Alterations in adolescent dopaminergic systems as a function of early mother-toddler attachment: A prospective longitudinal examination

Secure attachment to caregiver prevents adult depressive symptoms in a sex-dependent manner: A translational study

Although clinically relevant, evidence for a protective effect of early secure attachment against the development of depressive symptoms in adulthood is still inconsistent. This study used a translational approach to overcome this limitation. The analysis of a non-clinical adult population revealed a moderating effect of secure attachment on depressive symptoms in women only. Thus, we tested the causal link between early attachment with caregiver and adult depressive-like phenotypes in a mouse model of early adversities that is especially effective in females. Repeated cross fostering (RCF) in the first postnatal days prevented the development of pups' secure attachment with the caregiver as tested in a rodent version of the "strange situation"-the standard human test-induced depressive-like behaviors and altered activity of the ventral tegmental area dopamine neurons in adulthood. Finally, a stable alternative caregiver during the RCF experience prevented all these effects, modeling human "earned attachment."

Neural correlates of attachment in adolescents with trauma: a preliminary study on frustrative non-reward

Despite the proposed early life origins of attachment style and its implications for risk for psychopathology, little is known about its neurodevelopmental course. Adolescence represents a key transition period when neural substrates of emotion regulation and reward undergo dramatic maturational shifts. Thus, maladaptive coping strategies associated with insecure attachment styles may have an exaggerated effect during adolescence. The current study, therefore, examined the neural correlates of insecure attachment in a diverse sample of adolescents using a frustrative non-reward task (i.e. repeatedly being denied an expected reward). Although there were no significant interactions in the whole-brain activation averaged over the course of the task, the use of complementary analytic approaches (connectivity, change in activation over the course of the task) revealed widespread alterations associated with avoidant attachment during the immediate reaction to, and ensuing recovery from, being denied a reward. Most strikingly, increased avoidant attachment, adjusting for anxious attachment, predicted functional connectivity and change in activity over time in amygdala-prefrontal and frontostriatal networks to reward blocked vs received trials. These patterns were in the opposite direction compared to those exhibited by adolescents lower in avoidant attachment. The findings suggest that negative emotional experiences, such as receiving frustrating feedback, may be uniquely aversive internal experiences for avoidantly attached adolescents and provide preliminary evidence that early coping strategies may persist into adolescence in the form of altered emotion- and reward-related neural patterns.

Polygenic risk for traumatic loss-related PTSD in US military veterans: Protective effect of secure attachment style

OBJECTIVES

To examine whether attachment style moderates the relationship between polygenic risk scores (PRS) for posttraumatic stress disorder (PTSD) re-experiencing (PTSDREX) symptoms and the severity of and positive screen for traumatic loss-related PTSD.

METHODS

Data were analysed from 631 US veterans who endorsed 'unexpected death of a loved one' as their 'worst' traumatic event. Multivariable models evaluated the association between PRS for PTSDREX, attachment style, and their interaction in predicting severity and positive screen for PTSD. A gene enrichment analysis was conducted to identify possible molecular mechanisms underlying the association between PTSDREX PRS and PTSD.

RESULTS

PTSDREX PRS (β = 0.17; odds ratio [OR] = 1.85), attachment style (β= -0.33; OR = 0.14), and PTSDREX PRS × attachment style interaction (β= -0.12; OR = 0.53) were significant predictors of the severity and positive screen for PTSD. The most significant gene set detected was the gene ontology (GO) cellular component podosome set (GO:0002102, p < 3.95 × 10-5).

CONCLUSIONS

Having a secure attachment style may help mitigate polygenic risk for developing traumatic loss-related PTSD in US veterans. Podosomes, which are implicated in inflammatory and neuroplasticity processes, may contribute to the genetic liability to developing loss-related PTSD. Psychological treatments targeting attachment security may help mitigate increased polygenic risk for loss-related PTSD in this population.

Early life adversity affecting the attachment bond alters ventral tegmental area transcriptomic patterning and behavior almost exclusively in female mice

Early life experiences that affect the attachment bond formation can alter developmental trajectories and result in pathological outcomes in a sex-related manner. However, the molecular basis of sex differences is quite unknown. The dopaminergic system originating from the ventral tegmental area has been proposed to be a key mediator of this process. Here we exploited a murine model of early adversity (Repeated Cross Fostering, RCF) to test how interfering with the attachment bond formation affects the VTA-related functions in a sex-specific manner. Through a comprehensive behavioral screening, within the NiH RDoC framework, and by next-generation RNA-Seq experiments, we analyzed the long-lasting effect of RCF on behavioral and transcriptional profiles related to the VTA, across two different inbred strains of mouse in both sexes. We found that RCF impacted to an extremely greater extent VTA-related behaviors in females than in males and this result mirrored the transcriptional alterations in the VTA that were almost exclusively observed in females. The sexual dimorphism was conserved across two different inbred strains in spite of their divergent long lasting consequences of RCF exposure. Our data suggest that to be female primes a sub-set of genes to respond to early environmental perturbations. This is, to the best of our knowledge, the first evidence of an almost exclusive effect of early life experiences on females, thus mirroring the extremely stronger impact of precocious aversive events reported in clinical studies in women.