Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 292
Filtrar
1.
Chemphyschem ; : e202400053, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38706399

RESUMEN

The study of fluid absorption, particularly that of water, into nanoporous materials has garnered increasing attention in the last decades across a broad range of disciplines. However, most investigation approaches to probe such behaviors are limited by characterization conditions. In this study, a combined MRI and MAS NMR method was used to study a nanoporous silica glass to acquire information about its structural framework and interactions with confined water. Specifically, MRI was used for a quantitative analysis of water extent. While MAS NMR techniques provided structural information of silicate materials, including interactive surface area and framework packing. Analysis of water spin-spin relaxation times (T2) suggested differences in water confinement within the characterized framework. Subsequent unsuccessful delivery of paramagnetic molecule into the pores enabled a quantitative assessment of the dimensions that "bottleneck" the pores. Finally, pore sizes were derived from the molecular size, density function theory (DFT) simulation and characterizations on standard samples. Our result matches with Brunauer-Emmett-Teller (BET) analysis.. The use of a paramagnetic probe for pore size determination introduces a new approach of characterization in the liquid phase, offering an alternative to the conventional BET analysis that uses gas molecule as probes.

2.
World J Gastrointest Surg ; 16(3): 842-859, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38577085

RESUMEN

BACKGROUND: Long non-coding RNAs (LncRNAs) have been found to be a potential prognostic factor for cancers, including hepatocellular carcinoma (HCC). Some LncRNAs have been confirmed as potential indicators to quantify genomic instability (GI). Nevertheless, GI-LncRNAs remain largely unexplored. This study established a GI-derived LncRNA signature (GILncSig) that can predict the prognosis of HCC patients. AIM: To establish a GILncSig that can predict the prognosis of HCC patients. METHODS: Identification of GI-LncRNAs was conducted by combining LncRNA expression and somatic mutation profiles. The GI-LncRNAs were then analyzed for functional enrichment. The GILncSig was established in the training set by Cox regression analysis, and its predictive ability was verified in the testing set and TCGA set. In addition, we explored the effects of the GILncSig and TP53 on prognosis. RESULTS: A total of 88 GI-LncRNAs were found, and functional enrichment analysis showed that their functions were mainly involved in small molecule metabolism and GI. The GILncSig was constructed by 5 LncRNAs (miR210HG, AC016735.1, AC116351.1, AC010643.1, LUCAT1). In the training set, the prognosis of high-risk patients was significantly worse than that of low-risk patients, and similar results were verified in the testing set and TCGA set. Multivariate Cox regression analysis and stratified analysis confirmed that the GILncSig could be used as an independent prognostic factor. Receiver operating characteristic curve analysis of the GILncSig showed that the area under the curve (0.773) was higher than the two LncRNA signatures published recently. Furthermore, the GILncSig may have a better predictive performance than TP53 mutation status alone. CONCLUSION: We established a GILncSig that can predict the prognosis of HCC patients, which will help to guide prognostic evaluation and treatment decisions.

3.
Ear Nose Throat J ; : 1455613241247764, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38634313

RESUMEN

Subperiosteal orbital hematoma secondary to sinusitis is rare. Thus far, 19 cases of this disease have been reported, of which none involved postoperative skin anesthesia in the region innervated by the supraorbital nerve. In this article, for the first time we report a case of subperiosteal orbital hematoma secondary to sinusitis with skin anesthesia in the area innervated by the supraorbital nerve after surgery.

4.
New Phytol ; 242(4): 1691-1703, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38659111

RESUMEN

Understanding the complex interactions between trees and fungi is crucial for forest ecosystem management, yet the influence of tree mycorrhizal types, species identity, and diversity on tree-tree interactions and their root-associated fungal communities remains poorly understood. Our study addresses this gap by investigating root-associated fungal communities of different arbuscular mycorrhizal (AM) and ectomycorrhizal (EcM) tree species pairs (TSPs) in a subtropical tree diversity experiment, spanning monospecific, two-species, and multi-species mixtures, utilizing Illumina sequencing of the ITS2 region. The study reveals that tree mycorrhizal type significantly impacts the alpha diversity of root-associated fungi in monospecific stands. Meanwhile, tree species identity's influence is modulated by overall tree diversity. Tree-related variables and spatial distance emerged as major drivers of variations in fungal community composition. Notably, in multi-species mixtures, compositional differences between root fungal communities of AM and EcM trees diminish, indicating a convergence of fungal communities irrespective of mycorrhizal type. Interestingly, dual mycorrhizal fungal communities were observed in these multi-species mixtures. This research underscores the pivotal role of mycorrhizal partnerships and the interplay of biotic and abiotic factors in shaping root fungal communities, particularly in varied tree diversity settings, and its implications for effective forest management and biodiversity conservation.


Asunto(s)
Biodiversidad , Bosques , Micobioma , Micorrizas , Raíces de Plantas , Especificidad de la Especie , Árboles , Micorrizas/fisiología , Árboles/microbiología , Raíces de Plantas/microbiología
5.
J Laryngol Otol ; 138(5): 540-547, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38348656

RESUMEN

OBJECTIVE: Retropharyngeal lymphadenectomy is challenging. This study investigated a minimally invasive approach to salvage retropharyngeal lymphadenectomy in patients with nasopharyngeal carcinoma. METHODS: An anatomical study of four fresh cadaveric heads was conducted to demonstrate the relevant details of retropharyngeal lymphadenectomy using the endoscopic transoral medial pterygomandibular fold approach. Six patients with nasopharyngeal cancer with retropharyngeal lymph node recurrence, who underwent retropharyngeal lymphadenectomy with the endoscopic transoral medial pterygomandibular fold technique at the Eye and ENT Hospital of Fudan University from July to December 2021, were included in this study. RESULTS: The anatomical study demonstrated that the endoscopic transoral medial pterygomandibular fold approach offers a short path and minimally invasive approach to the retropharyngeal space. The surgical procedure was well tolerated by all patients, with no significant post-operative complications. CONCLUSION: The endoscopic transoral medial pterygomandibular fold approach is safe and efficient for retropharyngeal lymphadenectomy.


Asunto(s)
Escisión del Ganglio Linfático , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Humanos , Escisión del Ganglio Linfático/métodos , Masculino , Neoplasias Nasofaríngeas/cirugía , Neoplasias Nasofaríngeas/patología , Carcinoma Nasofaríngeo/cirugía , Carcinoma Nasofaríngeo/patología , Femenino , Persona de Mediana Edad , Terapia Recuperativa/métodos , Cirugía Endoscópica por Orificios Naturales/métodos , Cadáver , Adulto , Faringe/cirugía , Anciano , Recurrencia Local de Neoplasia/cirugía , Recurrencia Local de Neoplasia/patología , Resultado del Tratamiento
6.
Innovation (Camb) ; 5(2): 100573, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38379792

RESUMEN

Differences in progress across sustainable development goals (SDGs) are widespread globally; meanwhile, the rising call for prioritizing specific SDGs may exacerbate such gaps. Nevertheless, how these progress differences would influence global sustainable development has been long neglected. Here, we present the first quantitative assessment of SDGs' progress differences globally by adopting the SDGs progress evenness index. Our results highlight that the uneven progress across SDGs has been a hindrance to sustainable development because (1) it is strongly associated with many public health risks (e.g., air pollution), social inequalities (e.g., gender inequality, modern slavery, wealth gap), and a reduction in life expectancy; (2) it is also associated with deforestation and habitat loss in terrestrial and marine ecosystems, increasing the challenges related to biodiversity conservation; (3) most countries with low average SDGs performance show lower progress evenness, which further hinders their fulfillment of SDGs; and (4) many countries with high average SDGs performance also showcase stagnation or even retrogression in progress evenness, which is partly ascribed to the antagonism between climate actions and other goals. These findings highlight that while setting SDGs priorities may be more realistic under the constraints of multiple global stressors, caution must be exercised to avoid new problems from intensifying uneven progress across goals. Moreover, our study reveals that the urgent needs regarding SDGs of different regions seem complementary, emphasizing that regional collaborations (e.g., demand-oriented carbon trading between SDGs poorly performed and well-performed countries) may promote sustainable development achievements at the global scale.

7.
World J Clin Cases ; 12(5): 1025-1028, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38414602

RESUMEN

BACKGROUND: A man experienced multiple episodes of macroscopic hematuria following nocturnal exercise. Urinary stones and tumors were considered the two most likely causes. The patient had two hobbies: Consuming health care products in large quantities and engaging in late-night running. CASE SUMMARY: Health care products contain a large amount of calcium phosphate, and we hypothesize that this could induce the formation of small phosphate stones. After exercise, the urinary system is abraded, resulting in bleeding. The patient was advised to stop using the health care products. Consequently, the aforementioned symptoms disappeared immediately. However, the patient resumed the above two habits one year later; correspondingly, the macroscopic hematuria reappeared. CONCLUSION: This finding further confirmed the above inference and allowed for a new avenue to determine the cause of the patient's hematuria.

8.
Bioresour Technol ; 395: 130347, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38242243

RESUMEN

The heavy metals, pesticides and dyes in agriculture and industry caused serious water pollution have increased the urgency for the advancement of biomass-based adsorbents due to their merits of low cost, high efficiency, and environmental sustainability. Thus, this review systematically examines the recent progress of lignin-based adsorbents dedicated to wastewater purification. Commencing with a succinct exposition on the intricate structure and prevalent forms of lignin, the review proceeds to expound rational design strategies tailored for lignin-based adsorbents coupled with adsorption mechanisms and regeneration methods. Emphasis is placed on the potential industrial applications of lignin-based adsorbents, accentuating their capacity for recovery and direct utilization post-use. The future challenges and outlooks associated with lignin-based adsorbents are discussed to provide novel perspectives for the development of high-performance and sustainable biosorbents, facilitating the effective removal of pollutants and the value-added utilization of resources in a sustainable manner.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , Purificación del Agua , Lignina , Colorantes , Purificación del Agua/métodos , Adsorción
9.
Insect Sci ; 2024 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-38214184

RESUMEN

The foregut, located at the front of the digestive tract, serves a vital role in insects by storing and grinding food into small particles. The innermost layer of the foregut known as the chitinous intima, comes into direct contact with the food and acts as a protective barrier against abrasive particles. Knickkopf (Knk) is required for chitin organization in the chitinous exoskeleton, tracheae and wings. Despite its significance, little is known about the biological function of Knk in the foregut. In this study, we found that LmKnk was stably expressed in the foregut, and highly expressed before molting in Locusta migratoria. To ascertain the biological function of LmKnk in the foregut, we synthesized specific double-stranded LmKnk (dsLmKnk) and injected it into locusts. Our findings showed a significant decrease in the foregut size, along with reduced food intake and accumulation of residues in the foregut after dsLmKnk injection. Morphological observations revealed that newly formed intima became thinner and lacked chitin lamella. Furthermore, fluorescence immunohistochemistry revealed that LmKnk was located in the apical region of new intima and epithelial cells. Taken together, this study provides insights into the biological function of LmKnk in the foregut, and identifies the potential target gene for exploring biological pest management strategies.

10.
Cell Death Discov ; 10(1): 32, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38228635

RESUMEN

Pyroptotic cell death, an inflammatory form of programmed cell death (PCD), is emerging as a potential therapeutic opportunity for radiotherapy (RT). RT is commonly used for cancer treatment, but its effectiveness can be limited by tumor resistance and adverse effects on healthy tissues. Pyroptosis, characterized by cell swelling, membrane rupture, and release of pro-inflammatory cytokines, has been shown to enhance the immune response against cancer cells. By inducing pyroptotic cell death in tumor cells, RT has the potential to enhance treatment outcomes by stimulating anti-tumor immune responses and improving the overall efficacy of RT. Furthermore, the release of danger signals from pyroptotic cells can promote the recruitment and activation of immune cells, leading to a systemic immune response that may target distant metastases. Although further research is needed to fully understand the mechanisms and optimize the use of pyroptotic cell death in RT, it holds promise as a novel therapeutic strategy for improving cancer treatment outcomes. This review aims to synthesize recent research on the regulatory mechanisms underlying radiation-induced pyroptosis and to elucidate the potential significance of this process in RT. The insights gained from this analysis may inform strategies to enhance the efficacy of RT for tumors.

11.
Gut Microbes ; 16(1): 2304159, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38277137

RESUMEN

Gut microbiota plays an essential role in the progression of nonalcoholic fatty liver disease (NAFLD), making the gut-liver axis a potential therapeutic strategy. Bacteroides genus, the enriched gut symbionts, has shown promise in treating fatty liver. However, further investigation is needed to identify specific beneficial Bacteroides strains for metabolic disorders in NAFLD and elucidate their underlying mechanisms. In this study, we observed a positive correlation between the abundance of Bacteroides thetaiotaomicron (B. theta) and the alleviation of metabolic syndrome in the early and end stages of NAFLD. Administration of B. theta to HFD-fed mice for 12 weeks reduced body weight and fat accumulation, decreased hyperlipidemia and insulin resistance, and prevented hepatic steatohepatitis and liver injury. Notably, B. theta did not affect these indicators in low-fat diet (LFD)-fed mice and exhibited good safety. Mechanistically, B. theta regulated gut microbial composition, characterized by a decreased Firmicutes/Bacteroidetes ratio in HFD-Fed mice. It also increased gut-liver folate levels and hepatic metabolites, alleviating metabolic dysfunction. Additionally, treatment with B. theta increased the proportion of polyunsaturated fatty acid in the mouse liver, offering a widely reported benefit for NAFLD improvement. In conclusion, this study provides evidence that B. theta ameliorates NAFLD by regulating gut microbial composition, enhancing gut-liver folate and unsaturated fatty acid metabolism, highlighting the therapeutic role of B. theta as a potential probiotic for NAFLD.


Asunto(s)
Bacteroides thetaiotaomicron , Microbioma Gastrointestinal , Enfermedad del Hígado Graso no Alcohólico , Ratones , Animales , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Dieta Alta en Grasa/efectos adversos , Hígado/metabolismo , Ratones Endogámicos C57BL
12.
Sci Total Environ ; 915: 169834, 2024 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-38190902

RESUMEN

Global climate change, particularly drought, is expected to alter grassland methane (CH4) oxidation, a key natural process against atmospheric greenhouse gas accumulation, yet the extent of this effect and its interaction with future atmospheric CH4 concentrations increases remains uncertain. To address this research gap, we measured CH4 flux during an imposed three-month rain-free period corresponding to a 100-year recurrence drought in soil mesocosms collected from 16 different Eurasian steppe sites. We also investigated the abundance and composition of methanotrophs. Additionally, we conducted a laboratory experiment to explore the impact of elevated CH4 concentration on the CH4 uptake capacity of grassland soil under drought conditions. We found that regardless of the type of grassland, CH4 flux was still being absorbed at its peak, meaning that all grasslands functioned as persistent CH4 sinks even when the soil water content (SWC) was <5 %. A bell-shaped relationship between SWC and CH4 uptake was observed in the soils. The average maximum CH4 oxidation rate in the meadow steppe was higher than that in the typical and desert steppe soils during extreme drought. The experimental elevation of atmospheric CH4 concentration counteracted the anticipated reduction in CH4 uptake related to physiological water stress on methanotrophic soil microbes under the drought stress. On the contrary, we found that across the regional scale, nitrogen, phosphorous, and total soil organic content played a crucial role in moderating the duration and magnitude of CH4 uptake with respect to SWC. USC-γ (Upland Soil Cluster γ) and JR-3 (Jasper Ridge Cluster) were the dominant group of soil methanotrophic bacteria in three types of grassland. However, the methanotrophic abundance, rather than the methanotrophic community composition, was the dominant microbiological factor governing CH4 uptake during the drought.

13.
Allergol Int ; 73(1): 115-125, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37567832

RESUMEN

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is a common chronic inflammatory disease of the nasal cavity and paranasal sinuses. The role of neutrophils in the pathogenesis of CRSwNP has attracted more attention in recent years, due to its association with more severe disease and reduced steroid responsiveness. Lipocalin-2 (LCN2) has been found to modulate neutrophils infiltration in other neutrophilic inflammation including inflammatory bowel disease, rheumatoid arthritis, and psoriasis. The aim was to evaluate the expression and regulator role of LCN2 in neutrophilic inflammation in CRSwNP, and its role as a potential biomarker predicting non-eosinophilic CRSwNP (neCRSwNP). METHODS: Bioinformatic analysis, immunostainings, real-time PCR and ELISA were used to analyze the expression and location of LCN2 in nasal tissues. The expression of proinflammatory mediators were assessed in nasal tissues and secretions. LCN2 production in human nasal epithelial cells (HNECs) and neutrophils, as well as its role in neutrophilic inflammation was evaluated by in vitro experiments. RESULTS: LCN2 was mainly located in neutrophils and HNECs of nasal polyps. LCN2 expression was also significantly higher in the polyp tissue and nasal secretions from patients with neCRSwNP. The LCN2 levels were positively correlated with type 3 inflammation markers, including G-CSF, IL-8, and IL-17. LCN2 expression could be upregulated by IL-17 A and TNF-α in HNECs, and LCN2 could also promote the expression of IL-8 in dispersed polyp cells and HNECs. CONCLUSIONS: LCN2 could serve as a novel biomarker predicting patients with neCRSwNP, and the increased expression of LCN2 may participate in the pathogenesis of neCRSwNP.


Asunto(s)
Pólipos Nasales , Rinitis , Sinusitis , Humanos , Pólipos Nasales/metabolismo , Interleucina-17/metabolismo , Rinitis/complicaciones , Sinusitis/metabolismo , Lipocalina 2/genética , Interleucina-8/metabolismo , Inflamación , Biomarcadores , Enfermedad Crónica
14.
Small ; 20(10): e2305502, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37880909

RESUMEN

Biomass-based hydrogels have attracted great attention in flexible and sustainable self-powered power sources but struggled to fabricate in a green, high-efficiency, and low-cost manner. Herein, a novel and facile alkali-polyphenol synergetic self-catalysis system is originally employed for the fast gelation of self-healable and self-adhesive lignin-based conductive hydrogels, which can be regarded as hydrogel electrodes of flexible triboelectric nanogenerators (TENGs). This synergy self-catalytic system comprises aqueous alkali and polyphenol-containing lignin, in which alkali-activated ammonium persulfate (APS) significantly accelerates the generation of radicals and initiates the polymerization of monomers, while polyphenol acts as a stabilizer to avoid bursting polymerization from inherent radical scavenging ability. Furthermore, multiple hydrogen bonds between lignin biopolymers and polyacrylamide (PAM) chains impart lignin-based hydrogels with exceptional adhesiveness and self-healing properties. Intriguingly, the alkaline conditions not only contribute to the solubility of lignin but also impart superior ionic conductivity of lignin-based hydrogel that is applicable to flexible TENG in self-powered energy-saving stair light strips, which holds great promise for industrial applications of soft electronics.

15.
16.
BMC Anesthesiol ; 23(1): 379, 2023 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-37986138

RESUMEN

BACKGROUND: Mechanical ventilation during general anesthesia may impair airway mucosal function. This study aimed to investigate the effect of pressure-controlled ventilation-volume guaranteed (PCV-VG) on bronchial mucus transport velocity (BTV) in patients during laparoscopic surgery for gynecological oncology compared with volume controlled ventilation (VCV). METHODS: 66 patients undergoing elective a laparoscopic surgery for gynecological oncology. The patients were randomized into two group receiving either PCV-VG or VCV. a drop of methylene blue was placed on the surface of the airway mucosa under the bronchoscopeand, then the distance the dye movement was measured after 2, 4, and 6 min. Outcomes were assessed at T0 (5 min after endotracheal intubation and before initiation of pneumoperitoneum), T1 and T2 (1 and 2 h after stabilization of pneumoperitoneum respectively). BTV at T0, T1 and T2 was the primary outcome. Secondary outcomes included heart rate (HR), mean arterial pressure (MAP), body temperature, end-tidal CO2 pressure (PETCO2), tidal volume(VT), peak inspiratory pressure (PIP), mean inspiratory pressure (Pmean), respiratory rate (RR), and dynamic compliance (CDyn) at T0, T1, and T2. RESULTS: 64 patients were included in the analysis. The median [interquartile range] BTV was significantly lower in VCV group at T1 and T2 that at T0 (P < 0.05). Furthermore, BTV was slightly reduced in PCV-VG compared with VCV. BTV in PCV-VG was significantly decreased at T2 compared with BTV at T0 (P < 0.05) and slightly decreased at T1 compared with T0(P > 0.05). Compared with the PCV-VG group, BTV in VCV group significantly decreased at T2 (P < 0.05). No participants experienced respiratory complications. CONCLUSIONS: PCV-VG is more suitable for patients undergoing laparoscopic surgery for gynecological oncology than VCV since it can protect mucociliary clearance function. TRIAL REGISTRATION: This trial is registered on https://www.chictr.org.cn/ in Chinese Clinical Trial Registry (ChiCTR.2200064564: Date of registration 11/10/2022).


Asunto(s)
Laparoscopía , Neumoperitoneo , Humanos , Respiración Artificial , Volumen de Ventilación Pulmonar , Moco
17.
Adv Colloid Interface Sci ; 321: 103029, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37866120

RESUMEN

Given the indispensability and immense value of rare earth elements for scientific and technological advancements in the 21st century, extracting high-quality rare earth resources from nature has become a global priority. Bastnäsite-(Ce) is one of the known rare earth minerals with high rare earth content and wide distribution, which occupies a pivotal position in human life and high-end production activities, making its efficient development and utilization crucial. In recent years, research on separating bastnäsite-(Ce) from gangue minerals has focused on the flotation process, with flotation reagents playing a critical role in achieving effective separation. This paper provides a detailed summary of current research on the behavior of bastnäsite-(Ce) flotation agents on minerals, their interaction with mineral surfaces during flotation separation, and outlines future prospects for further research.

18.
Phys Chem Chem Phys ; 25(44): 30223-30227, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37817561

RESUMEN

Polymer properties can be altered via lithium ion doping, whereby adsorbed Li+ binds with H2O within the polymer chain. However, direct spectroscopic evidence of the tightness of Li+/H2O binding in the solid state is limited, and the impact of Li+ on polymer sidechain packing is rarely reported. Here, we investigate a polystyrene/H2O/LiCl system using solid-state NMR, from which we determined a dipolar coupling of 11.4 kHz between adsorbed Li+ and H2O protons. This coupling corroborates a model whereby Li+ interacts with the oxygen atom in H2O via charge affinity, which we believe is the main driving force of Li+ binding. We demonstrated the impact of hydrated Li+ on sidechain packing and dynamics in polystyrene using proton-detected solid-state NMR. Experimental data and density functional theory (DFT) simulations revealed that the addition of Li+ and the increase in the hydration levels of Li+, coupled with aromatic ring binding, change the energy barrier of sidechain packing and dynamics and, consequently, changes the glass transition temperature of polystyrene.

19.
Cortex ; 168: 167-175, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37741132

RESUMEN

Knowing when confidence computations take place is critical for building a mechanistic understanding of the neural and computational bases of metacognition. Yet, even though a substantial amount of research has focused on revealing the neural correlates and computations underlying human confidence judgments, very little is known about the timing of confidence computations. To understand when confidence is computed, we delivered single pulses of transcranial magnetic stimulation (TMS) at different times after stimulus presentation while subjects judged the orientation of a briefly presented visual stimulus and provided a confidence rating. TMS was delivered to either the right dorsolateral prefrontal cortex (DLPFC) in the experimental group or to vertex in the control group. We found that TMS to right DLPFC, but not to vertex, led to increased confidence in the absence of changes to accuracy or metacognitive efficiency. Critically, equivalent levels of confidence increase occurred for TMS delivered between 200 and 500 msec after stimulus presentation. These results suggest that confidence computations occur during a broad window that begins before the perceptual decision has been fully made and thus provide important constraints for theories of confidence generation.

20.
Cereb Cortex ; 33(22): 11092-11101, 2023 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-37771044

RESUMEN

Research in neuroscience often assumes universal neural mechanisms, but increasing evidence points toward sizeable individual differences in brain activations. What remains unclear is the extent of the idiosyncrasy and whether different types of analyses are associated with different levels of idiosyncrasy. Here we develop a new method for addressing these questions. The method consists of computing the within-subject reliability and subject-to-group similarity of brain activations and submitting these values to a computational model that quantifies the relative strength of group- and subject-level factors. We apply this method to a perceptual decision-making task (n = 50) and find that activations related to task, reaction time, and confidence are influenced equally strongly by group- and subject-level factors. Both group- and subject-level factors are dwarfed by a noise factor, though higher levels of smoothing increases their contributions relative to noise. Overall, our method allows for the quantification of group- and subject-level factors of brain activations and thus provides a more detailed understanding of the idiosyncrasy levels in brain activations.


Asunto(s)
Encéfalo , Imagen por Resonancia Magnética , Reproducibilidad de los Resultados , Imagen por Resonancia Magnética/métodos , Encéfalo/fisiología , Mapeo Encefálico/métodos , Procesos Mentales
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...