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1.
Addict Biol ; 29(5): e13399, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38711213

RESUMEN

Excessive use of the internet, which is a typical scenario of self-control failure, could lead to potential consequences such as anxiety, depression, and diminished academic performance. However, the underlying neuropsychological mechanisms remain poorly understood. This study aims to investigate the structural basis of self-control and internet addiction. In a cohort of 96 internet gamers, we examined the relationships among grey matter volume and white matter integrity within the frontostriatal circuits and internet addiction severity, as well as self-control measures. The results showed a significant and negative correlation between dACC grey matter volume and internet addiction severity (p < 0.001), but not with self-control. Subsequent tractography from the dACC to the bilateral ventral striatum (VS) was conducted. The fractional anisotropy (FA) and radial diffusivity of dACC-right VS pathway was negatively (p = 0.011) and positively (p = 0.020) correlated with internet addiction severity, respectively, and the FA was also positively correlated with self-control (p = 0.036). These associations were not observed for the dACC-left VS pathway. Further mediation analysis demonstrated a significant complete mediation effect of self-control on the relationship between FA of the dACC-right VS pathway and internet addiction severity. Our findings suggest that the dACC-right VS pathway is a critical neural substrate for both internet addiction and self-control. Deficits in this pathway may lead to impaired self-regulation over internet usage, exacerbating the severity of internet addiction.


Asunto(s)
Imagen de Difusión Tensora , Sustancia Gris , Trastorno de Adicción a Internet , Autocontrol , Sustancia Blanca , Humanos , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Masculino , Trastorno de Adicción a Internet/diagnóstico por imagen , Trastorno de Adicción a Internet/fisiopatología , Femenino , Imagen de Difusión Tensora/métodos , Adulto , Adulto Joven , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Estriado Ventral/diagnóstico por imagen , Estriado Ventral/fisiopatología , Estriado Ventral/patología , Índice de Severidad de la Enfermedad , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/fisiopatología , Cuerpo Estriado/diagnóstico por imagen , Cuerpo Estriado/patología , Cuerpo Estriado/fisiopatología , Internet , Lóbulo Frontal/diagnóstico por imagen , Lóbulo Frontal/patología , Lóbulo Frontal/fisiopatología
2.
Cereb Cortex ; 33(6): 2774-2787, 2023 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-35671498

RESUMEN

Working memory (WM) is essential for cognition, but the underlying neural mechanisms remain elusive. From a hierarchical processing perspective, this paper proposed and tested a hypothesis that a domain-general network at the top of the WM hierarchy can interact with distinct domain-preferential intermediate circuits to support WM. Employing a novel N-back task, we first identified the posterior superior temporal gyrus (pSTG), middle temporal area (MT), and postcentral gyrus (PoCG) as intermediate regions for biological motion and shape motion processing, respectively. Using further psychophysiological interaction analyses, we delineated a frontal-parietal network (FPN) as the domain-general network. These results were further verified and extended by a delayed match to sample (DMS) task. Although the WM load-dependent and stimulus-free activations during the DMS delay phase confirm the role of FPN as a domain-general network to maintain information, the stimulus-dependent activations within this network during the DMS encoding phase suggest its involvement in the final stage of the hierarchical processing chains. In contrast, the load-dependent activations of intermediate regions in the N-back task highlight their further roles beyond perception in WM tasks. These results provide empirical evidence for a hierarchical processing model of WM and may have significant implications for WM training.


Asunto(s)
Cognición , Memoria a Corto Plazo , Lóbulo Frontal/diagnóstico por imagen , Cognición/fisiología , Humanos , Masculino , Femenino , Adulto , Imagen por Resonancia Magnética
3.
Addict Biol ; 27(5): e13210, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36001435

RESUMEN

Self-control is important for long-term success and could be a protective factor against maladaptive behaviours such as excessive gaming activity or Internet gaming disorder (IGD). However, the neurobiological basis of self-control and its relationship to IGD remain elusive. Using resting-state fMRI data from 89 participants aged from 18 to 26, we found that self-control and the number of IGD symptoms (IGD-S) were positively and negatively correlated with functional connectivity between right ventral striatum (rVS) and dorsal anterior cingulate cortex (dACC), respectively. A mediation analysis indicated that self-control influenced IGD-S partially through the rVS-dACC connectivity. In addition, step-wise regression analyses revealed that the rVS connectivity in a reward-anticipation limbic pathway contributed to IGD-S but not self-control, independent of the dACC pathway. These results suggest that the cingulate-ventral striatal functional connectivity may serve as an important neurobiological underpinning of self-control to regulate maladaptive behaviours such as these manifesting IGD through striatal circuitry balance.


Asunto(s)
Conducta Adictiva , Estriado Ventral , Juegos de Video , Humanos , Conducta Adictiva/diagnóstico por imagen , Encéfalo , Mapeo Encefálico/métodos , Giro del Cíngulo/diagnóstico por imagen , Internet , Trastorno de Adicción a Internet , Imagen por Resonancia Magnética , Vías Nerviosas/diagnóstico por imagen , Estriado Ventral/diagnóstico por imagen
4.
Neuroimage ; 237: 118136, 2021 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-33951514

RESUMEN

Cutting-edge recommendation algorithms have been widely used by media platforms to suggest users with personalized content. While such user-specific recommendations may satisfy users' needs to obtain intended information, some users may develop a problematic use pattern manifested by addiction-like undesired behaviors. Using a popular video sharing and recommending platform (TikTok) as an example, the present study first characterized use-related undesired behaviors with a questionnaire, then investigated how personally recommended videos modulated brain activity with an fMRI experiment. We found more undesired symptoms were related to lower self-control ability among young adults, and about 5.9% of TikTok users may have significant problematic use. The fMRI results showed higher brain activations in sub-components of the default mode network (DMN), ventral tegmental area, and discrete regions including lateral prefrontal, anterior thalamus, and cerebellum when viewing personalized videos in contrast to non-personalized ones. Psychophysiological interaction analyses revealed stronger coupling between activated DMN subregions and neural pathways underlying auditory and visual processing, as well as the frontoparietal network. This study highlights the functional heterogeneity of DMN in viewing personalized videos and may shed light on the neural underpinnings of how recommendation algorithms are able to keep the user's attention to suggested contents.


Asunto(s)
Corteza Cerebral/fisiología , Red en Modo Predeterminado/fisiología , Trastorno de Adicción a Internet/fisiopatología , Autocontrol , Medios de Comunicación Sociales , Área Tegmental Ventral/fisiología , Grabación en Video , Adulto , Corteza Cerebral/diagnóstico por imagen , Red en Modo Predeterminado/diagnóstico por imagen , Femenino , Humanos , Trastorno de Adicción a Internet/diagnóstico por imagen , Imagen por Resonancia Magnética , Masculino , Área Tegmental Ventral/diagnóstico por imagen , Adulto Joven
5.
ACS Appl Mater Interfaces ; 12(16): 19023-19032, 2020 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-32233448

RESUMEN

Si-based electrodes offer exceptionally high capacity and energy density for lithium-ion batteries (LIBs),but suffer from poor structural stability and electrical conductivity that hamper their practical applications. To tackle these obstacles, we design a C/polymer bilayer coating deposited on Si-SiOx microparticles. The inner C coating is used to improve electrical conductivity. The outer C-nanoparticle-reinforced polypyrrole (CNP-PPy) is a polymer matrix composite that can minimize the volumetric expansion of Si-SiOx and enhance its structural stability during battery operation. Electrodes made of such robust Si-SiOx@C/CNP-PPy microparticles exhibit excellent cycling performance: 83% capacity retention (794 mAh g-1) at a 2 C rate after more than 900 cycles for a coin-type half cell, and 80% capacity retention (with initial energy density of 308 Wh kg-1) after over 1100 cycles for a pouch-type full cell. By comparing the samples with different coatings, an in-depth understanding of the performance enhancement is achieved, i.e., the C/CNP-PPy with cross-link bondings formed in the bilayer coating plays a key role for the improved structural stability. Moreover, a full battery using the Si-SiOx@C/CNP-PPy electrode successfully drives a car model, demonstrating a bright application prospect of the C/polymer bilayer coating strategy to make future commercial LIBs with high stability and energy density.

6.
Front Chem ; 8: 62, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32175304

RESUMEN

A facile hydrothermal approach was adopted to the direct synthesis of bimetallic sulfide (CuCo2S4) on carbon cloth (CC) without binders for the supercapacitor's electrodes. A possible formation mechanism was proposed. The prepared bimetallic electrode exhibited a high specific capacitance (Csp) of 1,312 F·g-1 at 1 A·g-1, and an excellent capacitance retention of 94% at 5 A·g-1 over 5,000 cycles. In addition, the asymmetric supercapacitor (CuCo2S4/CC//AC/CC) exhibited energy density (42.9 wh·kg-1 at 0.8 kW·kg-1) and outstanding cycle performance (80% initial capacity retention after 5,000 cycles at 10 A·g-1). It should be noted that the electrochemical performance of a supercapacitor device is quite stable at different bending angles. Two charged devices in series can light 28 red-colored LEDs (2.0 V) for 5 min. All of this serves to indicate the potentially high application value of CuCo2S4.

7.
Phys Chem Chem Phys ; 16(2): 681-4, 2014 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-24276234

RESUMEN

By combining two pseudocapacitance charge-storage mechanisms occurring on the electrode and in the electrolyte, respectively, the specific capacitance of NiO at -20 °C in an alkaline electrolyte containing Fe(CN)6(3-)/Fe(CN)6(4-) couple increases twice, superior to the level at room temperature.

8.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 3): o662, 2011 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-21522413

RESUMEN

In the title compound, C(16)H(17)ClN(4)O(2), the aromatic ring is twisted slightly with respect to the plane of the diazene group [N-N-C-C torsion angle = -3.9 (4)°]. The NO(2) group is twisted by 16.2 (4)° relative to the aromatic ring. The two ethyl chains are positioned such that one ethyl chain lies above and the other below the ring.

9.
Huan Jing Ke Xue ; 27(5): 862-8, 2006 May.
Artículo en Chino | MEDLINE | ID: mdl-16850823

RESUMEN

The growth-inhibiting effects of Gemini1231 surfactant on Prorocentrum donghaiense, Alexandrium tamarense, Gymnodinium sp., Heterosigma akashiwo, Skeletonema costatum , Platymonas helgolanidica and Platymonas subcordiforus were investigated. The results demonstrate that the growth of P. donghaiense, A. tamarense and H. akashiwo was strongly inhibited in medium containing Gemini1231 from 0.2 to 0.5 mg x L(-1), and the S. costatum was also inhibited at concentrations above 0.5 mg x L(-1). However, the effects of this surfactant on the growth of Gymnodinium sp. and two beneficial green microalgae tested were negligible under the same treatment, indicating the potential for the selective control of red tide organisms. In addition, the analysis of the correlation between the inhibitory effect of the Gemini1231 on the algae tested and fatty acid composition of the algae implied that the differences in the fatty acid composition, especially the proportion of PUFAs, were responsible for the species-specific responses to biquaternary ammonium salt.


Asunto(s)
Calcitriol/análogos & derivados , Eucariontes/efectos de los fármacos , Eutrofización/efectos de los fármacos , Compuestos de Amonio Cuaternario/farmacología , Calcitriol/farmacología , Eucariontes/crecimiento & desarrollo
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