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1.
Neuroimage Clin ; 26: 102202, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32045732

RESUMO

Current models of addiction biology highlight altered neural responses to non-drug rewards as a central feature of addiction. However, given that drugs of abuse can directly impact reward-related dopamine circuitry, it is difficult to determine the extent to which reward processing alterations are a trait feature of individuals with addictions, or primarily a consequence of exogenous drug exposure. Examining individuals with behavioral addictions is one promising approach for disentangling neural features of addiction from the direct effects of substance exposure. The current fMRI study compared neural responses during monetary reward processing between drug naïve young adults with a behavioral addiction, internet gaming disorder (IGD; n = 22), and healthy controls (n = 27) using a monetary incentive delay task. Relative to controls, individuals with IGD exhibited blunted caudate activity associated with loss magnitude at the outcome stage, but did not differ from controls in neural activity at other stages. These findings suggest that decreased loss sensitivity might be a critical feature of IGD, whereas alterations in gain processing may be less characteristic of individuals with IGD, relative to those with substance use disorders. Therefore, classic theories of altered reward processing in substance use disorders should be translated to behavioral addictions with caution.

2.
Neurosci Biobehav Rev ; 105: 288-304, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31319124

RESUMO

Many studies have reported that heavy substance use is associated with impaired response inhibition. Studies typically focused on associations with a single substance, while polysubstance use is common. Further, most studies compared heavy users with light/non-users, though substance use occurs along a continuum. The current mega-analysis accounted for these issues by aggregating individual data from 43 studies (3610 adult participants) that used the Go/No-Go (GNG) or Stop-signal task (SST) to assess inhibition among mostly "recreational" substance users (i.e., the rate of substance use disorders was low). Main and interaction effects of substance use, demographics, and task-characteristics were entered in a linear mixed model. Contrary to many studies and reviews in the field, we found that only lifetime cannabis use was associated with impaired response inhibition in the SST. An interaction effect was also observed: the relationship between tobacco use and response inhibition (in the SST) differed between cannabis users and non-users, with a negative association between tobacco use and inhibition in the cannabis non-users. In addition, participants' age, education level, and some task characteristics influenced inhibition outcomes. Overall, we found limited support for impaired inhibition among substance users when controlling for demographics and task-characteristics.

3.
Sci Rep ; 9(1): 10048, 2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31296887

RESUMO

We present a two-dimensional (2D) parity-time-symmetric (PT-symmetry) phononic crystals (PCs) with balanced gain and loss medium. Using the super cell method of rectangular lattice, we exhibit the thresholdless spontaneous PT-symmetry breaking in the band structure. The numerical results show that the asymmetric scattering properties obviously occur in a non-Hermitian system. At two specific incident frequencies, unidirectional reflectionless and perfect transmission behaviors exist individually in opposite directions, which are accompanied by a phase transition of π. Based on the generalized Snell's law, combining such a PT-symmetric medium, we design a novel metamaterial crystal for PT-symmetric acoustic flat focusing. Its focus frequency can also be modulated by the gain/loss parameter. The novel flat focusing based on the PT-symmetry that we propose opens a new door for high-dimensional applications of non-Hermitian metamaterials in acoustic wave manipulation.

4.
J Behav Addict ; 8(2): 277-287, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31146550

RESUMO

BACKGROUND: Cue-induced brain reactivity has been suggested to be a fundamental and important mechanism explaining the development, maintenance, and relapse of addiction, including Internet gaming disorder (IGD). Altered activity in addiction-related brain regions has been found during cue-reactivity in IGD using functional magnetic resonance imaging (fMRI), but less is known regarding the alterations of coordinated whole brain activity patterns in IGD. METHODS: To investigate the activity of temporally coherent, large-scale functional brain networks (FNs) during cue-reactivity in IGD, independent component analysis was applied to fMRI data from 29 male subjects with IGD and 23 matched healthy controls (HC) performing a cue-reactivity task involving Internet gaming stimuli (i.e., game cues) and general Internet surfing-related stimuli (i.e., control cues). RESULTS: Four FNs were identified that were related to the response to game cues relative to control cues and that showed altered engagement/disengagement in IGD compared with HC. These FNs included temporo-occipital and temporo-insula networks associated with sensory processing, a frontoparietal network involved in memory and executive functioning, and a dorsal-limbic network implicated in reward and motivation processing. Within IGD, game versus control engagement of the temporo-occipital and frontoparietal networks were positively correlated with IGD severity. Similarly, disengagement of temporo-insula network was negatively correlated with higher game-craving. DISCUSSION: These findings are consistent with altered cue-reactivity brain regions reported in substance-related addictions, providing evidence that IGD may represent a type of addiction. The identification of the networks might shed light on the mechanisms of the cue-induced craving and addictive Internet gaming behaviors.


Assuntos
Comportamento Aditivo/fisiopatologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Sinais (Psicologia) , Imagem por Ressonância Magnética/métodos , Jogos de Vídeo/psicologia , Adulto , Comportamento Aditivo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Humanos , Internet , Masculino , Adulto Jovem
5.
Front Psychiatry ; 9: 154, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29740358

RESUMO

Internet gaming disorder (IGD) is characterized by cognitive and emotional deficits. Previous studies have reported the co-occurrence of IGD and depression. However, extant brain imaging research has largely focused on cognitive deficits in IGD. Few studies have addressed the comorbidity between IGD and depression symptoms and underlying neural mechanisms. Here, we systematically investigated this issue by combining a longitudinal survey study, a cross-sectional resting-state functional connectivity (rsFC) study and an intervention study. Autoregressive cross-lagged modeling on a longitudinal dataset of college students showed that IGD severity and depression are reciprocally predictive. At the neural level, individuals with IGD exhibited enhanced rsFC between the left amygdala and right dorsolateral prefrontal cortex (DLPFC), inferior frontal and precentral gyrus, compared with control participants, and the amygdala-frontoparietal connectivity at the baseline negatively predicted reduction in depression symptoms following a psychotherapy intervention. Further, following the intervention, individuals with IGD showed decreased connectivity between the left amygdala and left middle frontal and precentral gyrus, as compared with the non-intervention group. These findings together suggest that IGD may be closely associated with depression; aberrant rsFC between emotion and executive control networks may underlie depression and represent a therapeutic target in individuals with IGD. Registry name: The behavioral and brain mechanism of IGD; URL: https://www.clinicaltrials.gov/ct2/show/NCT02550405; Registration number: NCT02550405.

6.
Psychol Addict Behav ; 32(3): 365-372, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29771562

RESUMO

Internet addiction has been typically conceptualized as either a continuous construct or a dichotomous construct. Limited research has differentiated adolescents with problematic Internet use (PIU) from the Internet addiction group (IA) and/or nonproblematic Internet use group (NPIU) and examined the potential correlates. To fill this gap, based on data obtained from 956 Chinese adolescents (11-19 years, 47% male), this study examined if adolescents with PIU is a distinctive group from the IA and NPIU. This study also examined factors from different ecological levels that may differentiate among the three groups, including individual, parental, peer, and sociodemographic factors. Results indicated that IA, PIU, and NPIU differed significantly on scores of Young's Diagnostic Questionnaire (YDQ). Critical factors emerging from different ecological levels could differentiate between PIU and NPIU and between IA and NPIU. Such findings suggest that PIU may represent a distinct, intermediate group of Internet users. The potential theoretical and practical implications of identifying PIU were also discussed. (PsycINFO Database Record


Assuntos
Comportamento do Adolescente/psicologia , Comportamento Aditivo/diagnóstico , Internet , Pais , Grupo Associado , Adolescente , Comportamento Aditivo/psicologia , Criança , China , Estudos Transversais , Feminino , Humanos , Estudos Longitudinais , Masculino , Relações Pais-Filho , Inquéritos e Questionários , Adulto Jovem
7.
Addict Biol ; 23(1): 337-346, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-27894158

RESUMO

Psychobehavioral intervention is an effective treatment of Internet addiction, including Internet gaming disorder (IGD). However, the neural mechanisms underlying its efficacy remain unclear. Cortical-ventral striatum (VS) circuitry is a common target of psychobehavioral interventions in drug addiction, and cortical-VS dysfunction has been reported in IGD; hence, the primary aim of the study was to investigate how the VS circuitry responds to psychobehavioral interventions in IGD. In a cross-sectional study, we examined resting-state functional connectivity of the VS in 74 IGD subjects (IGDs) and 41 healthy controls (HCs). In a follow-up craving behavioral intervention (CBI) study, of the 74 IGD subjects, 20 IGD subjects received CBI (CBI+) and 16 IGD subjects did not (CBI-). All participants were scanned twice with similar time interval to assess the effects of CBI. IGD subjects showed greater resting-state functional connectivity of the VS to left inferior parietal lobule (lIPL), right inferior frontal gyrus and left middle frontal gyrus, in positive association with the severity of IGD. Moreover, compared with CBI-, CBI+ showed significantly greater decrease in VS-lIPL connectivity, along with amelioration in addiction severity following the intervention. These findings demonstrated that functional connectivity between VS and lIPL, each presumably mediating gaming craving and attentional bias, may be a potential biomarker of the efficacy of psychobehavioral intervention. These results also suggested that non-invasive techniques such as transcranial magnetic or direct current stimulation targeting the VS-IPL circuitry may be used in the treatment of Internet gaming disorders.


Assuntos
Terapia Comportamental , Comportamento Aditivo/reabilitação , Córtex Cerebral/diagnóstico por imagem , Fissura , Internet , Estriado Ventral/diagnóstico por imagem , Jogos de Vídeo , Comportamento Aditivo/diagnóstico por imagem , Comportamento Aditivo/fisiopatologia , Estudos de Casos e Controles , Córtex Cerebral/fisiopatologia , Estudos Transversais , Neuroimagem Funcional , Humanos , Imagem por Ressonância Magnética , Masculino , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Estriado Ventral/fisiopatologia , Adulto Jovem
8.
Neuropsychopharmacology ; 43(6): 1364-1372, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29154365

RESUMO

Difficulties in emotion regulation are commonly reported among individuals with alcohol and drug addictions and contribute to the acquisition and maintenance of addictive behaviors. Alterations in neural processing of negative affective stimuli have further been demonstrated among individuals with addictions. However, it is unclear whether these alterations are a general feature of addictions or are a result of prolonged exposure to drugs of abuse. To test the hypothesis of altered negative affect processing independent of drug effects, this study assessed neural function among drug-naïve youth with a behavioral addiction-Internet gaming disorder (IGD). Fifty-six young adults (28 with IGD, 28 matched controls) participated in fMRI scanning during performance of a well-validated emotion regulation task. Between-group differences in neural activity during task performance were assessed using a whole-brain, mixed-effects ANOVA with correction for multiple comparisons at currently recommended thresholds (voxel-level p<0.001, pFWE<0.05). Compared to controls, youth with IGD exhibited significantly blunted neural responses within distributed subcortical and cortical regions including the striatum, insula, lateral prefrontal cortex and anterior cingulate in response to negative affective cues, as well as during emotion regulation. Independent component analysis (ICA) further identified between-group differences in engagement of a fronto-cingulo-parietal network, involving decreased engagement in IGD youth relative to controls. Study findings are largely consistent with those from prior neuroimaging studies in substance-use disorders, thus raising the possibility that neural processing of negative affect may be blunted across drug and behavioral addictions independent of acute or chronic drug effects.


Assuntos
Comportamento Aditivo/fisiopatologia , Encéfalo/fisiopatologia , Emoções/fisiologia , Jogo de Azar/fisiopatologia , Internet , Adolescente , Adulto , Comportamento Aditivo/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Inteligência Emocional/fisiologia , Jogo de Azar/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética , Masculino , Adulto Jovem
9.
Neurosci Biobehav Rev ; 83: 313-324, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29102686

RESUMO

This meta-analytic study aimed to identify the common and specific neural alterations in Internet gaming disorder (IGD) across different domains and modalities. Two separate meta-analyses for functional neural activation and gray-matter volume were conducted. Sub-meta-analyses for the domains of reward, cold-executive, and hot-executive functions were also performed, respectively. IGD subjects, compared with healthy controls, showed: (1) hyperactivation in the anterior and posterior cingulate cortices, caudate, posterior inferior frontal gyrus (IFG), which were mainly associated with studies measuring reward and cold-executive functions; and, (2) hypoactivation in the anterior IFG in relation to hot-executive function, the posterior insula, somatomotor and somatosensory cortices in relation to reward function. Furthermore, IGD subjects showed reduced gray-matter volume in the anterior cingulate, orbitofrontal, dorsolateral prefrontal, and premotor cortices. These findings suggest that IGD is associated with both functional and structural neural alterations in fronto-striatal and fronto-cingulate regions. Moreover, multi-domain assessments capture different aspects of neural alterations in IGD, which may be helpful for developing effective interventions targeting specific functions.


Assuntos
Mapeamento Encefálico , Encéfalo/patologia , Encéfalo/fisiopatologia , Jogo de Azar/patologia , Internet , Encéfalo/diagnóstico por imagem , Função Executiva , Feminino , Jogo de Azar/diagnóstico por imagem , Humanos , Masculino , Neuroimagem
11.
Neuroimage Clin ; 14: 741-749, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28413776

RESUMO

Risk-taking is purported to be central to addictive behaviors. However, for Internet gaming disorder (IGD), a condition conceptualized as a behavioral addiction, the neural processes underlying impaired decision-making (risk evaluation and outcome processing) related to gains and losses have not been systematically investigated. Forty-one males with IGD and 27 healthy comparison (HC) male participants were recruited, and the cups task was used to identify neural processes associated with gain- and loss-related risk- and outcome-processing in IGD. During risk evaluation, the IGD group, compared to the HC participants, showed weaker modulation for experienced risk within the bilateral dorsolateral prefrontal cortex (DLPFC) (t = - 4.07; t = - 3.94; PFWE  < 0.05) and inferior parietal lobule (IPL) (t = - 4.08; t = - 4.08; PFWE  < 0.05) for potential losses. The modulation of the left DLPFC and bilateral IPL activation were negatively related to addiction severity within the IGD group (r = - 0.55; r = - 0.61; r = - 0.51; PFWE  < 0.05). During outcome processing, the IGD group presented greater responses for the experienced reward within the ventral striatum, ventromedial prefrontal cortex, and orbitofrontal cortex (OFC) (t = 5.04, PFWE  < 0.05) for potential gains, as compared to HC participants. Within the IGD group, the increased reward-related activity in the right OFC was positively associated with severity of IGD (r = 0.51, PFWE  < 0.05). These results provide a neurobiological foundation for decision-making deficits in individuals with IGD and suggest an imbalance between hypersensitivity for reward and weaker risk experience and self-control for loss. The findings suggest a biological mechanism for why individuals with IGD may persist in game-seeking behavior despite negative consequences, and treatment development strategies may focus on targeting these neural pathways in this population.


Assuntos
Mapeamento Encefálico , Tomada de Decisões/fisiologia , Jogo de Azar/diagnóstico por imagem , Jogo de Azar/fisiopatologia , Internet , Assunção de Riscos , Adolescente , Adulto , Análise de Variância , Encéfalo/diagnóstico por imagem , Distribuição de Qui-Quadrado , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imagem por Ressonância Magnética , Masculino , Oxigênio/sangue , Inquéritos e Questionários , Adulto Jovem
12.
Addict Biol ; 22(3): 791-801, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-26732520

RESUMO

Studies conducted in drug addiction suggest a transition in processing of drug-related cues from the ventral to the dorsal component of the striatum. However, this process has not been studied in a behavioral addiction. Assessment of this process in a non-drug addiction can provide insight into the pathophysiology of both substance and behavioral addictions. Thirty-nine male Internet gaming disorder (IGD) subjects and 23 male matched healthy controls (HCs) participated in functional magnetic resonance imaging during performance of a cue-reactivity task involving alternating presentation of Internet gaming-related stimuli (game cues) and general Internet surfing-related stimuli (control cues). Cue-induced neural activations in the ventral and dorsal striatum (DS) were compared between IGD and HC participants. Associations between cue-reactivity within these regions and cue-induced craving and severity and duration of IGD were also explored. IGD participants exhibited higher cue-induced activations within both the ventral and DS when compared with HCs. Within the IGD group, activity within the left ventral striatum (VS) was correlated negatively with cue-induced craving; positive associations were found between activations within the DS (right putamen, pallidum and left caudate) and duration of IGD. Cue-induced activity within the left putamen was negatively associated with right VS volumes among IGD participants. Consistent with studies in substance addictions, our results suggest that a transition from ventral to dorsal striatal processing may occur among individuals with IGD, a condition without the impact of substance intake.


Assuntos
Comportamento Aditivo/fisiopatologia , Corpo Estriado/fisiopatologia , Sinais (Psicologia) , Internet , Jogos de Vídeo , Adulto , Corpo Estriado/diagnóstico por imagem , Humanos , Masculino , Estriado Ventral/diagnóstico por imagem , Estriado Ventral/fisiopatologia , Adulto Jovem
13.
Neuroimage Clin ; 12: 591-599, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27699148

RESUMO

Internet gaming disorder (IGD) is characterized by high levels of craving for online gaming and related cues. Since addiction-related cues can evoke increased activation in brain areas involved in motivational and reward processing and may engender gaming behaviors or trigger relapse, ameliorating cue-induced craving may be a promising target for interventions for IGD. This study compared neural activation between 40 IGD and 19 healthy control (HC) subjects during an Internet-gaming cue-reactivity task and found that IGD subjects showed stronger activation in multiple brain areas, including the dorsal striatum, brainstem, substantia nigra, and anterior cingulate cortex, but lower activation in the posterior insula. Furthermore, twenty-three IGD subjects (CBI + group) participated in a craving behavioral intervention (CBI) group therapy, whereas the remaining 17 IGD subjects (CBI - group) did not receive any intervention, and all IGD subjects were scanned during similar time intervals. The CBI + group showed decreased IGD severity and cue-induced craving, enhanced activation in the anterior insula and decreased insular connectivity with the lingual gyrus and precuneus after receiving CBI. These findings suggest that CBI is effective in reducing craving and severity in IGD, and it may exert its effects by altering insula activation and its connectivity with regions involved in visual processing and attention bias.


Assuntos
Comportamento Aditivo/fisiopatologia , Tronco Encefálico/fisiopatologia , Córtex Cerebral/fisiopatologia , Fissura/fisiologia , Sinais (Psicologia) , Internet , Neostriado/fisiopatologia , Jogos de Vídeo/psicologia , Adulto , Comportamento Aditivo/diagnóstico por imagem , Tronco Encefálico/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Feminino , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/fisiopatologia , Humanos , Imagem por Ressonância Magnética , Masculino , Neostriado/diagnóstico por imagem , Substância Negra/diagnóstico por imagem , Substância Negra/fisiopatologia , Adulto Jovem
14.
Sci Rep ; 6: 28109, 2016 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-27381822

RESUMO

Internet gaming disorder (IGD) has become a serious mental health issue worldwide. Evaluating the benefits of interventions for IGD is of great significance. Thirty-six young adults with IGD and 19 healthy comparison (HC) subjects were recruited and underwent resting-state fMRI scanning. Twenty IGD subjects participated in a group craving behavioral intervention (CBI) and were scanned before and after the intervention. The remaining 16 IGD subjects did not receive an intervention. The results showed that IGD subjects showed decreased amplitude of low fluctuation in the orbital frontal cortex and posterior cingulate cortex, and exhibited increased resting-state functional connectivity between the posterior cingulate cortex and dorsolateral prefrontal cortex, compared with HC subjects. Compared with IGD subjects who did not receive the intervention, those receiving CBI demonstrated significantly reduced resting-state functional connectivity between the: (1) orbital frontal cortex with hippocampus/parahippocampal gyrus; and, (2) posterior cingulate cortex with supplementary motor area, precentral gyrus, and postcentral gyrus. These findings suggest that IGD is associated with abnormal resting-state neural activity in reward-related, default mode and executive control networks. Thus, the CBI may exert effects by reducing interactions between regions within a reward-related network, and across the default mode and executive control networks.


Assuntos
Comportamento Aditivo/fisiopatologia , Mapeamento Encefálico/métodos , Fissura/fisiologia , Lobo Frontal/fisiopatologia , Giro do Cíngulo/fisiopatologia , Comportamento Aditivo/psicologia , Estudos de Casos e Controles , Feminino , Humanos , Internet , Imagem por Ressonância Magnética/métodos , Masculino , Jogos de Vídeo/psicologia , Adulto Jovem
15.
Addict Biol ; 21(3): 743-51, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-25899520

RESUMO

The insula has been implicated in salience processing, craving, and interoception, all of which are critical to the clinical manifestations of drug and behavioral addiction. In this functional magnetic resonance imaging (fMRI) study, we examined resting-state functional connectivity (rsFC) of the insula and its association with Internet gaming characteristics in 74 young adults with Internet gaming disorder (IGD) and 41 age- and gender-matched healthy control subjects (HCs). In comparison with HCs, IGD subjects (IGDs) exhibited enhanced rsFC between the anterior insula and a network of regions including anterior cingulate cortex (ACC), putamen, angular gyrus, and precuneous, which are involved in salience, craving, self-monitoring, and attention. IGDs also demonstrated significantly stronger rsFC between the posterior insula and postcentral gyrus, precentral gyrus, supplemental motor area, and superior temporal gyrus (STG), which are involved in interoception, movement control, and auditory processing. Furthermore, IGD severity was positively associated with connectivity between the anterior insula and angular gyrus, and STG, and with connectivity between the posterior insula and STG. Duration of Internet gaming was positively associated with connectivity between the anterior insula and ACC. These findings highlight a key role of the insula in manifestation of the core symptoms of IGD and the importance to examine functional abnormalities of the anterior and posterior insula separately in IGDs.


Assuntos
Comportamento Aditivo/fisiopatologia , Encéfalo/fisiopatologia , Internet , Jogos de Vídeo , Adulto , Comportamento Aditivo/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Estudos de Casos e Controles , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiopatologia , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/fisiopatologia , Neuroimagem Funcional , Humanos , Imagem por Ressonância Magnética , Masculino , Córtex Motor/diagnóstico por imagem , Córtex Motor/fisiopatologia , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/fisiopatologia , Índice de Gravidade de Doença , Córtex Somatossensorial/diagnóstico por imagem , Córtex Somatossensorial/fisiopatologia , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiopatologia , Fatores de Tempo , Adulto Jovem
16.
Psychiatry Res ; 229(1-2): 302-9, 2015 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-26168928

RESUMO

A growing body of evidence indicates that both inhibition and decision-making deficits play essential roles in the development and maintenance of Internet gaming disorder (IGD). Clarifying whether impaired decision-making among individuals with IGD is related to poor inhibition will advance our understanding of IGD and contribute to intervention development. However, the relationship between these two functions remains unclear. In this study, we sought to systemically examine inhibitory processes, decision-making and the relationship between the two among individuals with IGD. Thirty-four individuals with IGD and 32 matched healthy controls (HCs) were recruited. In comparison to HCs, IGD subjects demonstrated inhibition deficits during performance of the gaming-related Go/No-Go task and impaired decision-making under risk. In addition, errors on No-Go trials during the gaming-related Go/No-Go task were positively associated with decision-making impairments under risk but not under ambiguity among IGD subjects. These results suggest individuals with IGD are impaired in some aspects of inhibition and decision-making functions, and that decision-making deficits under risk are linked to poor inhibition specifically related to gaming cues, which has implications for the development of novel intervention.


Assuntos
Comportamento Aditivo/psicologia , Tomada de Decisões , Internet , Estudantes/psicologia , Jogos de Vídeo/psicologia , Adulto , Comportamento Aditivo/diagnóstico , Estudos Transversais , Sinais (Psicologia) , Tomada de Decisões/fisiologia , Humanos , Masculino , Estimulação Luminosa/métodos , Projetos Piloto , Tempo de Reação/fisiologia , Assunção de Riscos , Universidades , Adulto Jovem
17.
PLoS One ; 10(1): e0116471, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25615595

RESUMO

Individuals with Internet gaming disorder (IGD) tend to exhibit disadvantageous risky decision-making not only in their real life but also in laboratory tasks. Decision-making is a complex multifaceted function and different cognitive processes are involved in decision-making for gains and losses. However, the relationship between impaired decision-making and gain versus loss processing in the context of IGD is poorly understood. The main aim of the present study was to separately evaluate decision-making for risky gains and losses among college students with IGD using the Cups task. Additionally, we further examined the effects of outcome magnitude and probability level on decision-making related to risky gains and losses respectively. Sixty college students with IGD and 42 matched healthy controls (HCs) participated. Results indicated that IGD subjects exhibited generally greater risk taking tendencies than HCs. In comparison to HCs, IGD subjects made more disadvantageous risky choices in the loss domain (but not in the gain domain). Follow-up analyses indicated that the impairment was associated to insensitivity to changes in outcome magnitude and probability level for risky losses among IGD subjects. In addition, higher Internet addiction severity scores were associated with percentage of disadvantageous risky options in the loss domain. These findings emphasize the effect of insensitivity to losses on disadvantageous decisions under risk in the context of IGD, which has implications for future intervention studies.


Assuntos
Tomada de Decisões/fisiologia , Assunção de Riscos , Estudantes/psicologia , Estudos de Casos e Controles , Humanos , Internet , Adulto Jovem
18.
Psychiatry Res ; 219(3): 583-8, 2014 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-25024056

RESUMO

Internet gaming addiction (IGA) is an increasing mental health issue worldwide. Previous studies have revealed decision-making impairments in excessive Internet gamers (EIGs) with high symptoms of IGA. However, the role of feedback processing in decision-making deficits among EIGs remains unknown. The present study aimed to investigate the effect of feedback processing on decision-making deficits under risk among EIGs, using the Game of Dice Task (GDT) and a modified version of the GDT in which no feedback was provided. Twenty-six EIGs and 26 matched occasional Internet gamers (OIGs) were recruited. The results showed: (a) OIGs performed better on the original GDT than on the modified GDT (no feedback condition); however, EIGs performed similarly on both tasks; (b) EIGs and OIGs performed equally on the modified GDT; however, EIGs chose more disadvantageous options than OIGs on the original GDT; (c) EIGs utilized feedback less frequently on the original GDT relative to OIGs. These results suggest that EIGs are not able to utilize feedback to optimize their decisions, which could underlie their poor decision-making under risk.


Assuntos
Comportamento Aditivo/psicologia , Tomada de Decisões , Retroalimentação Psicológica , Jogo de Azar/psicologia , Internet , Adolescente , Feminino , Jogos Experimentais , Humanos , Masculino , Testes Neuropsicológicos , Risco , Assunção de Riscos , Estudantes/psicologia , Adulto Jovem
19.
Ultrasonics ; 51(5): 602-5, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21272905

RESUMO

An analysis is given to the band structure of the two-dimensional phononic crystal plate constituted of a square array of elastic anisotropic, circular Pb cylinders embedded in elastic isotropic epoxy. The numerical results show that the band gap can be tuned by rotating the anisotropic material orientation. It is found that the influence of anisotropy on band gap of Lamb wave is clearly different from that on the band gap of bulk waves. The thickness of the system under study is a sensitive parameter to affect the influence of anisotropic materials on the normalized gap width.


Assuntos
Resinas Epóxi , Chumbo , Modelos Teóricos , Refratometria/métodos , Ultrassonografia/métodos , Anisotropia , Simulação por Computador , Cristalização , Espalhamento de Radiação
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