207 5.4.2. Covariate Indicators 208 5.4.3. Limitations 212 5.4.4. Impact and implications 213 5.4.5. Conclusions 214 5.5. Chapter References 215 Chapter 6: Modelling psychopathology across middle childhood 238 6.1. Study Introduction 239 6.1.1. Psychopathology in middle childhood 240 6.1.2. Psychopathology trajectories in middle childhood 245 6.1.3. Latent growth and latent growth mixture modelling 248 6.1.4. Study aims 250 6.2. Methodology 251 6.2.1. Sample 251 vi 6.2.2. Measures 251 6.2.3. Analytic Strategy 252 6.3. Results 253 6.4. Discussion 259 6.4.1. Model Results 259 6.4.2. Model discussion 261 6.4.3. Limitations 263 6.4.4. Impact and implications 264 6.4.5. Conclusions 264 6.5. Chapter References 266 Chapter 7: Testing the impact of socialisation on psychopathology 288 7.1. Study Introduction 289 7.1.1. Exploring environmental effects 290 7.1.2. Controlling for the postnatal environment 292 7.1.2.1 The Postnatal Environment: Maternal Influence 293 7.1.2.2. The Postnatal Environment: Child Experiences 298 7.1.2.3. Mother/Child Socialisation Categorisation 299 7.1.3. Study Aims 300 7.2. Methodology 301 7.2.1. Sample 301 7.2.2. Measures 301 7.2.2.1. Thesis derived measures 301 7.2.2.2. Maternal covariates 302 7.2.2.3. Child-based covariates 302 7.2.3. Analytic strategy 302 7.3. Results 303 7.4. Discussion 322 7.4.1. Model Results 322 7.4.2. Model discussion 323 7.4.3. Limitations 327 7.4.4. Impact and implications 328 7.4.5. Conclusions 330 7.5. Chapter References 331 vii Chapter 8: General discussion 346 8.1. Introduction 347 8.2. Thesis Results 349 8.3. Genetic Contributions to Psychopathology 354 8.4. Adolescent Socialisation 358 8.5. Adolescent Psychopathology 361 8.6. Future Directions 365 8.7. The Prenatal Maternal Social Environment and Psychosis 368 8.8. Thesis Limitations 370 8.9. Conclusions 373 8.10. Chapter References 378 Appendix A 408 Appendix B 410 Appendix C 412 Appendix D 414 viii List of Tables Table Page Chapter 2 2.1 Descriptive statistics for main maternal socio-demographic variables 52 2.2 Strengths and difficulties questionnaire items and ALSPAC recoding 62 information 2.3 ALSPAC self-complete questionnaire schedule 74 2.4 ALSPAC child-based questionnaire schedule 76 Chapter 3 3.1 Populations and percentages for social scale item endorsement 100-101 3.2. Fit indices for exploratory factor analysis 102 3.3. Factor loadings for a unidimensional model 103 3.4. Factor loadings and correlation for a 2-factor model 104 3.5. Factor loadings and correlations for a 3-factor model 105 3.6. Factor loadings and correlations for a 4-factor model 106 3.7. Factor loading scores and correlations for a 5-factor model 107 Chapter 4 4.1. Population counts and percentages for maternal variables 147 4.2. Fit indices for latent profile analysis 148 4.3. Covariate predictors of socialisation profile membership 153 Chapter 5 5.1. Population counts and percentages for socialisation scale item 198-199 endorsement 5.2. Population counts and percentages for non-trauma covariates 200 5.3. Population counts and percentages of child life events ages 201 1.5 – 8.5 years 5.4. Fit indices for exploratory measurement models 202 5.5. Information criteria for exploratory measurement models 202 5.6. Factor loadings for a unidimensional model 203 5.7. Covariate indicators in a unidimensional model 203 5.8. Factor loadings and correlations for a 2-factor model 204 5.9. Covariate indicators in a 2-factor model 204 ix 5.10. Factor loadings and correlations for a 3-factor model 205 5.11. Covariate indicators in a 3-factor model 206 Chapter 6 6.1. Descriptive statistics for SDQ scores at ages 7, 9, and 11 years 254 6.2. Fit statistics for the GLM models of the SDQ 255 6.3. Parameter estimates for SDQ scores in a linear model 256 6.4. Fit indices for LGMM with and without slope variance 257 6.5. Parameter estimates for a 4-class model 258 Chapter 7 7.1. Population counts and percentages of maternal prenatal 303 socialisation profiles 7.2. Population counts and percentages of child socialisation tertiles 304 7.3. Population counts and percentages of child psychopathology 304 trajectories 7.4. Population counts and percentages of maternal/child 305 socialisation categories 7.5. Maternal demographics and prenatal covariates descriptive 306 statistics and population counts 7.6. Descriptive statistics for Crown-Crisp Experimental Index 308 sub-scores 7.7. Population counts of clinical instances of anxiety, somatic 309 symptoms, and depression during the postnatal period 7.8.