Breastfeeding, brain activation to own infant cry, and maternal sensitivity

Epidural analgesia during labor: impact on delivery outcome, neonatal well-being, and early breastfeeding

BACKGROUND

The effect of epidural analgesia on labor and effective breastfeeding is still being debated. The aim of this study is to define its impact on the trend of labor, the newborns' well-being, and early breastfeeding.

METHODS

We considered first-term physiologic pregnant women who delivered by the vaginal route. We divided them into two groups: group A received epidural analgesia during labor, whereas group B received no analgesia. We recorded maternal age, gestational age, modality of delivery, length of labor, and length of active labor. All newborns received skin-to-skin contact; early breastfeeding was encouraged. We recorded data on birth weight and length, Apgar score at minutes 1 and 5, type of crying, neonatal reactivity, and time between birth and exposure to the breast. Statistical significance was considered for p<0.05.

RESULTS

Of 934 pregnant women who delivered by the vaginal route, 317 patients required labor analgesia, and 245 patients agreed to participate in our study. Only 128 patients met inclusion criteria. We randomized them in 64 women in group A and 64 women in group B. Data on maternal age, gestational age, type of delivery, neonatal birth weight and length, and Apgar score showed no significant differences. Total length of labor was 363.58±62.20 minutes in Group A versus 292.30±64.75 minutes in group B (p<0.001). The length of active labor showed no significant difference. Among neonatal parameters we found a statistically significant difference only for length of first breastfeeding, with a mean duration of <30 minutes in 62.2% in group A versus 29.3% in Group B (p<0.001).

CONCLUSIONS

Epidural analgesia has little effect on trend of labor and duration of first breastfeed and none on neonatal outcome. A new protocol of epidural analgesia may solve these side effects.

Neuroscience of human social interactions and adult attachment style

Since its first description four decades ago, attachment theory (AT) has become one of the principal developmental psychological frameworks for describing the role of individual differences in the establishment and maintenance of social bonds between people. Yet, still little is known about the neurobiological underpinnings of attachment orientations and their well-established impact on a range of social and affective behaviors. In the present review, we summarize data from recent studies using cognitive and imaging approaches to characterize attachment styles and their effect on emotion and social cognition. We propose a functional neuroanatomical framework to integrate the key brain mechanisms involved in the perception and regulation of social emotional information, and their modulation by individual differences in terms of secure versus insecure (more specifically avoidant, anxious, or resolved versus unresolved) attachment traits. This framework describes how each individual's attachment style (built through interactions between personal relationship history and predispositions) may influence the encoding of approach versus aversion tendencies (safety versus threat) in social encounters, implicating the activation of a network of subcortical (amygdala, hippocampus, striatum) and cortical (insula, cingulate) limbic areas. These basic and automatic affective evaluation mechanisms are in turn modulated by more elaborate and voluntary cognitive control processes, subserving mental state attribution and emotion regulation capacities, implicating a distinct network in medial prefrontal cortex (mPFC), superior temporal sulcus (STS), and temporo-parietal junction (TPJ), among others. Recent neuroimaging data suggest that affective evaluation is decreased in avoidantly but increased in anxiously attached individuals. In turn, although data on cognitive control is still scarce, it points toward a possible enhancement of mental state representations associated with attachment insecurity and particularly anxiety. Emotion regulation strategies such as reappraisal or suppression of social emotions are also differentially modulated by attachment style. This research does not only help better understand the neural underpinnings of human social behavior, but also provides important insights on psychopathological conditions where attachment dysregulation is likely to play an important (causal) role.

Parenting and Beyond: Common Neurocircuits Underlying Parental and Altruistic Caregiving

Interpersonal relationships constitute the foundation on which human society is based. The infant-caregiver bond is the earliest and most influential of these relationships. Driven by evolutionary pressure for survival, parents feel compelled to provide care to their biological offspring. However, compassion for non-kin is also ubiquitous in human societies, motivating individuals to suppress their own self-interests to promote the well-being of non-kin members of the society. We argue that the process of early kinship-selective parental care provides the foundation for non-exclusive altruism via the activation of a general Caregiving System that regulates compassion in any of its forms. We propose a tripartite structure of this system that includes (1) the perception of need in another, (2) a caring motivational or feeling state, and (3) the delivery of a helping response to the individual in need. Findings from human and animal research point to specific neurobiological mechanisms including activation of the insula and the secretion of oxytocin that support the adaptive functioning of this Caregiving System.

Meta-analysis of long-chain polyunsaturated fatty acid supplementation of formula and infant cognition

BACKGROUND AND OBJECTIVE

Infant formula is supplemented with long-chain polyunsaturated fatty acids (LCPUFAs) because they are hypothesized to improve cognition. Several randomized controlled clinical trials have examined the effect of LCPUFA supplementation of infant formula on cognitive development. We conducted this meta-analysis to examine the efficacy of LCPUFA supplementation of infant formula on early cognitive development.

METHODS

Two authors searched PubMed, PsychInfo, and Scopus for randomized controlled clinical trials assessing the efficacy of LCPUFA supplementation of infant formulas on cognition. Our analysis was restricted to randomized controlled clinical trials that examined the effect of LCPUFA supplementation on infant cognition using Bayley Scales of Infant Development. Our primary outcome was the weighted mean difference in Bayley Scales of Infant Development score between infants fed formula supplemented with LCPUFA compared with unsupplemented formula. We conducted secondary subgroup analyses and meta-regression to examine the effects of study sample, LCPUFA dose, and trial methodologic quality on measured efficacy of supplementation.

RESULTS

Twelve trials involving 1802 infants met our inclusion criteria. Our meta-analysis demonstrated no significant effect of LCPUFA supplementation of formula on infant cognition. There was no significant heterogeneity or publication bias between trials. Secondary analysis failed to show any significant effect of LCPUFA dosing or prematurity status on supplementation efficacy.

CONCLUSIONS

LCPUFA supplementation of infant formulas failed to show any significant effect on improving early infant cognition. Further research is needed to determine if LCPUFA supplementation of infant formula has benefits for later cognitive development or other measures of neurodevelopment.

Breastfeeding and its relation to maternal sensitivity and infant attachment

OBJECTIVE

To examine the association of breastfeeding with maternal sensitive responsiveness and infant-mother attachment security and disorganization.

METHODS

We included 675 participants of a prospective cohort study. Questionnaires about breastfeeding practices were administered at 2 and 6 months postpartum. At 14 months, maternal sensitive responsiveness was assessed in a 13-minute laboratory procedure using Ainsworth's sensitivity scales, and attachment quality was assessed with the Strange Situation Procedure. Mothers were genotyped for oxytocin receptor genes OXTR rs53576 and OXTR rs2254298. Linear regressions and analyses of covariance adjusted for various background variables were conducted. We tested for mediation and moderation by maternal sensitive responsiveness and maternal oxytocin receptor genotype.

RESULTS

Continuous analyses showed that longer duration of breastfeeding was associated with more maternal sensitive responsiveness (B = 0.11, 95% confidence interval [CI] 0.02; 0.20, p < .05), more attachment security (B = 0.24, 95% CI = 0.02; 0.46, p < .05), and less attachment disorganization (B = -0.20, 95% CI -0.36; -0.03, p < .05). Duration of breastfeeding was not related to the risk of insecure-avoidant or insecure-resistant versus secure attachment classification, but longer duration of breastfeeding predicted a lower risk of disorganized versus secure attachment classification (n = 151; odds ratio [OR] = 0.81, 95% CI 0.66 to 0.99, p = .04). Maternal sensitive responsiveness did not mediate the associations, and maternal oxytocin receptor genotype was not a significant moderator.

CONCLUSIONS

Although duration of breastfeeding was not associated with differences in infant-mother attachment classifications, we found subtle positive associations between duration of breastfeeding and sensitive responsiveness, attachment security, and disorganization.

The neural correlates of maternal sensitivity: an fMRI study

Research on maternal neural response to infant distress highlights circuits that may underlie differences in quality of maternal behavior. However, it is far from clear which circuits are relevant to maternal sensitivity, as opposed to other maternal behavioral dimensions, particularly after the early postpartum. This study examined maternal sensitivity, intrusiveness, and mother-infant dyadic harmony as correlates of mothers' neural responses to the cries of their own infants. Twenty-two primiparous mothers were observed during an interaction with their infants at 18 months postpartum. In a separate functional neuroimaging session, mothers were exposed to their own infant's cry sound, as well as unfamiliar infant's cry and control sounds. Mothers who displayed more sensitive behaviors with their infant exhibited greater activation to their own infant's cry compared to that of an unfamiliar infant in the right frontal pole and inferior frontal gyrus. Mothers who displayed more intrusive behaviors with their infant showed greater activation in the left anterior insula and temporal pole, while mothers who had more harmonious interactions with their infant displayed greater activation in left hippocampal regions. The roles of these areas in the regulation of maternal emotion and stress, self and other awareness, and empathy are examined.

Oxytocin and social affiliation in humans

A conceptual model detailing the process of bio-behavioral synchrony between the online physiological and behavioral responses of attachment partners during social contact is presented as a theoretical and empirical framework for the study of affiliative bonds. Guided by an ethological behavior-based approach, we suggest that micro-level social behaviors in the gaze, vocal, affective, and touch modalities are dynamically integrated with online physiological processes and hormonal response to create dyad-specific affiliations. Studies across multiple attachments throughout life are presented and demonstrate that the extended oxytocin (OT) system provides the neurohormonal substrate for parental, romantic, and filial attachment in humans; that the three prototypes of affiliation are expressed in similar constellations of social behavior; and that OT is stable over time within individuals, is mutually-influencing among partners, and that mechanisms of cross-generation and inter-couple transmission relate to coordinated social behavior. Research showing links between peripheral and genetic markers of OT with concurrent parenting and memories of parental care; between administration of OT to parent and infant's physiological readiness for social engagement; and between neuropeptides and the online synchrony of maternal and paternal brain response in social-cognitive and empathy networks support the hypothesis that human attachment develops within the matrix of biological attunement and close behavioral synchrony. The findings have conceptual implications for the study of inter-subjectivity as well as translational implications for the treatment of social disorders originating in early childhood, such as autism spectrum disorders, or those associated with disruptions to early bonding, such as postpartum depression or child abuse and neglect. This article is part of a Special Issue entitled Oxytocin, Vasopressin, and Social Behavior.

Neuroendocrinology of parental response to baby-cry

This overview attempts to synthesise current understandings of the neuroendocrine basis of parenting. The parent-infant bond is central to the human condition, contributes to risks for mood and anxiety disorders, and provides the potential for resiliency and protection against the development of psychopathology. Animal models of parenting provide compelling evidence that biological mechanisms may be studied in humans. This has led to brain imaging and endocrine system studies of human parents using baby stimuli and concerted psychological and behavioural measures. Certain brain circuits and related hormonal systems, including subcortical regions for motivation (striatum, amygdala, hypothalamus and hippocampus) and cortical regions for social cognition (anterior cingulate, insula, medial frontal and orbitofrontal cortices), appear to be involved. These brain circuits work with a range of endocrine systems to manage stress and motivate appropriate parental caring behaviour with a flexibility appropriate to the environment. Work in this field promises to link evolving models of parental brain performance with resilience, risk and treatment toward mother-infant mental health.

Maternal neglect: oxytocin, dopamine and the neurobiology of attachment

Maternal neglect, including physical and emotional neglect, is a pervasive public health challenge with serious long-term effects on child health and development. I provide an overview of the neurobiological basis of maternal caregiving, aiming to better understand how to prevent and respond to maternal neglect. Drawing from both animal and human studies, key biological systems are identified that contribute to maternal caregiving behaviour, focusing on the oxytocinergic and dopaminergic systems. Mesocorticolimbic and nigrostriatal dopamine pathways contribute to the processing of infant-related sensory cues leading to a behavioural response. Oxytocin may activate the dopaminergic reward pathways in response to social cues. Human neuroimaging studies are summarised that demonstrate parallels between animal and human maternal caregiving responses in the brain. By comparing different patterns of human adult attachment, we gain a clearer understanding of how differences in maternal brain and endocrine responses may contribute to maternal neglect. For example, in insecure/dismissing attachment, which may be associated with emotional neglect, we see reduced activation of the mesocorticolimbic dopamine reward system in response to infant face cues, as well as decreased peripheral oxytocin response to mother-infant contact. We are currently testing whether the administration of intranasal oxytocin, as part of a randomised placebo controlled trial, may reverse some of these neurological differences, and potentially augment psychosocial and behavioural interventions for maternal neglect.

The crying baby: what approach?

PURPOSE OF REVIEW

Cry-fuss problems are among the most common clinical presentations in the first few months of life and are associated with adverse outcomes for some mothers and babies. Cry-fuss behaviour emerges out of a complex interplay of cultural, psychosocial, environmental and biologic factors, with organic disturbance implicated in only 5% of cases. A simplistic approach can have unintended consequences. This article reviews recent evidence in order to update clinical management.

RECENT FINDINGS

New research is considered in the domains of organic disturbance, feed management, maternal health, sleep management, and sensorimotor integration. This transdisciplinary approach takes into account the variable neurodevelopmental needs of healthy infants, the effects of feeding management on the highly plastic neonatal brain, and the bi-directional brain-gut-enteric microbiota axis. An individually tailored, mother-centred and family-centred approach is recommended.

SUMMARY

The family of the crying baby requires early intervention to assess for and manage potentially treatable problems. Cross-disciplinary collaboration is often necessary if outcomes are to be optimized.

Oxytocin and social motivation

Humans are fundamentally social creatures who are ‘motivated’ to be with others. In this review we examine the role of oxytocin (OT) as it relates to social motivation. OT is synthesized in the brain and throughout the body, including in the heart, thymus, gastrointestinal tract, as well as reproductive organs. The distribution of the OT receptor (OTR) system in both the brain and periphery is even more far-reaching and its expression is subject to changes over the course of development. OTR expression is also sensitive to changes in the external environment and the internal somatic world. The OT system functions as an important element within a complex, developmentally sensitive biobehavioral system. Other elements include sensory inputs, the salience, reward, and threat detection pathways, the hypothalamic-pituitary-gonadal axis, and the hypothalamic-pituitary-adrenal stress response axis. Despite an ever expanding scientific literature, key unresolved questions remain concerning the interplay of the central and peripheral components of this complex biobehavioral system that dynamically engages the brain and the body as humans interact with social partners over the course of development.

Becoming a parent: biobehavioral and brain science perspectives

This overview is a synthesis of our current understanding of parent-infant bonding, chiefly from the perspective of the parent's brain physiology. The parent-infant bond is central to the human condition, contributes to risks for mood and anxiety disorders, and provides potential resiliency and protection against the development of psychopathology throughout life. While the complex nature of the phenomena and experimental approaches leads to the consideration of many overlapping parenting brain systems, including sensory, emotion, and cognition to support behavior, a relatively small set of brain regions seem to be robustly involved. These include basal ganglia and related cortex for emotion and drive (striatum, amygdala, hypothalamus, and hippocampus), and regulatory cortical regions (anterior cingulate, insula medial frontal, and orbitofrontal cortices). Work in this field promises to link parental brain performance with resilience, risk, and appropriate treatment toward infant mental health.

The human parental brain: in vivo neuroimaging

Interacting parenting thoughts and behaviors, supported by key brain circuits, critically shape human infants' current and future behavior. Indeed, the parent-infant relationship provides infants with their first social environment, forming templates for what they can expect from others, how to interact with them and ultimately how they go on to themselves to be parents. This review concentrates on magnetic resonance imaging experiments of the human parent brain, which link brain physiology with parental thoughts and behaviors. After reviewing brain imaging techniques, certain social cognitive and affective concepts are reviewed, including empathy and trust-likely critical to parenting. Following that is a thorough study-by-study review of the state-of-the-art with respect to human neuroimaging studies of the parental brain-from parent brain responses to salient infant stimuli, including emotionally charged baby cries and brief visual stimuli to the latest structural brain studies. Taken together, this research suggests that networks of highly conserved hypothalamic-midbrain-limbic-paralimbic-cortical circuits act in concert to support parental brain responses to infants, including circuits for limbic emotion response and regulation. Thus, a model is presented in which infant stimuli activate sensory analysis brain regions, affect corticolimbic limbic circuits that regulate emotional response, motivation and reward related to their infant, ultimately organizing parenting impulses, thoughts and emotions into coordinated behaviors as a map for future studies. Finally, future directions towards integrated understanding of the brain basis of human parenting are outlined with profound implications for understanding and contributing to long term parent and infant mental health.