Adaptive behavior requires control over automatic tendencies to approach reward and avoid threat. Dysregulation of this control characterizes disorders such as anxiety or addiction, yet the underlying neural mechanisms remain unclear. Here, we investigated circuits engaged during approach-avoidance control using fMRI with eye-tracking, and behavioral measures. Forty participants (22 females) completed an approach-avoidance conflict task with free- and forced-choice trials. Each trial comprised anticipation, response (using a joystick to approach/obtain or avoid/forgo outcomes), and outcome phases. Before scanning, participants were instructed and experienced that conditioned stimuli (CS) predicted an aversive painful stimulation (avCS+), an appetitive monetary reward (appCS+), both outcomes (confCS+), or no outcome (neuCS-). Discordant responses (e.g., approaching avCS+) were slower than concordant responses (e.g., avoiding avCS+), confirming heightened control demands. Overcoming threat-driven avoidance specifically recruited the left inferior frontal gyrus (IFG), while suppressing reward-driven approach lacked distinct neural signatures. During anticipation, confCS+ and avCS+ showed overlapping activation in salience-control networks, including middle/anterior cingulate cortex (MCC/ACC), anterior insula, IFG, and ventral striatum (VS). Interestingly, confCS+ evoked threat-like anticipatory neurophysiological responses (pupil dilation; ACC/insula activation) but subsequently triggered reward-like approach behavior. Multivariate pattern and psychophysiological interaction analyses revealed that this dissociation was driven by differential encoding of upcoming responses in the VS during the anticipation phase and by altered functional coupling between the VS and the right temporoparietal junction (rTPJ). These findings indicate that motivational control prioritizes salience over valence and suggest a VS-rTPJ network for resolving approach-avoidance conflicts, offering novel insights into neural dynamics of flexible goal-directed behavior.Significance Statement This study advances our understanding of how the brain dynamically resolves conflicts between avoiding pain and obtaining monetary rewards. By measuring neural activity during approach-avoidance conflicts, our study identified overlapping neural circuits for threat and conflict processing (e.g., middle/anterior cingulate, ventral striatum). It revealed that threat-like neural responses to conflicting stimuli triggered approach behaviors resembling reward-motivated actions. Critically, connectivity between the ventral striatum and the temporoparietal junction predicted individual differences in conflict resolution, linking network-level interactions to adaptive behavioral control. These findings suggest that salience overrides valence in motivational control and motivate hypothesis-driven tests of network disruptions in psychiatric populations.
In the gig economy, the influence of algorithmic management pressure on gig workers' well-being has drawn increasing attention in both theoretical and practical contexts. Grounded in the conservation of resources theory, the study aims to explore the mechanisms linking algorithmic management pressure to three dimensions of gig workers' well-being, with a particular focus on the mediating role of avoidance job crafting. We conducted a three-wave survey with 321 ride-hailing drivers using an anonymous, structured questionnaire that measured algorithmic management pressure, avoidance job crafting, and well-being. We analyzed the data by using SPSS 26.0 and Mplus 8.30. Results show that algorithmic management pressure does not consistently undermine well-being outcomes. Specifically, by eliciting gig workers' avoidance job crafting, algorithmic management pressure exhibits a temporally positive relationship with aspects of their life well-being and workplace well-being. However, the hypothesis regarding the indirect effect of the pressure on psychological well-being through avoidance job crafting is not supported. Theoretical and practical implications are discussed.
Neighbor proximity triggers changes in light quality that regulate various developmental and physiological processes in plants. phytochrome B (phyB)-PHYTOCHROMEINTERACTING FACTOR 4 (PIF4) module serves as a central regulatory hub enabling plants to accurately perceive and respond to shade cues. Here, we identify B-box PROTEIN 5 (BBX5) as a positive regulator of shade avoidance. phyB interacts with BBX5 and promotes its protein stability. Conversely, the E3 ubiquitin ligase CONSTITUTIVELY PHOTOMORPHOGENICLY 1 (COP1) associates with and destabilizes BBX5 via the 26S proteasome system in shade. BBX5 binds to the PIF4 promoter to upregulate its expression during the early phase of shade exposure, and directly associates with the promoters of auxin biosynthetic and signaling genes YUCCA8 (YUC8) and INDOLE-3-ACETIC ACID INDUCIBLE 19 (IAA19) to activate their expression in shade. Our study reveals that BBX5 acts as a transcriptional activator of PIF4, YUC8 and IAA19 to promote plant growth and development in response to shade signals.
A 78-year-old woman had gluteal pain radiating to both lateral thighs and calves and progressive neurogenic claudication. Imaging revealed osteoporotic thoracolumbar compression fractures, L4 spondylolisthesis with severe L4-5 stenosis, and sagittal kyphosis. Spinopelvic parameters were not measured, owing to extreme forward-flexed posture. Given the high risk of instrumentation failure and complications, spinal cord stimulation (SCS) was selected after initiating osteoporosis therapy. The pain improved, with pain relief and ambulatory function maintained at 18 months without surgery. SCS may be an alternative to fusion in selected osteoporotic patients with severe sagittal imbalance and lumbar radiculopathy.
Anorexia nervosa (AN) involves extreme food restriction and body image disturbances, partly sustained by altered responses to food cues, including implicit and behavioral avoidance, especially toward high-calorie foods. We tested whether altering body ownership in virtual reality could modulate such biases. Female participants with restricting-subtype AN (AN-R; n = 29) and healthy controls (HC; n = 31) completed three sessions: a baseline and two full-body illusion (FBI) sessions in which they embodied slimmer or larger avatars than their own body size. Across sessions, they performed a binocular rivalry task and a food-specific approach-avoidance task with high- and low-calorie foods, together with body-size estimation and symptom measures. At baseline, AN-R participants showed greater perceptual salience and stronger avoidance of high-calorie foods than HC. Relative to the baseline, embodying a larger avatar attenuated avoidance in AN-R, whereas HC showed the opposite pattern. These findings suggest that the FBI can transiently modify implicit food-related avoidance in AN-R.
Type B ulnar polydactyly is a common congenital hand anomaly. Treatment options include suture ligation, vascular clip ligation and excision under local or general anaesthesia. However, the optimal treatment remains unclear, and evidence on parental perspectives is limited. This review investigated treatment outcomes for type B ulnar polydactyly, in combination with parental satisfaction and preferences. A systematic search of Embase, Pubmed, Medline, Web of Science and Cochrane Central Register of Controlled Trials was conducted up to March 2025 for studies reporting parental satisfaction with treatment outcome or aesthetic appearance, parental prioritizing factors or complications. Meta-analyses were performed on pooled parent-reported satisfaction scores and complication data. Fourteen studies, comprising 885 patients with 1279 supernumerary digits, met the inclusion criteria. Overall, parental satisfaction was high across all treatments. Excision under local anaesthesia resulted in significantly greater satisfaction on both treatment outcome and aesthetic appearance compared with suture ligation and excision under general anaesthesia. No parent-reported data were available on vascular clip ligation. Parents choosing suture ligation or excision under local anaesthesia mentioned avoiding anaesthesia risks and quick treatment as priorities, while parents selecting excision under general anaesthesia prioritized pain avoidance. The pooled complication rate was lowest for excision under local anaesthesia (0.01) and highest for suture ligation (0.16). Excision under local anaesthesia showed the best results regarding treatment of type B ulnar polydactyly, with the highest parental satisfaction outcomes and lowest complication rates. However, high parental satisfaction was observed in all treatment modalities and differences in outcomes were small. Parents primarily based their treatment choice on avoiding risks (with ligation or local anaesthesia) or avoiding pain (with general anaesthesia). Our results can be used for effective decision making.
Exposure to childhood trauma (CT) increases the risk of depression, yet it remains unclear how childhood trauma modulates the attentional processing of emotional information in individuals with depressive symptoms (DS). This study aimed to investigate the shared and distinct eye-tracking attentional profiles of individuals with DS, with and without a history of CT. A sample of 159 young adults (age range 18-24) was recruited and categorized into four groups: co-occurring childhood trauma and depressive symptoms (CT + DS, n = 32), childhood trauma only (CT, n = 24), depressive symptoms only (DS, n = 31), and healthy controls (Control, n = 72). Self-reported attentional biases were assessed using the Attention to Positive and Negative Information Scale (APNI). Visual attention was assessed using a free-viewing eye-tracking paradigm with four facial expressions (happy, sad, angry, neutral); indices included First Fixation Duration (FFD), Percentage of Fixation Duration (PFD), and Number of Revisits. Significant group differences were found for FFD (F = 5.15, p < .001) and PFD (F = 15.24, p < .001), and significant interaction was found for number of revisits (F = 20.60, p < .001). While the DS group exhibited a classic negative attentional bias (more revisits to angry and sad faces), the CT + DS group demonstrated a reversal, specifically avoiding sad faces, and the CT group showed avoidance of angry faces. The observed avoidance of sad faces might signal depressive vulnerability following childhood trauma, highlighting the need for trauma-stratified depression screening and personalized attention modification in early interventions.
It is often thought that Thomson's Violinist argument is only applicable before the point of viability. In this paper, I propose that this is not the case, offering a novel defense of post-viability abortion utilising Thomson's self-defense framework. I first set out Thomson's Violinist argument and how it interacts with viability. Then I defend the Invasiveness Claim: there is a stringent right not to have to go through childbirth (including the "safe removal procedures" of induction of labor and caesarian section) because of the level and nature of invasiveness. This is because unwanted childbirth can be seen as a harm in some ways akin to rape. Finally, I show that the Invasiveness Claim along with Thomson's view on self-defense leads to the conclusion that post-viability abortion is morally permissible. My conclusion is conditional: using a Thomsonian framework of abortion, if a third party may kill an innocent perpetrator in a case of "other-defense", then it is morally permissible for a pregnant person to choose to have an abortion (and a third party to provide abortion) to avoid having to give birth, even after the point of viability. This constitutes a significant moral defense of almost all post-viability abortions for those sympathetic to Thomson's defense of abortion and her view of self-defense, and one which I think is underexplored. There is much literature on abortion as self-defense to avoid pregnancy, but not much about abortion as self-defense to avoid childbirth, or about women having a stringent right not to undergo labor.
Human activities have significantly altered natural habitats, changing the behavior of many animals. As human encroachment on natural habitats increases, animals must adapt their behavior to couple with these rapid environmental changes. The landscape of fear (LOF) refers to prey perception of risk, which leads to behavioral adaptations throughout an animal's lifetime. Animals might choose habitats with lower potential energy intake and lower perceived risk over those with higher potential energy intake and higher perceived risk, thus trading off food quality for safety. Here, we investigate whether two endangered mammal species increase the frequency with which they use their travel routes as a navigation strategy to avoid human-influenced areas and traumatic-risk events. Thus, creating a habitual route system to avoid these events and human activities. Using GIS, primary movement data, and remote sensing, we demonstrated that two endangered species increase their use of habitual routes in landscapes where hunting by humans is present. This means using their LOF potentially to focus on signs of risky locations, and human activities, including hunting. These analytical approaches raise questions about whether some species opt for less demanding navigation strategies to balance their focus between navigation and monitoring for signals of risk.
This study aimed to explore the lived experiences of children who have undergone traumatic medical interventions, focusing on their emotional, behavioral, and psychosocial responses. A descriptive thematic qualitative design was employed. Semi-structured interviews were conducted with 15 children aged 7-18 who were recently hospitalized at a state hospital in Türkiye. Data were analyzed thematically using Deterding and Waters' flexible coding approach within a biopsychosocial trauma framework. Five core themes emerged: (1) Trauma Induced by Medical Interventions, (2) Re-experiencing, (3) Avoidant Attitudes, (4) Emotional and Bodily Responses, and (5) Psychosocial Adaptation Process. Children's trauma narratives revealed a complex interplay of procedural pain, fear, avoidance, emotional withdrawal, somatic distress, and the critical influence of age, sex, and relational support. Pediatric medical trauma extends beyond physical procedures, encompassing emotional, relational, and developmental dimensions. A trauma-informed, developmentally sensitive care approach that fosters emotional safety and empowers children is essential to promoting adaptive coping and preventing long-term distress. Integrating trauma-informed, developmentally sensitive care practices into pediatric settings can help nurses recognize behavioral and somatic indicators of distress, provide emotional safety, and foster resilience in hospitalized children.
Calcitonin gene-related peptide (CGRP) is a key mediator of migraine, but the mechanisms through which meningeal CGRP engages central circuits involved in the sensory and affective dimensions of migraine remain incompletely understood. Here, we tested if supradural CGRP is sufficient to induce migraine-like sensory and affective behaviors and if these effects are associated with sex-dependent changes in parabrachial-central amygdala (PB-CeA) signaling. Adult male and female C57BL/6J mice received supradural CGRP or vehicle. Behavioral testing, whole-cell patch-clamp recordings, and qPCR analyses were performed 3 h later. CGRP induced robust periorbital mechanical allodynia selectively in females, while hindpaw mechanical thresholds were reduced in both sexes, with a greater effect in females. CGRP also increased avoidance-like behavior in both sexes, reflected by decreased open-arm exploration in the elevated plus maze and decreased time spent in the light compartment of the light-dark box. Whole-cell patch-clamp recordings from neurons in the right latero-capsular central amygdala in CGRP-exposed mice revealed higher excitability and larger PB-evoked excitatory postsynaptic currents in females than males. Ex vivo bath application of the CGRP receptor antagonist CGRP₈₋₃₇ was used to test local CGRP receptor sensitivity and selectively decreased excitability and PB-evoked excitatory transmission in females, while paired-pulse ratio remained unchanged in both sexes. In addition, qPCR analysis identified region- and sex-dependent transcriptional changes after supradural CGRP, with the most consistent molecular effects observed in the right PBN and more limited changes in the right CeA. Together, these findings show that supradural CGRP is sufficient to produce sex-differentiated mechanical hypersensitivity and avoidance-like behavior and is associated with sex-dependent physiological and transcriptional changes, including a right-sided pattern of transcriptional effects. These results identify the PB-CeA pathway as a candidate substrate linking meningeal CGRP signaling to central mechanisms relevant to hypersensitivity and amygdala plasticity that is more pronounced in females.
Subsea power cables used to transport offshore wind-generated energy emit electromagnetic fields (EMFs) into the marine environment. These anthropogenic fields overlap with naturally occurring biotic and abiotic EMFs that elasmobranchs can detect and use for navigation, prey detection and predator avoidance. When egg-laying sites overlap with subsea cables, embryos may be chronically exposed to EMFs throughout development, yet the effects remain largely unknown. We compared the morphology and behaviour of thornback skate (Raja clavata) and small-spotted catshark (Scyliorhinus canicula) juveniles exposed to alternating current EMFs (1.8 and 4.6 μT) throughout embryogenesis, with an unexposed control group. In skates, tail length was significantly shorter (5.3%) in exposed individuals at both one and three months post-hatching, while in exposed sharks, the pectoral fins were 11.2% larger at birth, a transient effect that disappeared after one month. These results may indicate subtle changes in growth of EMF exposure. As tail/fin-to-body ratios were unchanged, the extremities could be proxy for overall differences in length, possibly obscured by postural variation. Activity levels and ventilation rates did not differ between treatments, nor were startle or avoidance responses observed following acute EMF exposure. However, sharks showed a significant difference in ventilation rate between 0.1 μT (background) and 10 μT, indicating EMF detection. We conclude that chronic exposure during embryogenesis causes subtle, species-specific growth effects without behavioural impairment. Although ecological relevance of these findings is unclear, it highlights the need for caution when extrapolating EMF sensitivity across elasmobranch species.
The Nova classification considers the purpose and degree of food processing to capture how recent changes in the food system may link with health. Its value for understanding diet-disease relationships is debated. However, reviews typically focus only on its value, or its limitations. Furthermore, by discussing the degree of processing only and not the purpose, or discussing processing in general, reviews of limitations do not address pitfalls of the Nova classification. This conflict and confusion stalls progress to improve public health. Therefore, this review aims to provide a balanced understanding, interpretation and utilisation of the Nova classification and purpose of food processing, with a critical evaluation of its potential value, of pitfalls largely overlooked to date with recommendations to avoid unintended consequences, and constructive reflections on a path forward. The Nova classification offers a framework linking upstream socioeconomic factors with downstream properties of available food, complementing existing food-based dietary guidance to improve access to healthy diets through food systems transformations. However, its practical application, narrative of intrinsic harm of ultra-processing, usage to guide diets in isolation, and overemphasis on mechanisms with weaker evidence are pitfalls that, whilst avoidable, can have unintended consequences. There is agreement on the need for food systems transformation to ensure access and affordability to healthy diets for all. For public health, the purpose behind food processing provides an understanding of systems drivers of food production and accessibility. This consideration can be reflected in policy to improve access to healthy diets, without necessarily explicit use of the Nova classification.
Despite its well-established benefits, breastfeeding practices differ across communities, and many women exhibit suboptimal practices due to cultural influences and limited access to accurate information. Nulliparous pregnant women, in particular, lack prior breastfeeding experience and are often strongly influenced by family members such as mothers-in-law. However, there is limited evidence on whether involving these influential family members in breastfeeding education can improve breastfeeding practices. This study evaluated the effectiveness of breastfeeding educational interventions delivered to pregnant women together with their mothers-in-law, and pregnant women alone versus pregnant women in routine care in rural Central Ethiopia. A community-based, three-arm, cluster randomized controlled trial was conducted among 510 pregnant women enrolled before 16 weeks of gestation. The study arms were: (1) pregnant woman with her mother-in-law, (2) pregnant woman alone, and (3) control group receiving routine care. Fifty-one non-adjacent clusters were randomly assigned using simple randomization. The intervention consisted of eight home-based educational sessions: six during pregnancy and two postpartum. Outcomes included pre-lacteal feeding, colostrum feeding, early initiation of breastfeeding, and exclusive breastfeeding. In the intervention groups (pregnant women and their mother-in-law paired, and pregnant women alone) there were significantly lower incidence of pre-lacteal feeding than pregnant women in the control group (9.1% and 11.4% vs. 19.8%, p = 0.011), and a higher incidence of colostrum feeding (92.7% and 90.4% vs. 81.4%, p = 0.004), early initiation of breastfeeding (80.4% and 72.5% vs. 53.3%, p < 0.001) and exclusive breastfeeding (80.9% and 74.3% vs. 59.9%, p < 0.001). Breastfeeding in both intervention groups have significant effect on breastfeeding practices; avoiding pre-lacteal feeding [RR = 2.17, 95%CI: (1.19, 3.85) and RR = 1.79(1.06, 2.86)], colostrum feeding [RR = 1.14(1.01, 1.29) and RR = 1.11(1.01, 1.23)], early initiation of breastfeeding [RR = 1.51(1.14, 1.99) and RR = 1.36(1.02, 1.82)], and exclusive breastfeeding [RR = 2.08(1.43, 3.03) and RR = 1.56(1.05, 2.33)] as compared to the control group. Involving mothers-in-law in breastfeeding educational interventions in addition to active interventions to pregnant women alone has broader practical implication for improving recommended breastfeeding practices. ClinicalTrials.gov identifier (NCT number): NCT06236412, January 23, 2024.
Bioremediation presents a promising technology for treating petroleum hydrocarbons contamination in groundwater. However, the conventional enrichment-based isolation method poses a critical bottleneck of laboratory-proven degradation efficiencies but poor field performance caused by the selective pressure during enrichment process. To address this, this study developed a novel bioremediation strategy based on single-cell screening, replacing conventional enrichment-based isolation, to obtain indigenous hydrocarbon-degrading bacteria from contaminated groundwater. By eliminating the enrichment step, the screening cycle was substantially shortened to only 5 days. Moreover, this approach avoids the selective pressure of artificial culture media, thereby enabling the isolation of indigenous strains with high growth and degradation efficiency directly in the original groundwater. Among five isolated strains, Sphingobium yanoikuyae demonstrated the highest degradation efficiency, reducing petroleum hydrocarbon concentrations from 29.0 ± 1.8 mg/L to 3.6 ± 1.6 mg/L within 8 days (87.6% removal). In a two-dimensional sandbox model, GFP-tagged S. yanoikuyae rapidly colonized the system and formed a stable bioreaction zone within 15 days, decreasing hydrocarbon concentration from 50 mg/L to 20 mg/L within two days. Field validation via a single in-situ injection confirmed successful colonization and bioreaction zone establishment within 30 days, achieving a reduction in total petroleum hydrocarbon concentration from 48 mg/L to 0.34 mg/L (>99% removal). No tailing effect was observed over 1-year continuous monitoring. This work establishes a bias-minimized screening paradigm that bridges the long-standing gap between laboratory-proven degradation efficiencies and field bioremediation performance.
Affiliate stigma occurs when care partners internalize stigma directed towards their loved ones. Care partners of people with epilepsy (PWE), defined as individuals who provide support, are at risk for distress, family dysfunction, and burden; yet, the multidimensional impact of affiliate stigma on family and emotional well-being remains understudied. This mixed-methods study examined associations among care partner burden, family functioning, and affiliate stigma, and explored care partners' experiences and support needs. Forty-eight care partners of PWE (mean age = 47.98 years, 77.1% female) completed affiliate stigma (Mak Affiliate Stigma Scale; affective, cognitive, behavioral domains), burden (Zarit Burden Interview), and family functioning (Family Assessment Device) measures. Multivariate regressions examined interrelationships, adjusting for care recipient age (pediatric vs. adult). A purposeful subsample (n = 7) completed qualitative interviews, analyzed using theory-informed deductive thematic analysis. Higher affiliate stigma was associated with greater burden and poorer family role functioning. When examined across the scale's subdomains, affective stigma uniquely predicted burden, whereas cognitive and behavioral stigma predicted family role functioning. Qualitative findings revealed that enacted and felt stigma contributed to distress (e.g., shame, anger), hypervigilance, and anticipation of worst-case scenarios, as well as adaptive (e.g., self-care, advocacy) and maladaptive (e.g., social avoidance, emotional withdrawal) coping. Stigma-related experiences strained relationships, engendered isolation, and contributed to unmet support needs. Affiliate stigma exerts a multidimensional impact on care partners' well-being and family functioning, reinforcing the need for care partner-focused interventions addressing affective, cognitive, and behavioral aspects of affiliate stigma in epilepsy care.
The students from key universities face a higher risk of depression and anxiety than those from non-key universities. However, the utilization rate of on-campus counseling services remains very low. Working from the theory of perceived affordances, this study investigates the reasons why some college students with emotional distress at a Chinese key university avoid using the provided on-campus psychological counseling services. This study employed Braun and Clarke's reflexive thematic analysis method to code and extract themes from the texts obtained through in-depth interviews. It was conducted at a key Chinese university, where 13 participants were recruited using purposive sampling and took part in interviews lasting between 30 min and two hours. The study revealed that perceived affordances of the campus mental health education and counseling center (MHECC) among this group of college students exhibited three characteristics: surveillant services, counseling without empathy, and cautious peer support. Although these negative perceived affordances of the MHECC may be inconsistent with its real affordances, they led this group of college students to make a decision to refuse help-seeking without accessing the counseling services. To enhance the usability of the MHECC, the perceived information regarding the Center's affordances should be optimized based on college students' experiences and cultural backgrounds.
Traditional online reinforcement learning (RL) systems operate by actively engaging with their environments to acquire data, with the goal of formulating an optimal policy that maximizes a predefined cumulative reward. However, in scenarios where cost and safety are paramount, the practicality of online RL is constrained. In response, offline RL emerges as a viable solution, leveraging previously amassed datasets to craft an effective policy without the need for ongoing interaction with the environment. An obstacle in offline RL lies in its tendency to overestimate the values of actions not adequately represented in the data, known as out-of-distribution (OOD) actions. While previous approaches have typically sought to enhance performance through increased algorithmic complexity, this article introduces a novel methodology that significantly improves the offline performance, with only minor additional memory cost. This study delves into the analysis of retaining high performance throughout the fully offline training. Since offline learning is unable to correct errors without interaction with the environment, it is highly dependent on the dataset. For example, a good policy can never be trained on a random dataset. On the other hand, even if an algorithm can give good performance temporarily, it will easily lead to OOD errors. Instead of resorting to complicated policy regularization, propose a simple center replacement approach that adjusts the offline dataset to suit the proposed algorithm, so that the OOD errors can be avoided, as well as improving the training performance. Our method introduces an adaptive regularization target that evolves with policy improvement, effectively relaxing the conservatism constraint over time without requiring online interaction.
A model for multiple-choice (MC) items based on signal detection theory (SDT), the MC-SDT model (DeCarlo, 2021a), follows from assumptions about perceptual and decision processes involved when examinees choose alternatives for MC items. The model can be expressed as a hierarchical model with an 'item-level', Level 1, and an 'examinee-level', Level 2. Here it is shown that cognitive diagnosis models (CDMs) can also be viewed as consisting of two levels, with the MC-SDT model serving as the first-level model, whereas the second-level model determines the type of CDM. Thus, the theory about how examinees make choices for MC items is unified across different CDMs. The resulting MC-SDT-CDM models are shown to be parsimonious sub-models of MC-CDMs. The models have straightforward interpretations (MC-SDT at Level 1), avoid estimation problems, and are useful for small sample sizes. The models are illustrated with an application to MC items from the TIMSS 2007 4th grade exam.
Through a structural priming paradigm, this ERP study investigated the abstraction of morphosyntactic representations and the neural mechanisms underlying the pre-activation of such representations to facilitate phrasal processing. Chinese verb phrases were constructed with a verb-object compound (VO compound, e.g., -to request a leave) and a position-flexible perfective aspect marker -le (V-O-le and V-le-O, e.g., both and mean requested a leave). By avoiding VO compound overlap and manipulating marker position congruence between the prime and target, the study assessed the conditions under which priming effects arise from the pre-activation of perfective representations. Grand-average ERPs indicated facilitation in both semantic (N400 reduction) and syntactic (P600 reduction) processing streams. Follow-up cluster analysis revealed these group-level effects to be artifacts of averaging across distinct subpopulations with different neurocognitive profiles. A P600-dominant group showed priming effects exclusively as modulation of the P600 component, reflecting a processing strategy focused on later syntactic reanalysis, whereas an N400-dominant group showed effects primarily in the N400 time window, indicating a strategy centered on earlier lexicosemantic integration. Further analyses within each subgroup revealed that the abstract representation of perfectivity was available at the phrasal level and that its activation was contingent on marker position within the phrase. The findings provide evidence not only for abstract morphosyntactic priming below the sentence level, but also for a functional N400/P600 trade-off in language processing, challenging unitary biphasic models and highlighting the need to incorporate systematic individual variation into the debate on syntactic versus semantic pathways of language comprehension.