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This thesis uses an exploratory sequential design to examine the relationship between maternal anxiety and infant feeding from pregnancy to parenthood. Chapter 1 provides an overview of the thesis and a contextual framework of breastfeeding behaviour. Chapter 2 systematically reviews the literature examining prenatal anxiety and infant feeding, while Chapter 3 systematically reviews the literature examining postpartum anxiety and infant feeding. Chapter 4 uses qualitative, longitudinal methods to explore the impact of pregnancy-specific anxiety on prenatal infant feeding intentions and subsequent postpartum breastfeeding behaviour. Chapters 5 and 6 examine the emotional and practical experiences of breastfeeding and formula feeding women to identify potentially influencing mechanisms within the relationship. Chapter 7 reports the development and validation of a new measure of postpartum-specific anxiety. Chapter 8 then examines whether this measure is a more effective predictor of infant feeding outcomes than a general measure of anxiety. First, the findings reveal that there is insufficient evidence to make firm conclusions regarding the relationship between prenatal anxiety and infant feeding outcomes. However, the thesis finds convincing evidence for the relationship between postpartum anxiety and diverse infant feeding outcomes and behaviours. Second, a qualitative, longitudinal design suggests that pregnancy-specific anxiety may strengthen breastfeeding intentions in pregnancy, but this does not translate into improved breastfeeding outcomes postpartum. Third, the findings provide consistent evidence that failure to adhere to current infant feeding recommendations elicits negative emotional and practical experiences, which may potentially influence the relationship. Finally, the findings reveal new evidence for the efficacy of a validated measure of postpartum specific anxiety, relative to general measures of anxiety and depression, in predicting infant feeding outcomes and behaviours. Collectively, this thesis demonstrates that maternal anxiety, particularly in the months following childbirth is; like depression; an individual-level determinant of breastfeeding. Policy makers should raise awareness of this under-recognised psychological determinant, and distinguish it from depression, and anxiety occurring at other times of life.

Hunger and pain are powerful homeostatic drives, which compete for a behavioural response when experienced simultaneously. This thesis set out to explore neural mechanisms underpinning this competition, and how appetitive visual and olfactory stimuli may modulate the effect of homeostatic energy manipulations on pain. Using well-established techniques including EEG source analysis and resting state fMRI, we consistently employed a within-subjects fasting vs. satiation paradigm to investigate the effects of appetite on subjective pain perception and neural pain processing. Pain stimuli which selectively activated nociceptive Aδ fibres were presented concurrently with appetitive stimuli, and the neural nociceptive responses were mapped with high-density (128-channel) EEG recordings and fMRI functional connectivity. Based on the results of previous research, we hypothesised that fasting would suppress subjective and neural pain processing, and that visual and olfactory appetitive stimuli may augment this effect. We first found that a relatively short overnight fast was sufficient to induce significant changes in resting state functional connectivity in areas that underlie both hunger/satiety and pain: insula cortex, hypothalamus, and regions of prefrontal cortex. Source analysis of EEG data revealed a small group of brain regions whose pain-related activation was suppressed by hunger and/or appetitive stimuli: anterior cingulate cortex, operculo-insular cortex, parahippocampal cortex, and cerebellum. Functional connectivity analysis of fMRI data further uncovered a widely-distributed network of brain areas whose pain-induced connectivity was enhanced by fasting or satiety. Of particular interest was a small network of areas involved in stimulus saliency processing (anterior insula, anterior cingulate cortex, and prefrontal cortex), which was stronger during fasting; presumably advantageous when searching for food. Lastly, in an experiment using a bread odour, we found that the suppressive effect of appetitive stimuli on nociception is not just confined to the visual modality. Brief, strong pain can also be suppressed by an appetitive odour during fasting. We conclude that fasting reliably interferes with pain processing, and that ambient appetitive stimuli might be of use in situations where short-lasting pain is likely to occur.

Background: Experimental studies have shown that exposure to food advertising on television can affect children’s food preferences, choices and consumption in the short-term. However, little is known about the role of habitual television viewing (and therefore food advert exposure) and its potential relationship with brand awareness, brand requests, food preferences and weight status in children. The published research examining the UK television food advertising landscape also has a number of limitations that restrict its usefulness in assessing the potential influence of such food promotion on children’s diets. The current thesis used innovative methodologies to examine hypotheses arising from these issues in 6-13 year old children and on the UK television channels most popular with this age group. Key Findings: Effects of acute, experimental food advertising exposure (Chapter 3): Relative to toy advertisement exposure, food advertising exposure increased all children’s selection of branded and non-branded fat and carbohydrate items from food preference measures. No weight status differences in food preferences or response to advertising were found. Preferences for branded food items were particularly enhanced in high TV viewing children following food adverts suggesting that these children may have an increased susceptibility to these messages. However, all children were better able to recognise food adverts than toy adverts. Effects of habitual food advertising exposure (Chapters 3-5): Food preference differences between high and low TV viewers were evident in the absence of experimental television food advertising exposure in Chapters 4 and 5. All children were better able to correctly identify product names from brand character stimuli than vice versa. Higher habitual advertising exposure did not confer a greater ability to recognise food advertisements (Chapter 3) nor identify brand characters or products. Children with greater brand awareness did not display greater self-reported preferences for branded food items. The extent of food advertising on UK television (Chapter 6): Food advertising on television varied across channels, channel types, broadcast platforms, viewing times and recording periods (months of the year). The foods advertised on the channels most popular with young people were predominantly unhealthy items, even during periods when large numbers of children are watching, with promotions for healthy foods comprising less than a fifth of all food advertisements. The nature of food advertising on UK television (Chapter 6): Promotional characters (such as brand equity characters, licensed characters and celebrities) were often used to promote unhealthy foods to young people, although their use to promote healthier food items was greatest on dedicated children’s channels. Food adverts aimed at children principally rely on ‘fun’ as a key attribute of both the advertising experience and the use/consumption of the product. Food brand websites were most likely to be promoted during food adverts aimed at teenagers or adults. Implications: This thesis increases understanding of the effects of habitual food advertising exposure on food preferences and food preference responses to acute, experimental food advertising, in addition to providing a comprehensive assessment of the television food advertising landscape in the UK following regulatory reform.