Thinking and doing: the effects of dopamine and oxytocin genes and executive function on mothering behaviours

Maternal Emotional and Behavioral Regulation/Dysregulation and Parenting Practices: A Systematic Review

Emotional and behavioral regulations are crucial for the development of perceptive, responsive, and flexible parenting. Moreover, maternal emotional dysregulation constitutes a risk for maltreatment behaviors. The present study aimed to conduct a systematic review of empirical studies on the associations between mothers' emotional and behavioral regulations and parenting practices with their children or adolescents. A systematic review was conducted, including papers that addressed these variables, analyzing the direct effects, and moderation or mediation effects of maternal emotional and behavioral regulation on parenting practices, targeting child and adolescent samples. We identified 35 studies for analysis. Most of the studies (86%) showed significant associations between maternal emotional and behavioral regulation and parenting practices. Mothers' emotional dysregulation was related to a high risk of maltreatment and negative parenting, such as unsupportive reactions and harsh discipline. High maternal emotional dysregulation and negative parenting, in turn, were associated with children's aggressive behaviors. Conversely, when mothers exhibited high emotional regulation, they engaged in more positive and supportive parenting. Additionally, maternal behavioral regulation with inhibitory control and effortful control led to supportive and warm parenting. Individual and contextual factors, such as maternal victimization history and symptoms of inattention and hyperactivity, had effects on maternal emotional dysregulation, which, in turn, impacted their parenting practices. Consequently, emotional and behavioral regulation played a crucial role in mothers' parenting practices with their children and adolescents. The findings of the current review could contribute to planning parenting interventions, including maternal emotional and behavioral regulation skills, aimed at preventing maltreatment of their children.

Impact of virtual adjunctive cognitive remediation therapy on cognitive flexibility and treatment outcomes in comorbid anorexia nervosa and exercise dependence as quantified using novel biomarkers: A stage 1 registered report

OBJECTIVE

Anorexia nervosa (AN) is associated with significant individual mental and physical suffering and public health burden and fewer than half of patients recover fully with current treatments. Comorbid exercise dependence (ExD) is common in AN and associated with significantly worse symptom severity and treatment outcomes. Research points to cognitive inflexibility as a prominent executive function inefficiency and transdiagnostic etiologic and maintaining mechanism linking AN and ExD. This study will evaluate the initial efficacy of adjunctive Cognitive Remediation Therapy (CRT), which has been shown to produce cognitive improvements in adults with AN, in targeting cognitive inflexibility in individuals with comorbid AN and ExD. As an exploratory aim, this study also addresses the current lack of quick and cost-effective assessments of cognitive flexibility by establishing the utility of two proposed biomarkers, heart rate variability and salivary oxytocin.

METHOD

We will conduct a single-group, within-subjects trial of an established CRT protocol delivered remotely as an adjunct to inpatient or intensive outpatient treatment as usual (TAU) to adult patients (n = 42) with comorbid AN and ExD. Assessments, including self-report, neuropsychological, and biomarker measurements, will occur at three time points.

RESULTS

We expect CRT to increase cognitive flexibility transdiagnostically and consequently, along with TAU, positively impact AN and ExD compulsivity and symptom severity, including weight gain.

DISCUSSION

Findings will inform the development of more effective integrative interventions for AN and ExD targeting shared mechanisms and facilitate the routine assessment of cognitive flexibility as a transdiagnostic risk and maintaining factor across psychopathologies in clinical and research settings.

PUBLIC SIGNIFICANCE

Patients with anorexia nervosa often engage in excessive exercise, leading to harmful outcomes, including increased suicidal behavior. This study examines the preliminary efficacy of an intervention that fosters flexible and holistic thinking in patients with problematic eating and exercise to, along with routine treatment, decrease harmful exercise symptoms. This study also examines new biological markers of the inflexible thinking style thought to be characteristic of anorexia nervosa and exercise dependence.

Roles of the Oxytocin Receptor (OXTR) in Human Diseases

The oxytocin receptor (OXTR), encoded by the OXTR gene, is responsible for the signal transduction after binding its ligand, oxytocin. Although this signaling is primarily involved in controlling maternal behavior, it was demonstrated that OXTR also plays a role in the development of the nervous system. Therefore, it is not a surprise that both the ligand and the receptor are involved in the modulation of behaviors, especially those related to sexual, social, and stress-induced activities. As in the case of every regulatory system, any disturbances in the structures or functions of oxytocin and OXTR may lead to the development or modulation of various diseases related to the regulated functions, which in this case include either mental problems (autism, depression, schizophrenia, obsessive-compulsive disorders) or those related to the functioning of reproductive organs (endometriosis, uterine adenomyosis, premature birth). Nevertheless, OXTR abnormalities are also connected to other diseases, including cancer, cardiac disorders, osteoporosis, and obesity. Recent reports indicated that the changes in the levels of OXTR and the formation of its aggregates may influence the course of some inherited metabolic diseases, such as mucopolysaccharidoses. In this review, the involvement of OXTR dysfunctions and OXTR polymorphisms in the development of different diseases is summarized and discussed. The analysis of published results led us to suggest that changes in OXTR expression and OXTR abundance and activity are not specific to individual diseases, but rather they influence processes (mostly related to behavioral changes) that might modulate the course of various disorders. Moreover, a possible explanation of the discrepancies in the published results of effects of the OXTR gene polymorphisms and methylation on different diseases is proposed.

The role of interindividual licking received and dopamine genotype on later-life licking provisioning in female rat offspring

INTRODUCTION

Rat mothers exhibit natural variations in care that propagate between generations of female offspring. However, there is limited information on genetic variation that could influence this propagation.

METHODS

We assessed early-life maternal care received by individual female rat offspring, later-life maternal care provisioning, and dopaminergic activity in the maternal brain in relation to naturally occurring genetic polymorphisms linked to the dopaminergic system. We also conducted a systematic analysis of other genetic variants potentially related to maternal behavior in our Long-Evans rat population.

RESULTS

While we did not find a direct relationship between early-life licking received and later-life licking provisioning, this relationship was indirectly affected by dopamine levels in the nucleus accumbens and dependent on variation in the dopamine receptor 2 gene (rs107017253). More specifically, female rat offspring with the A/G genotype showed a positive relationship between average licking received and dopamine levels in the nucleus accumbens of the maternal brain; there was no relationship with female rat offspring with the A/A genotype. The higher dopamine levels in the nucleus accumbens corresponded with higher maternal licking provisioning from postnatal days 2-9. We also discovered and validated several new variants that were predicted by our systematic analysis.

CONCLUSION

Our findings suggest that genetic variation influences the relationship between early-life maternal care received and the dopaminergic system of the maternal brain, which can indirectly influence later-life maternal care provisioning.

The reproductive stress hypothesis

In this paper, we propose the reproductive stress hypothesis that describes the pregnant females response to reproductive events based upon the activation of the hypothalamic–pituitary–adrenal axis and sympathetic adrenomedullary system. The main components of the reproductive stress hypothesis can be summarized as follows: (1) events unique to reproduction including empathema, pregnancy, parturition and lactation cause non-specific responses in females, called active reproductive stress; (2) the fetus is a special stressor for pregnant females where endocrine hormones, including corticotropin-releasing hormones and fetal glucocorticoids secreted by the fetus and placenta, enter the maternal circulatory system, leading to another stress response referred to as passive reproductive stress and (3) response to uterine tension and intrauterine infection is the third type of stress, called fetal intrauterine stress. Appropriate reproductive stress is a crucial prerequisite in normal reproductive processes. By contrast, excessive or inappropriate reproductive stress may result in dysfunctions of the reproductive system, such as compromised immune function, leading to susceptibility to disease. The novel insights of the reproductive stress hypothesis have important implications for deciphering the pathogenesis of certain diseases in pregnant animals, including humans, which in turn may be applied to preventing and treating their occurrence.

Positive Maternal Mental Health, Parenting, and Child Development

While maternal mental health is an important influence on child development, the existing literature focuses primarily on negative aspects of maternal mental health, particularly symptoms of depression, anxiety, or states of distress. We provide a review of the evidence on the potential importance of positive mental health for both mother and child. The evidence suggests that positive mental health is a distinct construct that is associated with improved birth outcomes and potentially with specific forms of parenting that promote both academic achievement and socioemotional function. We review studies that provide a plausible biological basis for the link between positive mental health and parenting, focusing on oxytocin-dopamine interactions. We caution that the evidence is largely preliminary and suggest directions for future research, noting the importance of identifying the operative dimensions of positive maternal mental health in relation to specific outcomes. We suggest that the inclusion of positive maternal mental health provides the potential for a more comprehensive understanding of parental influences on child development.

Dissecting maternal care: Patterns of maternal parenting in a prospective cohort study

Parental care has a strong impact on neurodevelopment and mental health in the offspring. Although numerous animal studies have revealed that the parental brain is a highly complex system involving many brain structures and neuroendocrine systems, human maternal parenting as a multidimensional construct with cognitive, emotional, and behavioural components has not been characterised comprehensively. This unique multi-method analysis aimed to examine patterns of self-reported and observed parenting from 6 to 60 months postpartum in a cohort of 496 mothers (mean maternal age = 32 years). Self-report questionnaires assessed motivational components of mothering, parenting stress, parenting-related mood, maternal investment, maternal parenting style, mother-child relationship satisfaction, and mother-child bonding at multiple time points. Observed parenting variables included the Ainsworth Sensitivity Scales at 6 and 18 months, the Behavioral Evaluation Strategies Taxonomies at 6 months, an Etch-A-Sketch cooperation task at 48 months, and the Parent-Child Early Relationship Assessment at 60 months. To examine whether different latent constructs underlie these measures of maternal parenting, we conducted an exploratory factor analysis. Self-report measures of parenting correlated only weakly with behavioural observations. Factor analysis on a subsample (n = 197) revealed four latent factors that each explained from 7% to 11% of the variance in the data (32% total variance explained). Based on the loadings of the instruments, the factors were interpreted as: Supportive Parenting, Self-Enjoyment Parenting, Overwhelmed Parenting, and Affectionate Parenting. These factor scores showed specific associations with maternal education and depressive symptoms, as well as with child outcomes, including maternally reported internalising and externalising behavioural problems, school readiness, and child-reported symptoms of mental health. These findings parallel the complexity of the parental brain, suggesting that maternal parenting consists of multiple components, each of which is associated with different maternal characteristics and child outcomes.

The maternal reward system in postpartum depression

The experience of motherhood is most often emotionally positive and rewarding, but for many new mothers suffering from postpartum depression (PPD), this is not the case. Preclinical and clinical research has sought to uncover brain changes underlying PPD in order to gain a better understanding of how this disorder develops. This review focuses on the mesolimbic dopamine system, particularly the ventral tegmental area-nucleus accumbens pathway which has been implicated in the regulation of critical functions disrupted in PPD including mood, motivation, and mothering. Specifically, we discuss normative changes in the mesolimbic system during motherhood in both rodents and humans and how these are impacted in PPD. We also consider modulation of mesolimbic dopamine by the hypothalamic neuropeptide oxytocin and how oxytocin-dopamine interactions regulate mood and mothering during the postpartum period. In addition to providing an overview of reward mechanisms in PPD, our goal is to highlight open questions which warrant further research.

Role of oxytocin in parental behaviour

Both animal and human studies have provided conclusive evidence that oxytocin (OXT) acts in the brain (eg, medial preoptic area, ventral tegmental area, nucleus accumbens) to promote parental behaviour under different reproductive and physiological conditions. OXT appears to accelerate and strengthen the neural process that makes newborns attractive or rewarding. Furthermore, OXT reduces stress/anxiety and might improve mood and well being, resulting in indirect benefits for parents. However, OXT also plays a role in the development of species reproductive and social strategies, making some species or individuals more prone to display caring activities in nonreproductive contexts. There are important differences in the development of the OXT system and its regulation by gonadal hormones that can make individuals or species very different. Those intra- and interspecific differences in the OXT system have been associated with differences in parental behaviour. For example, differences in OXT levels in body fluids and genetic variants for the OXT and OXT receptor genes have been associated with variability in parental mood and behaviour in humans. Thus, OXT has received much attention as a potential therapeutic agent for affective, emotional and behavioural problems. Despite many preliminary studies indicating promising findings, several unknown aspects of the OXT system remain to be addressed before we can achieve a complete understanding of its function in the brain. The enormous interest that this area of study has attracted in the last decade will likely continually contribute to advancing our understanding of the role of OXT in parental behaviour and other behavioural and physiological functions.

The influence of offspring, parity, and oxytocin on cognitive flexibility during the postpartum period

Pregnancy and the postpartum period are times of profound behavioral change including alterations in cognitive function. This has been most often studied using hippocampal-dependent tasks assessing spatial learning and memory. However, less is known about the cognitive effects of motherhood for tasks that rely on areas other than the hippocampus. We have previously shown that postpartum females perform better on the extradimensional phase of an attentional set shifting task, a measure of cognitive flexibility which is dependent on the medial prefrontal cortex (mPFC). The present experiments aimed to extend this work by examining the importance of postpartum stage as well as offspring and parity in driving improved mPFC cognitive function during motherhood. We also examined whether the neuropeptide oxytocin, which plays a role in regulating numerous maternal functions, mediates enhanced cognitive flexibility during motherhood. Our results demonstrate that compared to virgin females, cognitive flexibility is enhanced in mothers regardless of postpartum stage and is not affected by parity since both first (primiparous) and second (biparous) time mothers showed the enhancement. Moreover, we found that improved cognitive flexibility in mothers requires the presence of offspring, as removal of the pups abolished the cognitive enhancement in postpartum females. Lastly, using an oxytocin receptor antagonist, we demonstrate that oxytocin signaling in the mPFC is necessary for the beneficial effects of motherhood on cognitive flexibility. Together, these data provide insights into the temporal, experiential and hormonal factors which regulate mPFC-dependent cognitive function during the postpartum period.