Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 64
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Pediatrics ; 144(5)2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31659003

RESUMO

OBJECTIVES: Electronic cigarette (e-cigarette) use has become increasingly prevalent among US youth and young adults in recent years. Exposure to e-cigarette marketing may stimulate e-cigarette use. In this study, we estimated the longitudinal association between e-cigarette marketing exposure and e-cigarette experimentation among US youth and young adult never tobacco users. METHODS: The analysis included nationally representative samples of youth (ages 12-17; n = 8121) and young adult (ages 18-24; n = 1683) never tobacco users from wave 2 (2014-2015) and wave 3 (2015-2016) of the Population Assessment of Tobacco and Health Study. In the study, researchers measured past-month exposure to e-cigarette marketing through various places (eg, Web sites and events) at wave 2 and e-cigarette experimentation at wave 3. Statistical analysis included multivariable regressions to examine the associations between wave 2 e-cigarette marketing exposure and wave 3 e-cigarette experimentation. RESULTS: At wave 2, 70.7% of youth and 73.9% of young adult never tobacco users reported past-month exposure to e-cigarette marketing; at wave 3, 4.9% and 4.5% of youth and young adults experimented with e-cigarettes, respectively. Youth and young adults exposed to e-cigarette marketing at wave 2 were more likely (adjusted odds ratio = 1.53, 95% confidence interval = 1.07-2.17; and adjusted odds ratio = 2.73, 95% confidence interval = 1.16-6.42, respectively) to have experimented with e-cigarettes at wave 3 than those not exposed. Marketing exposure through each place at wave 2 was associated with e-cigarette experimentation at wave 3. CONCLUSIONS: E-cigarette marketing exposure predicted subsequent e-cigarette experimentation among youth and young adult never tobacco users. Increased restrictions on marketing through various channels may help minimize their exposure to e-cigarette marketing messages.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina/estatística & dados numéricos , Marketing , Vaping/epidemiologia , Adolescente , Criança , Feminino , Humanos , Masculino , Inquéritos e Questionários , Estados Unidos/epidemiologia , Adulto Jovem
2.
Front Hum Neurosci ; 13: 310, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31551737

RESUMO

Relatively little attention has been paid to the neural basis of superior memory despite its potential in providing important insight into efforts to improve memory in the general population or to offset age-related cognitive decline. The current study reports a rare opportunity to reproduce and isolate specific neural activities directly associated with exceptional memory. To capture the brain processes responsible for superior memory, we returned to a laboratory task and analytic approach used to explore the nature of exceptional memory, namely, digit-span task combined with verbal protocol analysis. One participant with average memory received approximately 50 h of digit-span training and the participant's digit-span increased from normative (8 digits) to exceptional (30 digits). Event-related potentials were recorded while the participant's digit span increased from 19 to 30 digits. Protocol analysis allowed us to identify direct behavioral indices of idiosyncratic encoding processes underlying the superior memory performance. EEG indices directly corresponding to the behavioral indices of encoding processes were identified. The results suggest that the early attention-related encoding processes were reflected in theta and delta whereas the later attention-independent encoding processes were reflected in time-domain slow-wave. This fine-grained approach offers new insights into studying neural mechanism mediating superior memory and the cognitive effort necessary to develop it.

3.
J Affect Disord ; 257: 536-550, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31323595

RESUMO

BACKGROUND: Theories of suicide posit distinct etiological pathways for suicide attempts (SA) and suicidal ideation (SI) that are marked, in part, by disruptions in the ability to regulate reactions to threat/mutilation and interpersonally-relevant emotional stimuli. However, little research has specifically tested these associations. To address this gap, the present study extracted the Late Positive Potential (LPP) during an emotion regulation task to evaluate the independent associations that SA history and SI share with initial responsivity to, and regulation of, these distinct emotional contents. METHODS: A clinical sample (N = 257) were recruited based on elevations in suicide risk factors. Participants completed a picture viewing and regulation task that included threat/mutilation, reward, and neutral images from the International Affective Picture System. Immediately prior to picture onset, participants were instructed to passively view the image, increase their emotional reaction to the image, or decrease their emotional reaction to the image. RESULTS: Differential patterns of LPP amplitudes only emerged in the context of attempts to regulate emotional responses such that SA history predicted a superior ability to volitionally mitigate responses to threat/mutilation while SI was related to a worse ability to increase responses to reward. Effect sizes were in the small and small-to-medium range. LIMITATIONS: The present data were cross-sectional and included low trial counts. CONCLUSIONS: Taken together, these findings support existing theories of suicide suggesting that distinct mechanisms underlie suicidal thoughts and behaviors. Future research should seek to determine if these mechanisms may serve as a viable intervention targets.

4.
Neuroimage ; 198: 13-30, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31100431

RESUMO

Theta oscillations (4-8 Hz) provide an organizing principle of cognitive control, allowing goal-directed behavior. In adults, theta power over medial-frontal cortex (MFC) underlies conflict/error monitoring, whereas theta connectivity between MFC and lateral-frontal regions reflects cognitive control recruitment. However, prior work has not separated theta responses that occur before and immediately after a motor response, nor explained how medial-lateral connectivity drives different kinds of control behaviors. Theta's role during adolescence, a developmental window characterized by a motivation-control mismatch also remains unclear. As social observation is known to influence motivation, this might be a particularly important context for studying adolescent theta dynamics. Here, adolescents performed a flanker task alone or under social observation. Focusing first on the nonsocial context, we parsed cognitive control into dissociable subprocesses, illustrating how theta indexes distinct components of cognitive control working together dynamically to produce goal-directed behavior. We separated theta power immediately before/after motor responses, identifying behavioral links to conflict monitoring and error monitoring, respectively. MFC connectivity was separated before/after responses and behaviorally-linked to reactive and proactive control, respectively. Finally, distinct forms of post-error control were dissociated, based on connectivity with rostral/caudal frontal cortex. Social observation was found to exclusively upregulate theta measures indexing post-response error monitoring and proactive control, as opposed to conflict monitoring and reactive control. Linking adolescent cognitive control to theta oscillations provides a bridge between non-invasive recordings in humans and mechanistic studies of neural oscillations in animal models; links to social observation provide insight into the motivation-control interactions that occur during adolescence.


Assuntos
Encéfalo/fisiologia , Cognição/fisiologia , Função Executiva/fisiologia , Motivação/fisiologia , Infuência dos Pares , Ritmo Teta , Adolescente , Criança , Sincronização Cortical , Eletroencefalografia , Feminino , Humanos , Masculino
5.
Emotion ; 19(1): 70-83, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29553758

RESUMO

Anxiety sensitivity (AS), or the fear of anxious arousal, is a transdiagnostic risk factor predictive of a wide variety of affective disorders. Whereas AS is widely studied via self-report, the neurophysiological correlates of AS are poorly understood. One specific issue this may help resolve is well-established gender differences in mean levels of AS. The current study evaluated late positive potential (LPP) for images designed to target AS during an emotional picture viewing paradigm. Structural equation modeling was used to examine convergent and discriminant validity for self-report AS and the LPP for AS images, considering gender as a potential moderator. Analyses were conducted in an at-risk sample of 251 community adults (M age = 35.47, SD = 15.95; 56.2% female; 53.6% meeting for a primary Axis I anxiety or related disorder). Findings indicated that the AS image LPP was significantly, uniquely associated with self-report AS, controlling for the LPP for unpleasant images, in females only. Mean levels of AS self-report as well as the AS image LPP were higher in females than in males. These findings provide initial support for the AS image LPP as a useful neurophysiological correlate of AS self-report in females. These findings also provide support for a biological cause for gender differences in AS. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Assuntos
Ansiedade/psicologia , Emoções/fisiologia , Potenciais Evocados/fisiologia , Adulto , Feminino , Identidade de Gênero , Humanos , Masculino , Autorrelato
6.
Clin Psychol Rev ; 69: 83-96, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-29680185

RESUMO

There is a tremendous global and national (US) burden associated with alcohol misuse and alcohol use disorder (AUD). Further, of the mental health disorders, AUD has the widest treatment gap. Thus, there is a critical need for improved understanding of the etiology, maintenance, and treatment of AUD. The application of cognitive science to the study of AUD has a longstanding history of attempting to meet this need. In this selective review, we identified and focused on four domains of recent (i.e., in the last decade) applications of cognitive science to the study of AUD: implicit cognitive biases, executive function, behavioral economic approaches to alcohol decision making, and functional connectivity neuroimaging. We highlighted advances within these four domains and considered them in the context of dual process models of addiction, which focus on the contribution and interplay of two complementary neurocognitive systems (impulsive and control systems). Findings across the domains were generally consistent with dual process models. They also suggest the need for further model refinements, including integrating behavioral economic approaches and findings from functional connectivity neuroimaging studies. Research evaluating candidate interventions associated with these domains is emergent but promising, suggesting important directions for future research.

7.
Psychophysiology ; 55(9): e13195, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29750361

RESUMO

The role of reward context has been investigated as an important factor in feedback processing. Previous work has demonstrated that the amplitude of the feedback negativity (FN) depends on the value of the outcome relative to the range of possible outcomes in a given context, not the objective value of the outcome. However, some research has shown that the FN does not scale with loss magnitude in loss-only contexts, suggesting that some contexts do not show a pattern of context dependence. Methodologically, time-frequency decomposition techniques have proven useful for isolating time-domain ERP activity as separable processes indexed in delta (< 3 Hz) and theta (3-7 Hz). Thus, the current study assessed the role of context in a modified gambling feedback task using time-frequency analysis to better isolate the underlying processes. Results revealed that theta was more context dependent and reflected a binary evaluation of bad versus good outcomes in the gain and even contexts. Delta was more context independent: good outcomes scaled linearly with reward magnitude and good-bad differences scaled with context valence. Our findings reveal that theta and delta are differentially sensitive to context and that context valence may play a critical role in determining how the brain processes feedback.


Assuntos
Ondas Encefálicas/fisiologia , Córtex Cerebral/fisiologia , Comportamento de Escolha/fisiologia , Potenciais Evocados/fisiologia , Retroalimentação Psicológica/fisiologia , Desempenho Psicomotor/fisiologia , Recompensa , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
8.
Int J Psychophysiol ; 132(Pt B): 203-212, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29719202

RESUMO

The neurophysiological mechanisms involved in the evaluation of performance feedback have been widely studied in the ERP literature over the past twenty years, but understanding has been limited by the use of traditional time-domain amplitude analytic approaches. Gambling outcome valence has been identified as an important factor modulating event-related potential (ERP) components, most notably the feedback negativity (FN). Recent work employing time-frequency analysis has shown that processes indexed by the FN are confounded in the time-domain and can be better represented as separable feedback-related processes in the theta (3-7 Hz) and delta (0-3 Hz) frequency bands. In addition to time-frequency amplitude analysis, phase synchrony measures have begun to further our understanding of performance evaluation by revealing how feedback information is processed within and between various brain regions. The current study aimed to provide an integrative assessment of time-frequency amplitude, inter-trial phase synchrony, and inter-channel phase synchrony changes following monetary feedback in a gambling task. Results revealed that time-frequency amplitude activity explained separable loss and gain processes confounded in the time-domain. Furthermore, phase synchrony measures explained unique variance above and beyond amplitude measures and demonstrated enhanced functional integration between medial prefrontal and bilateral frontal, motor, and occipital regions for loss relative to gain feedback. These findings demonstrate the utility of assessing time-frequency amplitude, inter-trial phase synchrony, and inter-channel phase synchrony together to better elucidate the neurophysiology of feedback processing.


Assuntos
Córtex Cerebral/fisiologia , Ritmo Delta/fisiologia , Sincronização de Fases em Eletroencefalografia/fisiologia , Função Executiva/fisiologia , Retroalimentação Psicológica/fisiologia , Ritmo Teta/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Adulto Jovem
9.
Biol Psychol ; 136: 1-12, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29729300

RESUMO

The feedback negativity (FN) event-related potential (ERP) is widely studied during gambling feedback tasks. However, research on FN and anxiety is minimal and the findings are mixed. To clarify these discrepancies, the current study (N = 238) used time-frequency analysis to disentangle overlapping contributions of delta (0-3 Hz) and theta (3-7 Hz) to feedback processing in a clinically anxious sample, with severity assessed through general worry and physiological arousal scales. Greater general worry showed enhanced delta- and theta-FN broadly across both gain and loss conditions, with theta-FN stronger for losses. Regressions indicated delta-FN maintained unique effects, accounted for theta, and explained the blunted time domain FN for general worry. Increased delta was also associated with physiological arousal, but the effects were accounted for by general worry. Broadly, anxiety-related alterations in feedback processing can be explained by an overall heightened sensitivity to feedback as represented by enhanced delta-FN in relation to the general worry facet of anxiety.


Assuntos
Ansiedade/psicologia , Ritmo Delta , Retroalimentação Psicológica , Jogo de Azar/psicologia , Ritmo Teta , Adulto , Nível de Alerta , Manual Diagnóstico e Estatístico de Transtornos Mentais , Eletroencefalografia , Potenciais Evocados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autorrelato
10.
Int J Psychophysiol ; 128: 70-80, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29574233

RESUMO

A growing body of work suggests that the P300 (P3) event-related potential (ERP) component is better understood as a mixture of task-relevant processes (Polich, 2007). This converges with earlier time-frequency work suggesting that the P3b is primarily composed of centroparietal delta (0.5-3 Hz) and frontocentral theta (3-7 Hz) activity. Within this study (N = 229), we hope to re-affirm these prior ideas and expand upon them in several crucial ways, reassessing how delta and theta contribute to the visual oddball P3b through the lens of several recent decades of additional P3b research. We provide a comprehensive assessment of how theta and delta time-frequency activity contribute to several common variants of the time-domain P3b, specifically measuring the target and non-target P3b, as well as differences between targets and non-targets, target-to-target interval (TTI), and target habituation. Results replicate and extend earlier work indicating that delta and theta account for a majority of variance in both the target and non-target P3b as well as their respective amplitude differences. They also newly indicate that theta and delta activity can have unique contributions to TTI differences and target habituation effects. Results in target habituation particularly demonstrate how time-frequency analyses can disentangle nuanced changes in P3b activity, shedding new light on these complicated phenomena. Findings suggest that delta and theta measures index separable processes occurring during the P3b, and provide additional support for the idea that they index theoretical frontocentral and centroparietal P3 subcomponents.


Assuntos
Córtex Cerebral/fisiologia , Ritmo Delta/fisiologia , Eletroencefalografia/métodos , Potencial Evocado P300/fisiologia , Habituação Psicofisiológica/fisiologia , Desempenho Psicomotor/fisiologia , Ritmo Teta/fisiologia , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
11.
J Abnorm Psychol ; 127(1): 12-29, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29369665

RESUMO

Distress intolerance (DI), a trait-like individual difference reflective of the inability to endure aversive affective states, is relevant to multiple forms of psychopathology, but its relations to theoretically relevant neurobiological systems have received little attention. Altered cognitive control-related neurobiology has been theorized to underlie individual differences in DI, but little empirical work has been conducted. To test this hypothesis, baseline data from a large community sample with elevated high levels of emotional psychopathology and comorbidity was utilized (N = 256). Participants completed a complex go/no-go task while EEG was recorded, and P2, N2, and P3 amplitudes were measured. Based upon prior findings on the relations between these components and response inhibition, a core cognitive control function, we hypothesized that DI would predict reduced no-go N2 and P3 amplitude while controlling for current anxious/depressive symptom severity (i.e., negative affect). Peak amplitudes from the raw data and principal components analysis were used to quantify amplitude of ERP components. Partially consistent with predictions, high DI was independently associated with reduced no-go N2 peak amplitude in the raw ERP data, and was significantly related to a frontal positivity factor in the N2 time window across no-go and go trials. Contrary to predictions, no relations between DI and the P3 were found. Overall, results support the theorized relevance of cognitive control-linked neurobiology to individual differences in tolerance of distress over and above distress severity itself, and suggest specific relations between DI and alterations in early controlled attention/conflict-monitoring but not response inhibition or response inhibition-related sequelae. (PsycINFO Database Record


Assuntos
Encéfalo/fisiopatologia , Função Executiva , Personalidade , Desempenho Psicomotor , Estresse Psicológico , Adulto , Eletroencefalografia , Potenciais Evocados , Feminino , Humanos , Individualidade , Masculino , Testes Neuropsicológicos
12.
Clin Neurophysiol ; 129(1): 210-221, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29197736

RESUMO

OBJECTIVE: To better understand the origins of working memory (WM) impairment in schizophrenia we investigated cortical oscillatory activity in people with schizophrenia (PSZ) while they performed a WM task requiring encoding, maintenance, and retrieval/manipulation processes of spatial information. METHODS: We examined time-frequency synchronous energy of cortical source signals that were derived from magnetoencephalography (MEG) localized to cortical regions using WM-related hemodynamic responses and individualized structural head-models. RESULTS: Compared to thirteen healthy controls (HC), twelve PSZ showed performance deficits regardless of WM-load or duration. During encoding, PSZ had early theta and delta event-related synchrony (ERS) deficits in prefrontal and visual cortices which worsened with greater memory load and predicted WM performance. During prolonged maintenance of material, PSZ showed deficient beta event-related desynchrony (ERD) in dorsolateral prefrontal, posterior parietal, and visual cortices. In retrieval, PSZ showed reduced delta/theta ERS in the anterior prefrontal and ventral visual cortices and diminished gamma ERS in the premotor and posterior parietal cortices. CONCLUSIONS: Although beta/gamma cortical neural oscillatory deficits for maintenance/retrieval are evident during WM, the abnormal prefrontal theta-frequency ERS for encoding is most predictive of poor WM in schizophrenia. SIGNIFICANCE: Time-frequency-spatial analysis identified process- and frequency-specific neural synchrony abnormalities underlying WM deficits in schizophrenia.


Assuntos
Sincronização Cortical , Memória de Curto Prazo , Esquizofrenia/fisiopatologia , Adulto , Ondas Encefálicas , Estudos de Casos e Controles , Feminino , Humanos , Magnetoencefalografia , Masculino , Pessoa de Meia-Idade
13.
Biol Psychol ; 129: 242-252, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28865935

RESUMO

The roles of outcome valence and expectancy in feedback processing have been investigated as important factors modulating event-related potential (ERP) measures including the feedback negativity (FN) and P300, but results have been inconsistent. Recent work from our group has shown that processes underlying the FN and P300 are better represented as separable processes in the theta (3-7Hz) and delta (0-3Hz) ranges using time-frequency analysis. The current study evaluated the modulation of time-domain FN and P300 and time-frequency theta and delta to outcome valence and expectancy in a gambling feedback task paradigm. Results revealed that the FN was sensitive to valence but not expectancy, and that valence effects were driven by loss-sensitive theta and gain-sensitive delta. Alternatively, the P300 was sensitive to the expectedness of outcomes but only for gain trials, and these expectancy differences were explained by time-frequency delta not theta. These results add to a growing body of research showing that time-frequency measures reflect separable processes underlying time-domain components, where theta is more sensitive to primary task features and less sensitive to secondary features while delta is sensitive to primary and more complex, secondary task features.


Assuntos
Encéfalo/fisiologia , Potenciais Evocados/fisiologia , Retroalimentação Psicológica/fisiologia , Adolescente , Eletroencefalografia , Feminino , Jogo de Azar/fisiopatologia , Humanos , Masculino , Adulto Jovem
14.
Brain ; 140(7): 2041-2050, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28582479

RESUMO

Post-traumatic stress disorder is characterized by exaggerated threat response, and theoretical accounts to date have focused on impaired threat processing and dysregulated prefrontal-cortex-amygdala circuitry. Nevertheless, evidence is accruing for broad, threat-neutral sensory hyperactivity in post-traumatic stress disorder. As low-level, sensory processing impacts higher-order operations, such sensory anomalies can contribute to widespread dysfunctions, presenting an additional aetiological mechanism for post-traumatic stress disorder. To elucidate a sensory pathology of post-traumatic stress disorder, we examined intrinsic visual cortical activity (based on posterior alpha oscillations) and bottom-up sensory-driven causal connectivity (Granger causality in the alpha band) during a resting state (eyes open) and a passive, serial picture viewing state. Compared to patients with generalized anxiety disorder (n = 24) and healthy control subjects (n = 20), patients with post-traumatic stress disorder (n = 25) demonstrated intrinsic sensory hyperactivity (suppressed posterior alpha power, source-localized to the visual cortex-cuneus and precuneus) and bottom-up inhibition deficits (reduced posterior→frontal Granger causality). As sensory input increased from resting to passive picture viewing, patients with post-traumatic stress disorder failed to demonstrate alpha adaptation, highlighting a rigid, set mode of sensory hyperactivity. Interestingly, patients with post-traumatic stress disorder also showed heightened frontal processing (augmented frontal gamma power, source-localized to the superior frontal gyrus and dorsal cingulate cortex), accompanied by attenuated top-down inhibition (reduced frontal→posterior causality). Importantly, not only did suppressed alpha power and bottom-up causality correlate with heightened frontal gamma power, they also correlated with increased severity of sensory and executive dysfunctions (i.e. hypervigilance and impulse control deficits, respectively). Therefore, sensory aberrations help construct a vicious cycle in post-traumatic stress disorder that is in action even at rest, implicating dysregulated triangular sensory-prefrontal-cortex-amygdala circuitry: intrinsic sensory hyperactivity and disinhibition give rise to frontal overload and disrupt executive control, fuelling and perpetuating post-traumatic stress disorder symptoms. Absent in generalized anxiety disorder, these aberrations highlight a unique sensory pathology of post-traumatic stress disorder (ruling out effects merely reflecting anxious hyperarousal), motivating new interventions targeting sensory processing and the sensory brain in these patients.


Assuntos
Inibição Neural/fisiologia , Descanso/fisiologia , Transtornos das Sensações/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Córtex Visual/fisiopatologia , Adulto , Ritmo alfa/fisiologia , Transtornos de Ansiedade/fisiopatologia , Estudos de Casos e Controles , Função Executiva/fisiologia , Feminino , Lobo Frontal/fisiopatologia , Ritmo Gama/fisiologia , Giro do Cíngulo/fisiopatologia , Humanos , Masculino , Estimulação Luminosa , Transtornos das Sensações/complicações , Transtornos de Estresse Pós-Traumáticos/complicações , Percepção Visual/fisiologia , Adulto Jovem
15.
IEEE Trans Biomed Eng ; 64(1): 225-237, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27093314

RESUMO

Functional connectivity (FC), defined as the statistical dependency between distinct brain regions, has been an important tool in understanding cognitive brain processes. Most of the current works in FC have focused on the assumption of temporally stationary networks. However, recent empirical work indicates that FC is dynamic due to cognitive functions. GOAL: The purpose of this paper is to understand the dynamics of FC for understanding the formation and dissolution of networks of the brain. METHOD: In this paper, we introduce a two-step approach to characterize the dynamics of functional connectivity networks (FCNs) by first identifying change points at which the network connectivity across subjects shows significant changes and then summarizing the FCNs between consecutive change points. The proposed approach is based on a tensor representation of FCNs across time and subjects yielding a four-mode tensor. The change points are identified using a subspace distance measure on low-rank approximations to the tensor at each time point. The network summarization is then obtained through tensor-matrix projections across the subject and time modes. RESULTS: The proposed framework is applied to electroencephalogram (EEG) data collected during a cognitive control task. The detected change-points are consistent with a priori known ERN interval. The results show significant connectivities in medial-frontal regions which are consistent with widely observed ERN amplitude measures. CONCLUSION: The tensor-based method outperforms conventional matrix-based methods such as singular value decomposition in terms of both change-point detection and state summarization. SIGNIFICANCE: The proposed tensor-based method captures the topological structure of FCNs which provides more accurate change-point-detection and state summarization.


Assuntos
Algoritmos , Mapeamento Encefálico/métodos , Córtex Cerebral/fisiologia , Eletroencefalografia/métodos , Modelos Neurológicos , Rede Nervosa/fisiologia , Simulação por Computador , Diagnóstico por Computador/métodos , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
Int J Psychophysiol ; 111: 88-97, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27864029

RESUMO

Time-frequency signal processing approaches are well-developed, and have been widely employed for the study of the energy distribution of event-related potential (ERP) data across time and frequency. Wavelet time-frequency transform (TFT) and Cohen's class of time-frequency distributions (TFD) are the most widely used in the field. While ERP TFT approaches have been most extensively developed for amplitude measures, reflecting the magnitude of regional neuronal activity, time-frequency phase-synchrony measures have gained increased utility in recent years for the assessment of functional connectivity. Phase synchrony measures can be used to index the functional integration between regions (interregional), in addition to the consistency of activity within region (intertrial). In this paper, we focus on a particular class of time-frequency distributions belonging to Cohen's class, known as the Reduced Interference Distribution (RID) for quantifying functional connectivity, which we recently introduced (Aviyente et al., 2011). The present report first summarizes common time-frequency approaches to computing phase-synchrony with ERP data in order to highlight the similarities and differences relative to the RID. In previous work, we demonstrated differences between the RID and wavelet approaches to indexing phase-synchrony, and have applied the RID to demonstrate that RID-based time-frequency phase-synchrony measures can index increased functional connectivity between medial and lateral prefrontal regions during control processing, observed in the theta band during the error-related negativity (ERN). Because ERN amplitude measures have been associated with two other widely studied medial-frontal theta components (no-go N2; feedback negativity, FN), the application of the RID phase synchrony measure in the present report extends our previous work with ERN to include theta activity during the no-go N2 (inhibitory processing) and the feedback negativity (FN; loss feedback processing). Findings support the idea that similar medial-lateral prefrontal functional connectivity underlies the ERN, no-go N2, and FN components, and provide initial validation that the proposed RID-based time-frequency phase-synchrony measure can index this activity.


Assuntos
Sincronização de Fases em Eletroencefalografia/fisiologia , Potenciais Evocados/fisiologia , Função Executiva/fisiologia , Córtex Pré-Frontal/fisiologia , Ritmo Teta/fisiologia , Adulto , Humanos , Adulto Jovem
17.
Neuroimage ; 132: 247-260, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-26908319

RESUMO

Error-related brain activity has become an increasingly important focus of cognitive neuroscience research utilizing both event-related potentials (ERPs) and functional magnetic resonance imaging (fMRI). Given the significant time and resources required to collect these data, it is important for researchers to plan their experiments such that stable estimates of error-related processes can be achieved efficiently. Reliability of error-related brain measures will vary as a function of the number of error trials and the number of participants included in the averages. Unfortunately, systematic investigations of the number of events and participants required to achieve stability in error-related processing are sparse, and none have addressed variability in sample size. Our goal here is to provide data compiled from a large sample of healthy participants (n=180) performing a Go/NoGo task, resampled iteratively to demonstrate the relative stability of measures of error-related brain activity given a range of sample sizes and event numbers included in the averages. We examine ERP measures of error-related negativity (ERN/Ne) and error positivity (Pe), as well as event-related fMRI measures locked to False Alarms. We find that achieving stable estimates of ERP measures required four to six error trials and approximately 30 participants; fMRI measures required six to eight trials and approximately 40 participants. Fewer trials and participants were required for measures where additional data reduction techniques (i.e., principal component analysis and independent component analysis) were implemented. Ranges of reliability statistics for various sample sizes and numbers of trials are provided. We intend this to be a useful resource for those planning or evaluating ERP or fMRI investigations with tasks designed to measure error-processing.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Potenciais Evocados , Adolescente , Adulto , Ondas Encefálicas , Eletroencefalografia , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Processamento de Sinais Assistido por Computador , Adulto Jovem
18.
Psychophysiology ; 53(5): 712-22, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26751830

RESUMO

Recent work suggests that dissociable activity in theta and delta frequency bands underlies several common ERP components, including the no-go N2/P3 complex, which can better index separable functional processes than traditional time-domain measures. Reports have also demonstrated that neural activity can be affected by stimulus sequence context information (i.e., the number and type of preceding stimuli). Stemming from prior work demonstrating that theta and delta index separable processes during response inhibition, the current study assessed sequence context in a go/no-go paradigm in which the number of go stimuli preceding each no-go was selectively manipulated. Principal component analysis of time-frequency representations revealed differential modulation of evoked theta and delta related to sequence context, where delta increased robustly with additional preceding go stimuli, while theta did not. Findings are consistent with the view that theta indexes simpler initial salience-related processes, while delta indexes more varied and complex processes related to a variety of task parameters.


Assuntos
Encéfalo/fisiologia , Ritmo Delta/fisiologia , Potenciais Evocados/fisiologia , Ritmo Teta/fisiologia , Adolescente , Mapeamento Encefálico , Eletroencefalografia , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Estimulação Luminosa , Tempo de Reação/fisiologia , Adulto Jovem
19.
Personal Disord ; 7(1): 80-90, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26479259

RESUMO

Psychopathy is a serious personality disorder characterized by dysfunctional affective and behavioral symptoms. In incarcerated populations, elevated psychopathic traits have been linked to increased rates of violent recidivism. Cognitive processes related to error processing have been shown to differentiate individuals with high and low psychopathic traits and may contribute to poor decision making that increases the risk of recidivism. Error processing abnormalities related to psychopathy may be attributable to error-monitoring (error detection) or posterror processing (error evaluation). A recent 'bottleneck' theory predicts deficiencies in posterror processing in individuals with high psychopathic traits. In the current study, incarcerated males (n = 93) performed a Go/NoGo response inhibition task while event-related potentials (ERPs) were recorded. Classic time-domain windowed component and principal component analyses were used to measure error-monitoring (as measured with the error-related negativity [ERN/Ne]) and posterror processing (as measured with the error positivity [Pe]). Psychopathic traits were assessed using Hare's Psychopathy Checklist-Revised (PCL-R). PCL-R Total score, Factor 1 (interpersonal-affective traits), and Facet 3 (lifestyle traits) scores were positively related to posterror processes (i.e., increased Pe amplitude) but unrelated to error-monitoring processes (i.e., ERN/Ne). These results support the attentional bottleneck theory and further describe deficiencies related to elevated psychopathic traits that could be beneficial for new treatment strategies for psychopathy.


Assuntos
Transtorno da Personalidade Antissocial/fisiopatologia , Potenciais Evocados/fisiologia , Função Executiva/fisiologia , Prisioneiros/psicologia , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
20.
Soc Cogn Affect Neurosci ; 11(7): 1059-68, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26060326

RESUMO

Neurocognitive studies of psychopathy have predominantly focused on male samples. Studies have shown that female psychopaths exhibit similar affective deficits as their male counterparts, but results are less consistent across cognitive domains including response modulation. As such, there may be potential gender differences in error-related processing in psychopathic personality. Here we investigate response-locked event-related potential (ERP) components [the error-related negativity (ERN/Ne) related to early error-detection processes and the error-related positivity (Pe) involved in later post-error processing] in a sample of incarcerated adult female offenders (n = 121) who performed a response inhibition Go/NoGo task. Psychopathy was assessed using the Hare Psychopathy Checklist-Revised (PCL-R). The ERN/Ne and Pe were analyzed with classic windowed ERP components and principal component analysis (PCA). Consistent with previous research performed in psychopathic males, female psychopaths exhibited specific deficiencies in the neural correlates of post-error processing (as indexed by reduced Pe amplitude) but not in error monitoring (as indexed by intact ERN/Ne amplitude). Specifically, psychopathic traits reflecting interpersonal and affective dysfunction remained significant predictors of both time-domain and PCA measures reflecting reduced Pe mean amplitude. This is the first evidence to suggest that incarcerated female psychopaths exhibit similar dysfunctional post-error processing as male psychopaths.


Assuntos
Transtorno da Personalidade Antissocial/fisiopatologia , Transtorno da Personalidade Antissocial/psicologia , Adulto , Afeto , Criminosos/psicologia , Eletroencefalografia , Potenciais Evocados , Feminino , Humanos , Relações Interpessoais , Masculino , Testes Neuropsicológicos , Análise de Componente Principal , Desempenho Psicomotor , Tempo de Reação , Caracteres Sexuais
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA