State attachment moderates the maternal-related neural responses to infant faces

Oxytocin-Receptor Gene Modulates Reward-Network Connection and Relationship with Empathy Performance

Introduction

Empathy traits are highly heritable and linked with reward processing. It is implicated that common variations of the oxytocin-receptor gene (OXTR) play a modulatory effect on empathic performance. However, it is unclear about the neural substrates underlying the modulatory effect of the OXTR genotype on empathic performance. This study aimed to characterize the modulatory effect of common OXTR variations on reward-circuitry function and its relationship with empathy.

Methods

Based on the seed of the nucleus accumbens (NAcc; a key hub of reward circuitry), we examined differences in spontaneous local activity and functional connectivity between OXTR rs2268493 genotype groups and their relationship with empathic performance among 402 high-homogeneity participants.

Results

Comparing with C carriers (CC/CT) group, the individuals with the rs2268493 TT genotype exhibited lower functional connectivity of the right NAcc with the medial prefrontal cortex (mPFC) and inferior frontal gyrus. Similarly lower functional connectivity was found between the left NAcc and mPFC. Consequently, no significant difference was found in the spontaneous local activity of NAcc.

Discussion

Our findings suggested that common OXTR variations have a modulatory effect on the connection of the NAcc with the hub of empathic networks (mPFC and IFG), which may provide insight on the neural substrate underlying the modulatory effect of OXTR on empathic behavior.

Adult attachment style moderates the effect of oxytocin on neural responses to infant emotional faces

Oxytocin (OT) is known for its positive influence on maternal motivation and behavior, however, the effects of intranasal oxytocin (IN-OT) on neural activity during the perception of infant stimuli are often inconsistent. These discrepancies further reveal the need to take into account individual differences in IN-OT research. The present study aims to examine whether the effects of IN-OT on maternal-related neural responses to infant faces were moderated by participants' attachment style. Using a between-groups, double-blind, placebo-controlled design, 65 nulliparous females were randomly assigned to groups receiving a single dose of 24 IU oxytocin or a placebo via intranasal administration. The neural responses of participants were assessed during a facial recognition task with joy, neutral, and crying infant faces. The results indicated that females with high levels of attachment anxiety exhibited decreased right amygdala activity in response to infant joy faces and decreased bilateral insula activity in response to infant crying faces following IN-OT. Meanwhile, IN-OT enhanced bilateral amygdala and left inferior orbital frontal cortex (OFC) activity in response to infant crying faces in females with high levels of attachment avoidance. In addition, some beneficial effects of IN-OT were also observed in females with low levels of attachment avoidance or anxiety. Our findings demonstrated that the beneficial effects of IN-OT on neural responses to infant faces may depend on individual differences in adult attachment style, thereby contributing to our understanding of the role of OT in maternal caregiving.

Secure Attachment Priming Amplifies Approach Motivation for Infant Faces Among Childless Adults

Existing studies have indicated that priming secure attachment alters adults' neural responses to infant faces. However, no study has examined whether this effect exists for motivational behavioral responses, and none of the previous studies included adult faces as a baseline to determine whether the security prime enhances responses to human faces in general or infant faces alone. To address this limitation, the current study recruited 160 unmarried and childless adults in the first phase, and all of them completed a battery of questionnaires, including the Interest in Infants, the Experiences in Close Relationships (ECR), and State Adult Attachment Measure (SAAM). A week later, after priming, 152 (76 security-primed vs. 76 neutrally primed) participants completed the SAAM and a behavioral program assessing their motivational responses to both adult and infant faces (i.e., liking, representational, and evoked responses). A manipulation check showed that the security prime was effective. Then, generalized linear mixed-effects models (GLMMs) showed that security priming enhances adults' liking, representational, and evoked responses (three components of the motivational system) only to infant faces and not to adult faces. Moreover, hierarchical regression analysis indicated that, even after security priming, there was a substantial linear relationship between positive motivation toward infant faces and the state of adult secure attachment. In summary, this study demonstrated for the first time that promoting the state of adult secure attachment can effectively enhance the effect size of the baby face schema. The current results were interpreted according to Bowlby's view of the attachment behavioral system.