Listening to a baby crying induces higher electroencephalographic synchronization among prefrontal, temporal and parietal cortices in adoptive mothers

Electroencephalographic activity during direct breastfeeding and breast milk expression in primiparous mothers

Breastfeeding is recognized worldwide as the best option for infant feeding. Expressing breast milk is an alternative for mothers to provide their infants all the benefits of maternal milk. During breast milk expression, mothers receive a distinct kind of sensory stimulation, because there is no direct bodily or affective interaction with their infants, many women report feeling isolated, generating a love-hate relation with pumping, and even low levels of satisfaction while expressing breast milk. While it is well known that the prefrontal, parietal, and temporal cortices play important roles in the emotional and cognitive processing of maternal stimuli, knowledge about how these cortical areas function during breastfeeding is lacking. This study was designed to characterize EEG activity in the prefrontal and parietal cortices and the affective scores of primiparous breastfeeding mothers during two conditions of milk expression: breast milk expression and direct breastfeeding. Participants reported higher valence and arousal and a pleasant state during direct breastfeeding. In the direct breastfeeding condition, both prefrontal areas showed a higher absolute power (AP) of the slow bands, with a lower AP of the alpha band in the parietal cortex. A lower correlation between frontopolar and dorsolateral areas with a higher correlation between prefrontal and parietal cortices was obtained mainly in the right hemisphere. This EEG activity could be linked to an internal state of focused attention and, simultaneously, open monitoring of the environment that suggests an integration of the motive-emotional and cognitive processes necessary for adequate mother-baby interaction during direct breastfeeding.

Motherhood and theory of mind: increased activation in the posterior cingulate cortex and insulae

Despite growing evidence on effects of parenthood on social understanding, little is known about the influence of parenthood on theory of mind (ToM), the capacity to infer mental and affective states of others. It is also unclear whether any possible effects of parenthood on ToM would generalise to inferring states of adults or are specific to children. We investigated neural activation in mothers and women without children while they predicted action intentions from child and adult faces. Region-of-interest analyses showed stronger activation in mothers in the bilateral posterior cingulate cortex, precuneus (ToM-related areas) and insulae (emotion-related areas). Whole-brain analyses revealed that mothers compared to non-mothers more strongly activated areas including the left angular gyrus and the ventral prefrontal cortex but less strongly activated the right supramarginal gyrus and the dorsal prefrontal cortex. These differences were not specific to child stimuli but occurred in response to both adult and child stimuli and might indicate that mothers and non-mothers employ different strategies to infer action intentions from affective faces. Whether these general differences in affective ToM between mothers and non-mothers are due to biological or experience-related changes should be subject of further investigation.

Parenting in the Context of the Child: Genetic and Social Processes

The focus on the role of parenting in child development has a long-standing history. When measures of parenting precede changes in child development, researchers typically infer a causal role of parenting practices and attitudes on child development. However, this research is usually conducted with parents raising their own biological offspring. Such research designs cannot account for the effects of genes that are common to parents and children, nor for genetically influenced traits in children that influence how they are parented and how parenting affects them. The aim of this monograph is to provide a clearer view of parenting by synthesizing findings from the Early Growth and Development Study (EGDS). EGDS is a longitudinal study of adopted children, their birth parents, and their rearing parents studied across infancy and childhood. Families (N = 561) were recruited in the United States through adoption agencies between 2000 and 2010. Data collection began when adoptees were 9 months old (males = 57.2%; White 54.5%, Black 13.2%, Hispanic/Latinx 13.4%, Multiracial 17.8%, other 1.1%). The median child age at adoption placement was 2 days (M = 5.58, SD = 11.32). Adoptive parents were predominantly in their 30s, White, and coming from upper-middle- or upper-class backgrounds with high educational attainment (a mode at 4-year college or graduate degree). Most adoptive parents were heterosexual couples, and were married at the beginning of the project. The birth parent sample was more racially and ethnically diverse, but the majority (70%) were White. At the beginning of the study, most birth mothers and fathers were in their 20s, with a mode of educational attainment at high school degree, and few of them were married. We have been following these family members over time, assessing their genetic influences, prenatal environment, rearing environment, and child development. Controlling for effects of genes common to parents and children, we confirmed some previously reported associations between parenting, parent psychopathology, and marital adjustment in relation to child problematic and prosocial behavior. We also observed effects of children's heritable characteristics, characteristics thought to be transmitted from parent to child by genetic means, on their parents and how those effects contributed to subsequent child development. For example, we found that genetically influenced child impulsivity and social withdrawal both elicited harsh parenting, whereas a genetically influenced sunny disposition elicited parental warmth. We found numerous instances of children's genetically influenced characteristics that enhanced positive parental influences on child development or that protected them from harsh parenting. Integrating our findings, we propose a new, genetically informed process model of parenting. We posit that parents implicitly or explicitly detect genetically influenced liabilities and assets in their children. We also suggest future research into factors such as marital adjustment, that favor parents responding with appropriate protection or enhancement. Our findings illustrate a productive use of genetic information in prevention research: helping parents respond effectively to a profile of child strengths and challenges rather than using genetic information simply to identify some children unresponsive to current preventive interventions.

Multiparity decreases the effect of distractor stimuli on a working memory task: An EEG study

Parity modulates the way in which women respond to infant's affective cues. It is known that the cognitive processing of mothers is affected by a baby crying; however, little information is available regarding the effect of reproductive and caregiving experience on efficiency in managing babies' emotional stimuli while other tasks are being attended. This study characterized the affective score, cognitive performance, and electroencephalographic correlation (rEEG) between prefrontal and parietal cortices in first- (FM) and second-time mothers (SM) while solving a working memory task (vsWM) and simultaneously listening to either an emotional or neutral distractor stimulus. During the vsWM-baby crying condition, both groups reported higher arousal. However, SM reported a lower valence and FM lower dominance. In the vsWM-baby crying condition did SM need less time to solve the cognitive task and present a decreased rEEG between prefrontal areas, and between left prefrontal and parietal areas, though an increased rEEG between parietal areas was observed while listening to both distractor stimuli during performance of the vsWM task. These degrees of cortical synchronization could constitute a cerebral mechanism required to achieve better information maintenance and enhance suppression of distractor effects, which allow the SM women to solve the vsWM task more efficiently.

Observing baby or sexual videos changes the functional synchronization between the prefrontal and parietal cortices in mothers in different postpartum periods

During the postpartum period (PP), mothers are more sensitive to sensory stimuli related to babies and less sensitive to those with sexual significance. The processing of emotional stimuli requires synchronization among different cerebral areas. This study characterized the cortical electroencephalographic (EEG) correlation in mothers from 1½ to 3 months (PP1), 4 to 5½ months (PP2) and over 6½ months, postpartum (PP3) while observing two videos: one of a baby (BV) and one with sexual content (SV). EEGs were recorded from the frontopolar, dorsolateral and parietal cortices. All three groups rated the BV as pleasant, but only PP3 reported higher sexual arousal with the SV. While watching the BV, PP1 showed a higher correlation among all cortical areas; PP2 manifested a decreased correlation between the prefrontal and parietal cortices, likely associated with the lower emotional modulation of the BV; and PP3 presented a higher synchronization among fewer cortical areas, probably related to longer maternal experience. These cortical synchronization patterns could represent adaptive mechanisms that enable the adequate processing of baby stimuli in new mothers. These data increase our knowledge of the cerebral processes associated with distinct sensitivities to the emotional stimuli that mothers experience during the PP.

Prefrontal-posterior coupling mediates transitions between emotional states and influences executive functioning

Emotions often result from fluctuating experiences with self-regulation unfolding over time. However, most research has been focused on neural responses to static, affective stimuli. We studied emotion transitions, which correspond to dynamic conditions of varying affective valence or intensities. Functional coupling of prefrontal and posterior cortex (EEG coherence) was recorded during exposure to stable versus changing emotion-eliciting images (static vs. dynamic conditions). Prefrontal-posterior coupling was decreased in the dynamic conditions compared to the static conditions. A decrease in prefrontal-posterior coupling implies less control of the prefrontal cortex over perceptual information, which may allow the brain to become more affected by emotional fluctuations. We also assessed the aftereffect of EEG coherence on executive functioning, utilizing the flanker task. Among individuals reporting higher chronic stress, executive functioning decreased after dynamic conditions. This decrease in executive functioning was mediated by the decrease in prefrontal-posterior coupling in the dynamic conditions. These findings suggest that the strength of prefrontal-posterior coupling is not only related to emotional transitions but also to executive functioning. The deterioration of executive functioning after dynamic emotional processing may reflect the additional cognitive effort required to process dynamic shifts in affective stimuli, and this relationship is exacerbated by chronic stress.

Why do babies cry?

Persistent, inconsolable crying in young infants is common, distressing but usually benign. This selective review examines perceptions and perceived origins of this phenomenon in babies where serious pathology has been excluded. Adult brains have evolved to become hypersensitive to infant cries. Babies respond to parental stress by crying more, thus setting up a vicious cycle. Most treatments appear to work largely through a placebo effect. The imperative for healthcare professionals is to reduce parental anxiety by offering reassurance and support.