Developmental psychobiology最新文献

There are competing theoretical hypotheses regarding the consequences of early adversity, such as childhood maltreatment, for individuals’ autonomic nervous system activity. Research examining potential implications of child maltreatment for sympathetic nervous system activity, specifically, is scarce. In this preregistered study, we examined whether childhood maltreatment history is associated with pregnant adults’ sympathetic responses to different stressors. This population is particularly relevant, given potential intergenerational consequences of pregnant individuals’ physiological responses to stress. Pregnant women's (N = 162) electrodermal levels were recorded while completing the Trier Social Stress Test (TSST), which elicits social-evaluative threat, and while watching a video of an unfamiliar infant crying, which was intended to activate the attachment system. Pregnant women's retrospective reports of childhood maltreatment were negatively associated with their electrodermal reactivity to the TSST and to the video of the infant crying. Follow-up analyses indicated that these associations were specific to reported experiences of childhood abuse and not childhood neglect. Altogether, these findings indicate that self-reported childhood maltreatment experiences, and childhood abuse in particular, may result in blunted activity of the sympathetic nervous system in response to multiple types of stressors.

The postnatal environment is challenging for the preterm neonate with exposure to hypoxic and excitotoxic events, amplified by premature loss of placentally derived neurosteroids. Between preterm birth and term equivalent age (TEA), cerebellar development continues despite these challenges. We hypothesize that neurosteroid replacement therapy during this time will support optimal cerebellar development. Guinea pig sows delivered at term (∼69 days gestation) or were induced to deliver preterm (∼62 days), with preterm pups receiving ganaxolone or vehicle until TEA. Postnatal assessments comprised salivary cortisol (corrected postnatal age [CPA] 0, 7, 38), behavioral analysis (CPA7, 38), and tissue collection (CPA0 and CPA40). Neurodevelopmental markers (MBP, Olig2, and NeuN) were assessed in the cerebellum by immunohistochemistry, whereas RT-PCR was utilized to investigate key inhibitory/excitatory pathways and oligodendrocyte lineage markers. Following preterm birth, there was evidence of a hyperactive phenotype, increased salivary cortisol concentrations, and impaired myelination and oligodendrocyte maturation at the protein level. mRNA expressions of key inhibitory/excitatory pathways and myelin stability were also altered following preterm birth. Importantly, we showed that neurosteroid replacement therapy returns cerebellar development and behavior toward a term-like phenotype. Therefore, ganaxolone may reduce the vulnerability of the cerebellum to postnatal challenges arising from preterm birth.

Recent research has highlighted cerebellar involvement in cognition and several psychiatric conditions such as mood and anxiety disorders and schizophrenia. Attention-deficit/hyperactivity disorder and autism spectrum disorder have been linked to reduced cerebellar volume as well. Cerebellar alterations are frequently present after early adversity in humans and animals, but a systematic integration of results is lacking. To this end, a systematic literature search was conducted in PubMed, Web of Science, and EBSCO databases using the keywords “early adversity OR early life stress” AND “cerebellum OR cerebellar.” A total of 45 publications met the inclusion criteria: 25 studies investigated human subjects and 20 reported results from animal models. Findings in healthy subjects show bilateral volume reduction and decreased functional connectivity within the cerebellum and between the cerebellum and frontal regions after adversity throughout life, especially when adversity was assessed with the Childhood Trauma Questionnaire. In clinical populations, adults demonstrate increased cerebellar volume and functional connectivity after adversity, whereas pediatric patients show reduced cerebellar volume. Animal findings reveal cerebellar alterations without necessarily co-occurring pathological behavior, highlighting alterations in stress hormone receptor levels, cell density, and neuroinflammation markers. Cerebellar alterations after early adversity are robust findings across human and animal studies and occur independent of clinical symptoms.

The real world is full of noise and constantly overlapping sounds. However, our auditory system provides a solution to this, that is, the continuity illusion; when we hear a sound stream that is partially replaced by high-level noise, we can restore missing sound information and “fill in” the information as if it were smooth and continuous even against a background of noise. In the present study, we tested the preferences for familiar and novel melodies of 8-month-old infants after a 2-month memory retention interval following 1-week exposure to a specific melody. A preference for familiarity was seen not only when the melody was presented intact but also when it was periodically replaced by high-level noise, which elicits the continuity illusion in adults (Experiment 1). However, a trend toward preference for a novel melody was observed for stimuli periodically replaced by low-level noise that did not satisfy the ecological constraints for the elicitation of the illusion (Experiment 2). For the first time, this study showed that infants as young as 8 months of age are susceptible to the auditory continuity illusion. The study also revealed that the infants could recognize the melody they heard 2 months previously.

The opinions of peers are among the most potent factors influencing human decision-making. Research conducted in Western societies suggests that individuals become more resistant to peer influence from late adolescence to adulthood. It is unknown whether this developmental trajectory is universal across cultures. Through two cross-national studies, we present consistent self-report and behavioral evidence for culturally distinct developmental trajectories of resistance to peer influence (RPI). Our findings from the US samples replicated prior findings that reported increasing RPI. Yet, data from the Chinese participants were better fitted using a nonlinear model, displaying a U-shaped trajectory with lowest RPI levels at around 20 years old. In contrast to the long-held belief that increasing RPI from adolescence to early adulthood is a universal developmental trait, we propose that this developmental trajectory may depend on cultural context.

There is emerging evidence that the endocannabinoid system (ECS) plays a significant role in the pathophysiology of many psychiatric disorders, including attention deficit hyperactivity disorder (ADHD). Increasing evidence suggests that a number of neurobiological correlates between endogenous cannabinoid function and cognitive dysfunction are seen in ADHD, making the ECS a possible target for therapeutic interventions. Cannabis use and cannabis use disorder are more prevalent in individuals with ADHD, compared to the general population, and there is growing popular perception that cannabis is therapeutic for ADHD. However, the relationship between cannabis use and ADHD symptomology is poorly understood. Further understanding of the role of the ECS in ADHD pathophysiology and the molecular alterations that may be a target for treatment is needed. To further the science on this emerging area of research, this scoping review describes the preclinical and clinical evidence seeking to understand the relationship between the ECS and ADHD.