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1.
JAMA Psychiatry ; 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39083325

RESUMO

Importance: Research on resilience after trauma has often focused on individual-level factors (eg, ability to cope with adversity) and overlooked influential neighborhood-level factors that may help mitigate the development of posttraumatic stress disorder (PTSD). Objective: To investigate whether an interaction between residential greenspace and self-reported individual resources was associated with a resilient PTSD trajectory (ie, low/no symptoms) and to test if the association between greenspace and PTSD trajectory was mediated by neural reactivity to reward. Design, Setting, and Participants: As part of a longitudinal cohort study, trauma survivors were recruited from emergency departments across the US. Two weeks after trauma, a subset of participants underwent functional magnetic resonance imaging during a monetary reward task. Study data were analyzed from January to November 2023. Exposures: Residential greenspace within a 100-m buffer of each participant's home address was derived from satellite imagery and quantified using the Normalized Difference Vegetation Index and perceived individual resources measured by the Connor-Davidson Resilience Scale (CD-RISC). Main Outcome and Measures: PTSD symptom severity measured at 2 weeks, 8 weeks, 3 months, and 6 months after trauma. Neural responses to monetary reward in reward-related regions (ie, amygdala, nucleus accumbens, orbitofrontal cortex) was a secondary outcome. Covariates included both geocoded (eg, area deprivation index) and self-reported characteristics (eg, childhood maltreatment, income). Results: In 2597 trauma survivors (mean [SD] age, 36.5 [13.4] years; 1637 female [63%]; 1304 non-Hispanic Black [50.2%], 289 Hispanic [11.1%], 901 non-Hispanic White [34.7%], 93 non-Hispanic other race [3.6%], and 10 missing/unreported [0.4%]), 6 PTSD trajectories (resilient, nonremitting high, nonremitting moderate, slow recovery, rapid recovery, delayed) were identified through latent-class mixed-effect modeling. Multinominal logistic regressions revealed that for individuals with higher CD-RISC scores, greenspace was associated with a greater likelihood of assignment in a resilient trajectory compared with nonremitting high (Wald z test = -3.92; P < .001), nonremitting moderate (Wald z test = -2.24; P = .03), or slow recovery (Wald z test = -2.27; P = .02) classes. Greenspace was also associated with greater neural reactivity to reward in the amygdala (n = 288; t277 = 2.83; adjusted P value = 0.02); however, reward reactivity did not differ by PTSD trajectory. Conclusions and Relevance: In this cohort study, greenspace and self-reported individual resources were significantly associated with PTSD trajectories. These findings suggest that factors at multiple ecological levels may contribute to the likelihood of resiliency to PTSD after trauma.

2.
Learn Mem ; 31(7)2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39084866

RESUMO

Incubation of craving is a phenomenon describing the intensification of craving for a reward over extended periods of abstinence from reinforcement. Animal models use instrumental markers of craving to reward cues to examine incubation, while human paradigms rely on subjective self-reports. Here, we characterize an animal-inspired, novel human paradigm that showed strong positive relationships between self-reports and instrumental markers of craving for favored palatable foods. Further, we found consistent nonlinear relationships with time since last consumption and self-reports, and preliminary patterns between time and instrumental responses. These findings provide a novel approach to establishing an animal-inspired human model of incubation.


Assuntos
Condicionamento Operante , Fissura , Autorrelato , Humanos , Fissura/fisiologia , Feminino , Masculino , Condicionamento Operante/fisiologia , Adulto Jovem , Adulto , Recompensa , Alimentos , Sinais (Psicologia) , Comportamento Alimentar/fisiologia , Adolescente , Fatores de Tempo
3.
Cognition ; 251: 105884, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39047582

RESUMO

Memories are not only stored for personal recall, but also to communicate knowledge to others in service of adaptive decision-making. Prior research shows that goals to share information can change which content is communicated in memory as well as the linguistic style embedded in this communication. Yet, little is known as to how communication-related alterations in memory narration drive differences of value processing in listeners. Here, we test how memory communication alters multi-featural recall for complex events and the downstream consequence on value estimations in naïve listeners. Participants recalled a memory of playing an exploratory videogame at a 24-h delay under instructions to either share (i.e., social condition) or recall (i.e., control condition) their memory. Sharing goals systematically altered the content and linguistic style of recall, such that narrators from the social condition were biased towards recall of non-episodic details and communicated their memories with more clout, less formality, and less authenticity. Across two independent samples of naïve listeners, these features differentially influenced value estimations of the video game. We found that greater clout was associated with greater enjoyment while listening to memories (hedonic value), and that greater inclusion of non-episodic details resulted in greater willingness to purchase the video game (motivational drive). These findings indicate that sharing an experience as a story can change the content and linguistic tone of memory recall, which in turn shape perceived value in naïve listeners.


Assuntos
Rememoração Mental , Narração , Humanos , Rememoração Mental/fisiologia , Feminino , Masculino , Adulto , Adulto Jovem , Jogos de Vídeo
4.
J Pharm Bioallied Sci ; 16(Suppl 2): S1281-S1286, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38882725

RESUMO

Colorectal cancer (CRC) is a pervasive malignancy that stands as a prominent contributor to global cancer-related mortality. Among the numerous causative factors, the overexpression of human epidermal growth factor receptor 2 (HER2) is notably linked to CRC progression. Acronychia (A.) pedunculata has a longstanding history in folk medicine due to its multifaceted medicinal attributes. This study aimed to assess the potential of specific bioactive compounds derived from A. pedunculata for their inhibition of HER2 in CRC, utilizing in silico analysis. The compounds were systematically evaluated through a series of computational analyses. Drug-likeness assessment, pharmacokinetic evaluation, and toxicity analysis were conducted. Molecular docking studies were performed to investigate binding affinities with the HER2 target. Additionally, bioavailability radar analysis was employed to predict oral bioavailability, while molecular target prediction provided insights into potential protein interactions. All 12 compounds demonstrated favorable drug-likeness properties and adherence to Lipinski's rule of five, indicative of the potential for good oral bioavailability. Four compounds were found to have no toxicological endpoints. Molecular docking revealed two compounds, namely caryophylla-4 (14), 8 (15)-dien-5alpha-ol and (-)-globulol, which showed promising binding affinities between several compounds and HER2. From this study, two leads were identified from A. pedunculata. Further experimental studies are required to validate the action of leads.

5.
Hippocampus ; 34(7): 327-341, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38700259

RESUMO

Recent work has identified a critical role for the hippocampus in reward-sensitive behaviors, including motivated memory, reinforcement learning, and decision-making. Animal histology and human functional neuroimaging have shown that brain regions involved in reward processing and motivation are more interconnected with the ventral/anterior hippocampus. However, direct evidence examining gradients of structural connectivity between reward regions and the hippocampus in humans is lacking. The present study used diffusion MRI (dMRI) and probabilistic tractography to quantify the structural connectivity of the hippocampus with key reward processing regions in vivo. Using a large sample of subjects (N = 628) from the human connectome dMRI data release, we found that connectivity profiles with the hippocampus varied widely between different regions of the reward circuit. While the dopaminergic midbrain (ventral tegmental area) showed stronger connectivity with the anterior versus posterior hippocampus, the ventromedial prefrontal cortex showed stronger connectivity with the posterior hippocampus. The limbic (ventral) striatum demonstrated a more homogeneous connectivity profile along the hippocampal long axis. This is the first study to generate a probabilistic atlas of the hippocampal structural connectivity with reward-related networks, which is essential to investigating how these circuits contribute to normative adaptive behavior and maladaptive behaviors in psychiatric illness. These findings describe nuanced structural connectivity that sets the foundation to better understand how the hippocampus influences reward-guided behavior in humans.


Assuntos
Conectoma , Hipocampo , Vias Neurais , Recompensa , Humanos , Hipocampo/diagnóstico por imagem , Hipocampo/fisiologia , Masculino , Feminino , Adulto , Vias Neurais/fisiologia , Vias Neurais/diagnóstico por imagem , Adulto Jovem , Imagem de Difusão por Ressonância Magnética , Área Tegmentar Ventral/diagnóstico por imagem , Área Tegmentar Ventral/fisiologia , Imagem de Tensor de Difusão , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Estriado Ventral/diagnóstico por imagem , Estriado Ventral/fisiologia
6.
Cogn Emot ; : 1-17, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38625561

RESUMO

Despite the salient experience of encoding threatening events, these memories are prone to distortions and often non-veridical from encoding to recall. Further, threat has been shown to preferentially disrupt the binding of event details and enhance goal-relevant information. While extensive work has characterised distinctive features of emotional memory, research has not fully explored the influence threat has on temporal memory, a process putatively supported by the binding of event details into a temporal context. Two primary competing hypotheses have been proposed; that threat can impair or enhance temporal memory. We analysed two datasets to assess temporal memory for an in-person haunted house experience. In study 1, we examined the temporal structure of memory by characterising memory contiguity in free recall as a function of individual levels of heart rate as a proxy of threat. In study 2, we replicated marginal findings of threat-related increases in memory contiguity found in study 1. We extended these findings by showing threat-related increases in recency discriminations, an explicit test of temporal memory. Together, these findings demonstrate that threat enhances temporal memory regarding free recall structure and during explicit memory judgments.

7.
Int J Surg ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652180

RESUMO

As one of the leading causes of global mortality and morbidity, various neurological diseases cause social and economic burdens. Despite significant advances in the treatment of neurological diseases, establishing a proper disease model, especially for degenerative and infectious diseases, remains a major challenging issue. For long, mice were the model of choice but suffered from serious drawbacks of differences in anatomical and functional aspects of the nervous system. Furthermore, the collection of post-mortem brain tissues limits their usage in cultured cell lines. Overcoming such limitations has prompted the usage of stem cells derived from the peripheral nervous system, such as the cells of the olfactory mucosa as a preferred choice. These cells can be easily cultured in vitro and retain the receptors of neuronal cells life-long. Such cells have various advantages over embryonic or induced stem cells, including homology, and ease of culture and can be conveniently obtained from diseased individuals through either biopsies or exfoliation. They have continuously helped in understanding the genetic and developmental mechanisms of degenerative diseases like Alzheimer's and Parkinson's disease. Moreover, the mode of infection of various viruses that can lead to post-viral olfactory dysfunction, such as the Zika virus can be monitored through these cells in vitro and their therapeutic development can be fastened.

8.
Proc Natl Acad Sci U S A ; 121(12): e2311077121, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38470923

RESUMO

The memory benefit that arises from distributing learning over time rather than in consecutive sessions is one of the most robust effects in cognitive psychology. While prior work has mainly focused on repeated exposures to the same information, in the real world, mnemonic content is dynamic, with some pieces of information staying stable while others vary. Thus, open questions remain about the efficacy of the spacing effect in the face of variability in the mnemonic content. Here, in two experiments, we investigated the contributions of mnemonic variability and the timescale of spacing intervals, ranging from seconds to days, to long-term memory. For item memory, both mnemonic variability and spacing intervals were beneficial for memory; however, mnemonic variability was greater at shorter spacing intervals. In contrast, for associative memory, repetition rather than mnemonic variability was beneficial for memory, and spacing benefits only emerged in the absence of mnemonic variability. These results highlight a critical role for mnemonic variability and the timescale of spacing intervals in the spacing effect, bringing this classic memory paradigm into more ecologically valid contexts.


Assuntos
Memória , Rememoração Mental , Aprendizagem , Memória de Longo Prazo , Tempo
9.
JAMA Netw Open ; 7(3): e241958, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38470416

RESUMO

Importance: COVID-19 prompted rapid development of scarce resource allocation (SRA) policies to be implemented if demand eclipsed health systems' ability to provide critical care. While SRA policies follow general ethical frameworks, understanding priorities of those affected by policies and/or tasked with implementing them is critical. Objective: To evaluate whether community members and health care profesionals (HCP) agree with SRA protocols at the University of California (UC). Design, Setting, and Participants: This survey study used social media and community-partnered engagement to recruit participants to a web-based survey open to all participants aged older than 18 years who wished to enroll. This study was fielded between May and September 2020 and queried participants' values and preferences on draft SRA policy tenets. Participants were also encouraged to forward the survey to their networks for snowball sampling. Data were analyzed from July 2020 to January 2024. Main Outcomes and Measures: Survey items assessed values and preferences, graded on Likert scales. Agreement was tabulated as difference in Likert points between expressed opinion and policy tenets. Descriptive statistics were tested for significance by HCP status. Free text responses were analyzed using applied rapid qualitative analysis. Results: A total of 1545 participants aged older than 18 years (mean [SD] age 49 [16] years; 1149 female participants [74%], 478 health care practitioners [30%]) provided data on SRA values and preferences. Agreement with UC SRA policy as drafted was moderately high among respondents, ranging from 67% to 83% across domains. Higher agreement with the interim policy was observed for laypersons across all domains except health-related factors. HCPs agreed more strongly on average that resources should not be allocated to those less likely to survive (HCP mean, 3.70; 95% CI, 3.16-3.59; vs layperson mean, 3.38; 95% CI, 3.17-3.59; P = .002), and were more in favor of reallocating life support from patients less likely to those more likely to survive (HCP mean, 6.41; 95% CI, 6.15-6.67; vs layperson mean, 5.40; 95% CI, 5.23-5.58; P < .001). Transparency and trust building themes were common in free text responses and highly rated on scaled items. Conclusions and Relevance: This survey of SRA policy values found moderate agreement with fundamental principles of such policies. Engagement with communities affected by SRA policy should continue in iterative refinement in preparation for future crises.


Assuntos
COVID-19 , Pessoal de Saúde , Humanos , Feminino , Idoso , Pessoa de Meia-Idade , COVID-19/epidemiologia , Cuidados Críticos , Instalações de Saúde , Alocação de Recursos
10.
J Cancer Res Ther ; 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38261458

RESUMO

PURPOSE: Tumor-associated serum markers have demonstrated predictive and prognostic value in patients being treated for malignancies. However, the clinical importance of tumor markers in gastric cancers (GC) is poorly standardized. OBJECTIVES: The objective is to assess the clinical utility of cytokeratin-19 fragment (CYFRA 21-1) and carcinoembryonic antigen (CEA) as serum tumor markers in advanced GC. METHODS: In this prospective study, CYFRA 21-1 and CEA levels were measured at baseline and after three cycles of chemotherapy in patients with advanced GC. The association of tumor marker levels with prognosis and decline of tumor markers with radiological overall response rates (ORR) and survival were analyzed. RESULTS: In the 105 patients, the proportion of patients with elevated baseline CYFRA 21-1 and CEA levels was 55% (N = 58) and 37% (N = 39) based on predefined cutoffs. Response assessment was done for 61 patients who received a minimum of three cycles of chemotherapy. A 15% and 13% reduction of serum levels from baseline for CYFRA 21-1 and CEA were selected for defining "CYFRA 21-1 response" and "CEA-response," respectively. Both responses were significant predictors of radiological ORR. The median overall survival (OS) was 9.6 months in the entire cohort and 13 months for patients who received at least three cycles of chemotherapy. In multivariate analysis, baseline CEA levels and ECOG status were significant predictors of OS. In a subset analysis of patients receiving palliative chemotherapy, any of the tumor marker responses predicted improved 1-year OS. CONCLUSION: In advanced GC, CYFRA 21-1 and CEA decline from baseline appeared to be reliable surrogate markers of chemotherapy efficacy and improved survival.

11.
J Cogn Neurosci ; 36(2): 362-376, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37944120

RESUMO

Most prior research characterizes information-seeking behaviors as serving utilitarian purposes, such as whether the obtained information can help solve practical problems. However, information-seeking behaviors are sensitive to different contexts (i.e., threat vs. curiosity), despite having equivalent utility. Furthermore, these search behaviors can be modulated by individuals' life history and personality traits. Yet the emphasis on utilitarian utility has precluded the development of a unified model, which explains when and how individuals actively seek information. To account for this variability and flexibility, we propose a unified information-seeking framework that examines information-seeking through the lens of motivation. This unified model accounts for integration across individuals' internal goal states and the salient features of the environment to influence information-seeking behavior. We propose that information-seeking is determined by motivation for information, invigorated either by instrumental utility or hedonic utility, wherein one's personal or environmental context moderates this relationship. Furthermore, we speculate that the final common denominator in guiding information-seeking is the engagement of different neuromodulatory circuits centered on dopaminergic and noradrenergic tone. Our framework provides a unified framework for information-seeking behaviors and generates several testable predictions for future studies.


Assuntos
Comportamento de Busca de Informação , Motivação , Humanos , Comportamento Exploratório , Dopamina
12.
J Cogn Neurosci ; 36(3): 415-434, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38060253

RESUMO

Nearly 50 years of research has focused on faces as a special visual category, especially during development. Yet it remains unclear how spatial patterns of neural similarity of faces and places relate to how information processing supports subsequent recognition of items from these categories. The current study uses representational similarity analysis and functional imaging data from 9- and 10-year-old youth during an emotional n-back task from the Adolescent Brain and Cognitive Development Study 3.0 data release to relate spatial patterns of neural similarity during working memory to subsequent out-of-scanner performance on a recognition memory task. Specifically, we examine how similarities in representations within face categories (neutral, happy, and fearful faces) and representations between visual categories (faces and places) relate to subsequent recognition memory of these visual categories. Although working memory performance was higher for faces than places, subsequent recognition memory was greater for places than faces. Representational similarity analysis revealed category-specific patterns in face-and place-sensitive brain regions (fusiform gyrus, parahippocampal gyrus) compared with a nonsensitive visual region (pericalcarine cortex). Similarity within face categories and dissimilarity between face and place categories in the parahippocampus was related to better recognition of places from the n-back task. Conversely, in the fusiform, similarity within face categories and their relative dissimilarity from places was associated with better recognition of new faces, but not old faces. These findings highlight how the representational distinctiveness of visual categories influence what information is subsequently prioritized in recognition memory during development.


Assuntos
Memória de Curto Prazo , Reconhecimento Psicológico , Adolescente , Humanos , Criança , Encéfalo , Córtex Cerebral , Emoções , Mapeamento Encefálico , Imageamento por Ressonância Magnética , Reconhecimento Visual de Modelos
13.
Proc Natl Acad Sci U S A ; 120(52): e2308593120, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38117853

RESUMO

Memory is a reconstructive process that can result in events being recalled as more positive or negative than they actually were. While positive recall biases may contribute to well-being, negative recall biases may promote internalizing symptoms, such as social anxiety. Adolescence is characterized by increased salience of peers and peak incidence of social anxiety. Symptoms often wax and wane before becoming more intractable during adulthood. Open questions remain regarding how and when biases for social feedback are expressed and how individual differences in biases may contribute to social anxiety across development. Two studies used a social feedback and cued response task to assess biases about being liked or disliked when retrieving memories vs. making predictions. Findings revealed a robust positivity bias about memories for social feedback, regardless of whether memories were true or false. Moreover, memory bias was associated with social anxiety in a developmentally sensitive way. Among adults (study 1), more severe symptoms of social anxiety were associated with a negativity bias. During the transition from adolescence to adulthood (study 2), age strengthened the positivity bias in those with less severe symptoms and strengthened the negativity bias in those with more severe symptoms. These patterns of bias were isolated to perceived memory retrieval and did not generalize to predictions about social feedback. These results provide initial support for a model by which schemas may infiltrate perceptions of memory for past, but not predictions of future, social events, shaping susceptibility for social anxiety, particularly during the transition into adulthood.


Assuntos
Ansiedade , Rememoração Mental , Adulto , Adolescente , Humanos , Retroalimentação , Memória/fisiologia , Viés
14.
Psychon Bull Rev ; 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37803231

RESUMO

Changes in context influence the way we form and structure memories. Yet, little is known about how qualitatively different types of context switches shape memory organization. The current experiments characterize how different features of context change influence the structure and organization of free recall. Participants completed a context switching paradigm in which we manipulated the rate of switches and prior experience with the contexts participants were switching between (repeated vs. novel). We measured free-recall performance and determined the extent to which participants organized items by the order in which they were encoded or the type of context with which they were originally presented. Across two experiments, we found and replicated that rapidly switching to novel, but not repeated contexts, impaired memory recall performance and biased memory towards a greater reliance on temporal information. Critically, we observed that these differences in performance may be due to distinctions in how participants organize their recalls when rapidly switching contexts. Results indicated that participants were less likely to only cluster their responses by the same context when the contexts were repeating at a high rate, as compared to when the contexts were novel. Overall, our findings support a model in which contextual familiarity rescues the costs associated with rapidly switching to new tasks or contexts.

15.
Compr Physiol ; 13(4): 5069-5076, 2023 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-37770191

RESUMO

Insulin regulates energy metabolism involving multiple organ systems. Insulin resistance (IR) occurs when organs exhibit reduced insulin sensitivity, leading to difficulties in maintaining glucose homeostasis. IR ensures decades prior to development of overt diabetes and can cause silent metabolic derangements. IR is typically seen very early in the course of chronic kidney disease (CKD) and is evident even when the estimated glomerular filtration rate (eGFR) is within the normal range and IR persists at various stages of kidney disease. In this article, we will discuss insulin handling by the kidneys, mechanisms responsible for IR in CKD, measurements and management of IR in patients with CKD, and recent type 2 diabetic trials with implications for improved cardiovascular outcomes in CKD. © 2023 American Physiological Society. Compr Physiol 13:5069-5076, 2023.


Assuntos
Resistência à Insulina , Insuficiência Renal Crônica , Humanos , Insulina , Insuficiência Renal Crônica/metabolismo , Rim/metabolismo , Progressão da Doença , Taxa de Filtração Glomerular
16.
Pain Pract ; 23(8): 914-921, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37395169

RESUMO

AIMS: Transcutaneous magnetic stimulation (TCMS) is successful in decreasing pain in several neurologic conditions. This multicenter parallel double-blind phase II clinical trial is a follow-up to a pilot study that demonstrated pain relief in patients with diabetic peripheral neuropathy (DPN) treated with TCMS. METHODS: Thirty-four participants with confirmed DPN and baseline pain score ≥ 5 were randomized to treatment at two sites. Participants were treated with either TCMS (n = 18) or sham (n = 16) applied to each foot once a week for four weeks. Pain scores using the Numeric Pain Rating Scale after 10 steps on a hard floor surface and answers to Patient-Reported Outcomes Measurement Information System pain questions were recorded by participants daily for 28 days. RESULTS: Thirty-one participants completed the study and were analyzed. Average pain scores decreased from baseline in both the groups. The difference in pain scores between TCMS and sham treatments was -0.55 for morning, -0.13 for evening, and -0.34 overall, below the pre-determined clinically relevant difference of -2. Moderate adverse events that resolved spontaneously were experienced in both treatment arms. CONCLUSION: In this two-arm trial, TCMS failed to demonstrate a significant benefit over sham in patient reported pain suggesting a substantial placebo effect in our previous pilot study. TRIAL REGISTRATION: TCMS for the Treatment of Foot Pain Caused By Diabetic Neuropathy, https://clinicaltrials.gov/ct2/show/NCT03596203, ID-NCT03596203.


Assuntos
Diabetes Mellitus , Neuropatias Diabéticas , Humanos , Neuropatias Diabéticas/tratamento farmacológico , Projetos Piloto , Dor/tratamento farmacológico , Manejo da Dor , Fenômenos Magnéticos , Método Duplo-Cego , Resultado do Tratamento
17.
J Cogn Neurosci ; 35(9): 1446-1462, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37348130

RESUMO

Systems consolidation theories posit that consolidation occurs primarily through a coordinated communication between hippocampus and neocortex [Moscovitch, M., & Gilboa, A. Systems consolidation, transformation and reorganization: Multiple trace theory, trace transformation theory and their competitors. PsyArXiv, 2021; Kumaran, D., Hassabis, D., & McClelland, J. L. What learning systems do intelligent agents need? Complementary learning systems theory updated. Trends in Cognitive Sciences, 20, 512-534, 2016; McClelland, J. L., & O'Reilly, R. C. Why there are complementary learning systems in the hippocampus and neocortex: Insights from the successes and failures of connectionist models of learning and memory. Psychological Review, 102, 419-457, 1995]. Recent sleep studies in rodents have shown that hippocampus and visual cortex replay the same information at temporal proximity ("co-replay"; Lansink, C. S., Goltstein, P. M., Lankelma, J. V., McNaughton, B. L., & Pennartz, C. M. A. Hippocampus leads ventral striatum in replay of place-reward information. PLoS Biology, 7, e1000173, 2009; Peyrache, A., Khamassi, M., Benchenane, K., Wiener, S. I., & Battaglia, F. P. Replay of rule-learning related neural patterns in the prefrontal cortex during sleep. Nature Neuroscience, 12, 919-926, 2009; Wierzynski, C. M., Lubenov, E. V., Gu, M., & Siapas, A. G. State-dependent spike-timing relationships between hippocampal and prefrontal circuits during sleep. Neuron, 61, 587-596, 2009; Ji, D., & Wilson, M. A. Coordinated memory replay in the visual cortex and hippocampus during sleep. Nature Neuroscience, 10, 100-107, 2007). We developed a novel repetition time (TR)-based co-reactivation analysis method to study hippocampal-cortical co-replays in humans using fMRI. Thirty-six young adults completed an image (face or scene) and location paired associate encoding task in the scanner, which were preceded and followed by resting state scans. We identified post-encoding rest TRs (± 1) that showed neural reactivation of each image-location trials in both hippocampus (HPC) and category-selective cortex (fusiform face area [FFA]). This allowed us to characterize temporally proximal coordinated reactivations ("co-reactivations") between HPC and FFA. Moreover, we found that increased HPC-FFA co-reactivations were associated with incorrectly recognized trials after a 1-week delay (p = .004). Finally, we found that these HPC-FFA co-reactivations were also associated with trials that were initially correctly recognized immediately after encoding but were later forgotten in 1-day (p = .043) and 1-week delay period (p = .031). We discuss these results from a trace transformation perspective [Sekeres, M. J., Winocur, G., & Moscovitch, M. The hippocampus and related neocortical structures in memory transformation. Neuroscience Letters, 680, 39-53, 2018; Winocur, G., & Moscovitch, M. Memory transformation and systems consolidation. Journal of the International Neuropsychological Society, 17, 766-780, 2011] and speculate that HPC-FFA co-reactivations may be integrating related events, at the expense of disrupting event-specific details, hence leading to forgetting.


Assuntos
Hipocampo , Vigília , Adulto Jovem , Humanos , Vigília/fisiologia , Hipocampo/fisiologia , Aprendizagem , Sono/fisiologia , Córtex Pré-Frontal/fisiologia
19.
Dev Sci ; 26(6): e13409, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37183213

RESUMO

The ongoing stream of sensory experience is so complex and ever-changing that we tend to parse this experience at "event boundaries," which structures and strengthens memory. Memory processes undergo profound change across early childhood. Whether young children also divide their ongoing processing along event boundaries, and if those boundaries relate to memory, could provide important insight into the development of memory systems. In Study 1, 4-7-year-old children and adults segmented a cartoon, and we tested their memory. Children's event boundaries were more variable than adults' and differed in location and consistency of agreement. Older children's event segmentation was more adult-like than younger children's, and children who segmented events more like adults had better memory for those events. In Study 2, we asked whether these developmental differences in event segmentation had their roots in distinct neural representations. A separate group of 4-8-year-old children watched the same cartoon while undergoing an fMRI scan. In the right hippocampus, greater pattern dissimilarity across event boundaries compared to within events was evident for both child and adult behavioral boundaries, suggesting children and adults share similar event cognition. However, the boundaries identified by a data-driven Hidden Markov Model found that a different brain region-the left and right angular gyrus-aligned only with event boundaries defined by children. Overall, these data suggest that children's event cognition is reasonably well-developed by age 4 but continues to become more adult-like across early childhood. RESEARCH HIGHLIGHTS: Adults naturally break their experience into events, which structures and strengthens memory, but less is known about children's event perception and memory. Study 1 had adults and children segment and remember events from an animated show, and Study 2 compared those segmentations to other children's fMRI data. Children show better recognition and temporal order memory and more adult-like event segmentation with age, and children who segment more like adults have better memory. Children's and adults' behavioral boundaries mapped onto pattern similarity differences in hippocampus, and children's behavioral boundaries matched a data-driven model's boundaries in angular gyrus.


Assuntos
Cognição , Memória , Adulto , Criança , Humanos , Pré-Escolar , Adolescente , Rememoração Mental , Encéfalo , Hipocampo
20.
J Exp Psychol Gen ; 152(6): 1797-1813, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36862492

RESUMO

The perception of agency can influence memory when individuals feel their decisions exert control over their environment. While perceived agency has been shown to increase memory for items, most real-life situations are much more complex. Here, we examined how an individual's agency to influence the outcome of a situation affects their ability to learn associations between items that occur prior to and after a decision is made. In our paradigm, participants were told they were playing a game show where they had to help a trial unique cue, a "contestant," choose between three doors. On "agency" trials, participants were allowed to pick any door they wanted. On "forced-choice" trials, participants were instructed to select a door that was highlighted. They then saw the outcome, a "prize" that was behind the selected door. Across multiple studies, we find evidence for agency-related memory enhancements for contestants, a pattern that extended to contestant-prize, contestant-door, and door-prize associations. Additionally, we found that agency benefits for inferred cue-outcome relationships (i.e., door-prize) were limited to situations when choices were motivated by an explicit goal. Finally, we found that agency acts indirectly to influence cue-outcome binding by enhancing processes akin to inferential reasoning which associate information across item pairs containing overlapping information. Together, these data suggest having agency over a situation leads to enhanced memory for all items in that situation. This enhanced binding for items may be occurring by the formation of causal links when an individual has agency over their learning environment. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Rememoração Mental , Motivação , Humanos , Emoções , Aprendizagem , Aprendizagem por Associação
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