Evolving object concepts in the adult brain: An electrophysiological investigation.

This study investigated how the gradual acquisition of object meaning influences different phases of object recognition. Using an interleaved learning and testing procedure, participants were repeatedly exposed to unfamiliar, rare objects while learning about their meaning and function. Across multiple test sessions, event-related brain potentials (ERPs) were recorded to examine changes in early perceptual processing (P1) and later integrative phases of object recognition (N400, late positive complex/LPC) for initially unfamiliar versus well-known objects.

Beyond defense: microbial modifications of plant specialized metabolites alter and expand their ecological functions.

Plant specialized metabolites (PSMs) are compounds that are not involved in primary metabolism but instead confer other roles for the plant host, often related to ecological interactions. In the field of plant-microbe interactions, many PSMs have traditionally been considered for their roles in shaping interactions with pathogens. However, it is increasingly clear that 'defensive' PSMs have broader functions in regulating assembly and functions of plant-associated microbes, a phenomenon that is best studied in the rhizosphere.

Constraints on multi-item working memory access: performance costs and retrieval dynamics.

To support goal-directed behavior, working memory (WM) must flexibly access relevant information. While the mechanisms underlying single-item WM access are comparatively well-studied, less is known about the principles governing multi-item access. Some studies have suggested that dual-item retrieval can be as efficient as single-item access, but it remains unclear whether this reflects reduced inhibitory demands or truly parallel, cost-free retrieval.

Deterministic colonization arises early during the transition of soil bacteria to the phyllosphere and is shaped by plant-microbe interactions.

Background: Upon seed germination, soil bacteria are activated to transition to the plant and eventually colonize mature tissues like leaves. These bacteria are poised to significantly influence plant health, but we know little about their colonization routes. We studied the mechanisms of the transition of soil bacteria to germinating plants and leaves using an in-planta isolation approach and by experimentally manipulating inoculation times.

Glucosinolate structural diversity shapes recruitment of a metabolic network of leaf-associated bacteria.

Host defenses can have broader ecological roles, but how they shape natural microbiome recruitment is poorly understood. Aliphatic glucosinolates (GLSs) are secondary defense metabolites in Brassicaceae plant leaves. Their genetically defined structure shapes interactions with pests in Arabidopsis thaliana leaves, and here we find that it also shapes bacterial recruitment.

Working memory gating mechanisms explain developmental change in rule-guided behavior.

Cognitive control requires choosing contextual information to update into working memory (input gating), maintaining it there (maintenance) stable against distraction, and then choosing which subset of maintained information to use in guiding action (output gating). Recent work has raised the possibility that the development of rule-guided behavior, in the transition from childhood to adolescence, is linked specifically to changes in the gating components of working memory (Amso, Haas, McShane, & Badre, 2014). Given the importance of effective rule-guided behavior for decision making in this developmental transition, we used hierarchical rule tasks to probe the precise developmental dynamics of working memory gating.

"Trick or treat": the influence of incentives on developmental changes in feedback-based learning.

Developmental researchers have suggested that adolescents are characterized by stronger reward sensitivity than both children and younger adults. However, at this point, little is known about the extent to which developmental differences in incentive processing influence feedback-based learning. In this study, we applied an incentivized reinforcement learning task, in which errors resulted in losing money (loss condition), failure to gain money (gain condition), or neither (no-incentive condition).

Executive control training from middle childhood to adolescence.

Executive functions (EFs) include a number of higher-level cognitive control abilities, such as cognitive flexibility, inhibition, and working memory, which are instrumental in supporting action control and the flexible adaptation changing environments. These control functions are supported by the prefrontal cortex and therefore develop rapidly across childhood and mature well into late adolescence. Given that executive control is a strong predictor for various life outcomes, such as academic achievement, socioeconomic status, and physical health, numerous training interventions have been designed to improve executive functioning across the lifespan, many of them targeting children and adolescents.

The FN400 is functionally distinct from the N400.

The FN400 refers to the early midfrontally-distributed difference between ERPs elicited by old and new items, which operates in a way consistent with a neural marker of familiarity-based recognition. Double dissociations between the FN400 and a later ERP index of recollection provide some of the most compelling evidence in support of dual-process models to date. It has recently been claimed, however, that there is no evidence that the FN400 is functionally distinct from the N400 index of implicit semantic priming (Voss, J.

Punishment sensitivity modulates the processing of negative feedback but not error-induced learning.

Accumulating evidence suggests that individual differences in punishment and reward sensitivity are associated with functional alterations in neural systems underlying error and feedback processing. In particular, individuals highly sensitive to punishment have been found to be characterized by larger mediofrontal error signals as reflected in the error negativity/error-related negativity (Ne/ERN) and the feedback-related negativity (FRN). By contrast, reward sensitivity has been shown to relate to the error positivity (Pe).

Worse than feared? Failure induction modulates the electrophysiological signature of error monitoring during subsequent learning.

This study examined how self-relevant failure influences error monitoring--as reflected in the error-related negativity (Ne/ERN) --and behavioral adaptation during subsequent feedback-based learning. We applied two phases (pre- and posttest) of a probabilistic learning task. Between pre- and posttest, participants were assigned to one of two groups receiving either failure feedback or no feedback during a visual search task described as diagnostic of intellectual abilities.