Ocean radiocarbon (14C) is a proxy for air-sea exchange, vertical and horizontal mixing, and water mass identification. Here, we present five pre- to post-bomb coral Δ14C records from West Flower Garden Bank and Santiaguillo reefs in the Gulf of Mexico, Boca de Medio, and Isla Tortuga near the Cariaco Basin north of Venezuela. To assess basin-wide Δ14C variability, we compiled the Atlantic Ocean reef-building surface coral Δ14C records (24 corals and 28 data sets in total) with these new records. Cumulatively, the Δ14C records, on their independent age models, reveal the onset of post-bomb Δ14C trends in 1958 ±1 to 2 years. A general decrease in maximum Δ14C values occurs with decreasing latitude reflecting the balance between air-sea gas exchange and surface water residence time, vertical mixing, and horizontal advection. A slightly larger atmospheric imprint in the northern sites and relatively greater vertical mixing and/or advection of low-14C waters influence the southern Caribbean and eastern Atlantic sites. The eastern Atlantic sites, due to upwelling, have the lowest post-bomb Δ14C values. Equatorial currents from the eastern Atlantic transport low Δ14C water towards the western South Atlantic and southern Caribbean sites. Decadal Δ14C averages for the pre-bomb interval (1750–1949) for the low latitude western Atlantic are relatively constant within analytical (3–5‰) and chronological uncertainties (∼1–2 years) due to mixing and air-sea exchange. The compiled Δ14C records provide updated regional marine Δ14C values for marine reservoir corrections.

Callous-unemotional (CU) traits are early-emerging personality features characterized by deficits in empathy, concern for others, and remorse following social transgressions. One of the interpersonal deficits most consistently associated with CU traits is impaired behavioral and neurophysiological responsiveness to fearful facial expressions. However, the facial expression paradigms traditionally employed in neuroimaging are often ambiguous with respect to the nature of threat (i.e., is the perceiver the threat, or is something else in the environment?). In the present study, 30 adolescents with varying CU traits viewed fearful facial expressions cued to three different contexts (“afraid for you,” “afraid of you,” “afraid for self”) while undergoing functional magnetic resonance imaging (fMRI). Univariate analyses found that mean right amygdala activity during the “afraid for self” context was negatively associated with CU traits. With the goal of disentangling idiosyncratic stimulus-driven neural responses, we employed intersubject representational similarity analysis to link intersubject similarities in multivoxel neural response patterns to contextualized fearful expressions with differential intersubject models of CU traits. Among low-CU adolescents, neural response patterns while viewing fearful faces were most consistently similar early in the visual processing stream and among regions implicated in affective responding, but were more idiosyncratic as emotional face information moved up the cortical processing hierarchy. By contrast, high-CU adolescents’ neural response patterns consistently aligned along the entire cortical hierarchy (but diverged among low-CU youths). Observed patterns varied across contexts, suggesting that interpretations of fearful expressions depend to an extent on neural response patterns and are further shaped by levels of CU traits.

Alterations in reinforcement-based decision making may be associated with increased psychiatric vulnerability in children who have experienced maltreatment. A probabilistic passive avoidance task and a model-based functional magnetic resonance imaging analytic approach were implemented to assess the neurocomputational components underlying decision making: (a) reinforcement expectancies (the representation of the outcomes associated with a stimulus) and (b) prediction error signaling (the ability to detect the differences between expected and actual outcomes). There were three main findings. First, the maltreated group (n = 18; mean age = 13), relative to nonmaltreated peers (n = 19; mean age = 13), showed decreased activity during expected value processing in a widespread network commonly associated with reinforcement expectancies representation, including the striatum (especially the caudate), the orbitofrontal cortex, and medial temporal structures including the hippocampus and insula. Second, consistent with previously reported hyperresponsiveness to negative cues in the context of childhood abuse, the maltreated group showed increased prediction error signaling in the middle cingulate gyrus, somatosensory cortex, superior temporal gyrus, and thalamus. Third, the maltreated group showed increased activity in frontodorsal regions and in the putamen during expected value representation. These findings suggest that early adverse environments disrupt the development of decision-making processes, which in turn may compromise psychosocial functioning in ways that increase latent vulnerability to psychiatric disorder.

While maltreatment is known to impact social and emotional functioning, threat processing, and neural structure, the potentially dimorphic influence of sex on these outcomes remains relatively understudied. We investigated sex differences across these domains in a large community sample of children aged 10 to 14 years (n = 122) comprising 62 children with verified maltreatment experience and 60 well-matched nonmaltreated peers. The maltreated group relative to the nonmaltreated comparison group exhibited poorer social and emotional functioning (more peer problems and heightened emotional reactivity). Cognitively, they displayed a pattern of attentional avoidance of threat in a visual dot-probe task. Similar patterns were observed in males and females in these domains. Reduced gray matter volume was found to characterize the maltreated group in the medial orbitofrontal cortex, bilateral middle temporal lobes, and bilateral supramarginal gyrus; sex differences were observed only in the supramarginal gyrus. In addition, a disordinal interaction between maltreatment exposure and sex was found in the postcentral gyrus. Finally, attentional avoidance to threat mediated the relationship between maltreatment and emotional reactivity, and medial orbitofrontal cortex gray matter volume mediated the relationship between maltreatment and peer functioning. Similar mediation patterns were observed across sexes. This study highlights the utility of combining multiple levels of analysis when studying the “latent vulnerability” engendered by childhood maltreatment and yields tentative findings regarding a neural basis of sex differences in long-term outcomes for maltreated children.