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1.
Artigo em Inglês | MEDLINE | ID: mdl-38532040

RESUMO

RATIONALE: For decades, cannabis has been the most widely used illicit substance in the world, particularly among youth. Research suggests that mental health problems associated with cannabis use may result from its effect on reward brain circuit, emotional processes, and cognition. However, findings are mostly derived from correlational studies and inconsistent, particularly in adolescents. OBJECTIVES AND METHODS: Using data from the IMAGEN study, participants (non-users, persistent users, abstinent users) were classified according to their cannabis use at 19 and 22 years-old. All participants were cannabis-naïve at baseline (14 years-old). Psychopathological symptoms, cognitive performance, and brain activity while performing a Monetary Incentive Delay task were used as predictors of substance use and to analyze group differences over time. RESULTS: Higher scores on conduct problems and lower on peer problems at 14 years-old (n = 318) predicted a greater likelihood of transitioning to cannabis use within 5 years. At 19 years of age, individuals who consistently engaged in low-frequency (i.e., light) cannabis use (n = 57) exhibited greater conduct problems and hyperactivity/inattention symptoms compared to non-users (n = 52) but did not differ in emotional symptoms, cognitive functioning, or brain activity during the MID task. At 22 years, those who used cannabis at both 19 and 22 years-old n = 17), but not individuals that had been abstinent for ≥ 1 month (n = 19), reported higher conduct problems than non-users (n = 17). CONCLUSIONS: Impairments in reward-related brain activity and cognitive functioning do not appear to precede or succeed cannabis use (i.e., weekly, or monthly use). Cannabis-naïve adolescents with conduct problems and more socially engaged with their peers may be at a greater risk for lighter yet persistent cannabis use in the future.

2.
J Psychopathol Clin Sci ; 132(7): 867-880, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37338437

RESUMO

The organization of the Hierarchical Taxonomy of Psychopathology (HiTOP) model provides unique opportunities to evaluate whether neural risk measures operate as indicators of broader latent liabilities (e.g., externalizing proneness) or narrower expressions (e.g., antisociality and alcohol abuse). Following this approach, the current study recruited a sample of 182 participants (54% female) who completed measures of externalizing psychopathology (also internalizing) and associated traits. Participants also completed three tasks (Flanker-No Threat, Flanker-Threat, and Go/No-Go tasks) with event-related potential (ERP) measurement. Three variants of two research domain criteria (RDoC)-based neurophysiological indicators-P3 and error-related negativity (ERN)-were extracted from these tasks and used to model two latent ERP factors. Scores on these two ERP factors independently predicted externalizing factor scores when accounting for their covariance with sex-suggesting distinct neural processes contributing to the broad externalizing factor. No predictive relation with the broad internalizing factor was found for either ERP factor. Analyses at the finer-grained level revealed no unique predictive relations of either ERP factor with any specific externalizing symptom variable when accounting for the broad externalizing factor, indicating that ERN and P3 index general liability for problems in this spectrum. Overall, this study provides new insights about neural processes in externalizing psychopathology at broader and narrower levels of the HiTOP hierarchy. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

3.
Cogn Affect Behav Neurosci ; 23(3): 522-542, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37173606

RESUMO

Risk and uncertainty are central concepts of decision neuroscience. However, a comprehensive review of the literature shows that most studies define risk and uncertainty in an unclear fashion or use both terms interchangeably, which hinders the integration of the existing findings. We suggest uncertainty as an umbrella term that comprises scenarios characterized by outcome variance where relevant information about the type and likelihood of outcomes may be somewhat unavailable (ambiguity) and scenarios where the likelihood of outcomes is known (risk).These conceptual issues are problematic for studies on the temporal neurodynamics of decision-making under risk and ambiguity, because they lead to heterogeneity in task design and the interpretation of the results. To assess this problem, we conducted a state-of-the-art review of ERP studies on risk and ambiguity in decision-making. By employing the above definitions to 16 reviewed studies, our results suggest that: (a) research has focused more on risk than ambiguity processing; (b) studies assessing decision-making under risk often implemented descriptive-based paradigms, whereas studies assessing ambiguity processing equally implemented descriptive- and experience-based tasks; (c) descriptive-based studies link risk processing to increased frontal negativities (e.g., N2, N400) and both risk and ambiguity to reduced parietal positivities (e.g., P2, P3); (d) experience-based studies link risk to increased P3 amplitudes and ambiguity to increased frontal negativities and the LPC component; (e) both risk and ambiguity processing seem to be related with cognitive control, conflict monitoring, and increased cognitive demand; (f) further research and improved tasks are needed to dissociate risk and ambiguity processing.

4.
Front Aging Neurosci ; 13: 695275, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34803649

RESUMO

Subjective memory complaints (SMCs) may affect decision-making processes. This study aimed to investigate the neuronal correlates of feedback processing during a decision-making task in young and older adults with and without SMCs. Event-related potentials and behavioral performance during the Iowa gambling task were recorded in a total of 136 participants (65 young adults, 71 older adults). The participants were divided into two groups according to their SMCs (with SMCs: n = 60, without SMCs: n = 76). Feedback-related negativity (FRN) and P3 were analyzed in the feedback stage of the decision-making process. Older adults with SMCs scored worse in the ambiguity phase than older adults without SMCs. The FRN latency was longer for losses in older people with SMCs than in older people without SMCs in the first block. No significant differences between young and older adults with and without SMCs were observed in the other ERP measures. Compared to young adults, older adults showed delayed latency in the FRN component and reduced amplitudes and delayed latency in the P3 component. In conclusion, older people with SMCs present deficits in the decision-making process. These deficits are observed at the behavioral level, but also in neural mechanisms of early feedback processing of negative outcomes.

5.
Sci Rep ; 11(1): 11314, 2021 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-34059736

RESUMO

Subjective memory complaints (SMCs) are commonly related to aging, but they are also presented by young adults. Their neurophysiological mechanisms are not thoroughly understood, although some aspects related to affective state have been mentioned. Here, we investigated whether facial emotion processing is different in young people with (n = 41) and without (n = 39) SMCs who were exposed to positive, negative, and neutral faces, by recording the event-related potential (ERP) activity. From the ERP activity, the N170 (an index of face processing) and the LPP (an index of motivated attention) components were extracted. Regarding the N170, results showed less amplitude for positive and neutral faces in the participants with SMCs than in those without SMCs. Moreover, women with SMCs displayed longer latencies for neutral faces than women without SMCs. No significant differences were found between the groups in the LPP component. Together, our findings suggest deficits in an early stage of facial emotion processing in young people with SMCs, and they emphasize the importance of further examining affective dimensions.


Assuntos
Potenciais Evocados , Reconhecimento Facial/fisiologia , Transtornos da Memória/fisiopatologia , Adolescente , Adulto , Estudos de Casos e Controles , Autoavaliação Diagnóstica , Feminino , Humanos , Masculino , Adulto Jovem
6.
Front Psychol ; 12: 633555, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34054645

RESUMO

The containment measures imposed during the first COVID-19 outbreak required economic, social, and behavioral changes to minimize the spread of the coronavirus. Some studies have focused on how personality predicts distinct patterns of adherence to protective measures with psychopathic and antisocial traits predicting reduced engagement in such measures. In this study we extended previous findings by analyzing how boldness, meanness, and disinhibition psychopathic traits relate with both risk perceptions and protective behaviors during the first COVID-19 outbreak. A sample of 194 individuals (24% male) engaged in the survey, were assessed for psychopathic traits with the Triarchic Psychopathy Measure, and completed a COVID-19 survey targeting risk perceptions (spread, risk of becoming infected, state anxiety toward the COVID-19, and perceived risk of specific behaviors) and frequency of protective behaviors (e.g., not engaging in social distancing). Overall results show that boldness predicts reduced estimate of COVID-19 spread, reduced perceived risk of becoming infected, reduced state anxiety toward COVID-19, and reduced frequency of protective behaviors. Exploratory mediation models suggest that risk perceptions are not significant mediators of the association between psychopathic traits and reduced engagement in protective behaviors. Our results unveil that psychopathic traits affect risk perceptions and the propensity to engage in protective measures, emphasizing the need to accommodate these personality features in the public health strategy to control the COVID-19 spread.

7.
Front Psychiatry ; 12: 630406, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33815168

RESUMO

Auditory event-related potentials (ERP) may serve as diagnostic tools for schizophrenia and inform on the susceptibility for this condition. Particularly, the examination of N1 and P2 components of the auditory ERP may shed light on the impairments of information processing streams in schizophrenia. However, the habituation properties (i.e., decreasing amplitude with the repeated presentation of an auditory stimulus) of these components remain poorly studied compared to other auditory ERPs. Therefore, the current study used a roving paradigm to assess the modulation and habituation of N1 and P2 to simple (pure tones) and complex sounds (human voices and bird songs) in 26 first-episode patients with schizophrenia and 27 healthy participants. To explore the habituation properties of these ERPs, we measured the decrease in amplitude over a train of seven repetitions of the same stimulus (either bird songs or human voices). We observed that, for human voices, N1 and P2 amplitudes decreased linearly from stimulus 1-7, in both groups. Regarding bird songs, only the P2 component showed a decreased amplitude with stimulus presentation, exclusively in the control group. This suggests that patients did not show a fading of neural responses to repeated bird songs, reflecting abnormal habituation to this stimulus. This could reflect the inability to inhibit irrelevant or redundant information at later stages of auditory processing. In turn schizophrenia patients appear to have a preserved auditory processing of human voices.

8.
Front Psychol ; 11: 561785, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33178069

RESUMO

COVID-19 outbreak is a sudden and devastating global pandemic in which the control of the spread is highly dependent on individual reactions, until the development of a vaccine and adequate treatments. Considering that older adults are at high risk for COVID-related medical complications and mortality, the present study focuses on the age-related differences on the adoption of protective behaviors during the initial stages of this outbreak, while accounting for the role of sociodemographic, COVID-related, perceived risk, and psychosocial variables (i.e., anxiety, optimism, fear of death, and social isolation) in this relation. The study sample included 1696 participants, aged between 18 and 85 years old, who completed an online survey during the initial stages of the first COVID-19 outbreak in Portugal. Overall, results reveal that the engagement in protective behaviors declines with advancing age and that older adults show a pattern toward lower perceived risk compared with middle-aged adults. Multicategorical mediation analyses show that anxiety, optimism, fear of death, and social isolation significantly mediate age effects on protective behaviors. Specifically, both anxiety and fear of death increase protective behaviors via higher perceived risk in the middle-aged and in the younger groups, respectively. Optimism directly predicts protective behaviors in the middle-aged groups, while social isolation reduces protective behaviors in the younger and older-aged groups. Results are discussed in terms of its implications for public health policies.

9.
Psychophysiology ; 57(8): e13567, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32167178

RESUMO

The psychopathic traits boldness, meanness, and disinhibition are theorized to be underlined by trait fearlessness and externalizing vulnerability as etiologic neurobiological processes. However, little is known about the neurophysiological correlates of these traits. In this work, we explored how the three traits are associated with event-related potential (ERP) components targeted at the etiological processes in a partial delayed threat conditioning task and in a go/no-go task. Fifty community-dwelling volunteers (25 women), without history of neurological or psychiatric conditions, were recruited and assessed for psychopathic traits using the triarchic psychopathy measure. Participants performed a threat conditioning task, and a go/no-go task while undergoing an electroencephalography recording. Results from the threat conditioning task showed that boldness was significantly associated with reduced late positive potential. Concerning the go/no-go task, disinhibition was significantly associated with reduced error-related negativity ERP component. Overall, distinct psychopathic traits were found to be associated with distinct neurophysiological correlates of threat conditioning and response inhibition. This is consistent with models of psychopathy entailing trait fearlessness and externalizing proneness, and related brain mechanisms, as distinct processes underlying the expression of psychopathic traits.


Assuntos
Transtorno da Personalidade Antissocial/fisiopatologia , Condicionamento Clássico/fisiologia , Potenciais Evocados/fisiologia , Medo/fisiologia , Inibição Psicológica , Testes Neuropsicológicos , Desempenho Psicomotor/fisiologia , Adolescente , Adulto , Eletroencefalografia , Potenciais Evocados P300/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Adulto Jovem
10.
Psychol Assess ; 32(3): e1-e14, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31944794

RESUMO

The Triarchic Measure of Psychopathy (TriPM) was developed to assess manifest expressions of biobehavioural liabilities relevant to psychopathy and other forms of mental illness. Psychometric findings have been examined for a number of international translations of the TriPM, but further work is needed to evaluate its cross-cultural applicability and its properties in clinical versus nonclinical samples. The present study sought to evaluate the reliability and criterion-related validity and characterize the internal factor structure of the European Portuguese version of the TriPM in a large community sample (N = 1,833), and examine its ability to differentiate between community and prisoner (N = 240) samples. Reliability and criterion-related validity analysis supported the TriPM as an effective measure of psychopathic traits. Internal structure was characterized using exploratory structural equation modeling to specify bifactor models for the TriPM's three subscales and for the inventory as a whole; the model for each subscale included a general factor and a variable number of specific factors as determined by parallel analysis. These modeling analyses demonstrated unidimensionality for each TriPM subscale, and provided support for the triarchic structure of the TriPM as a whole. Additionally, Receiver Operating Characteristics analysis showed that the disinhibition score, as assessed by the TriPM, is the most sensitive for differentiating between prisoner and community samples. Our results are in line with other reports regarding the psychometric properties of the TriPM and provide further evidence for the construct validity of the TriPM. (PsycINFO Database Record (c) 2020 APA, all rights reserved).


Assuntos
Transtorno da Personalidade Antissocial/diagnóstico , Prisioneiros/psicologia , Adolescente , Adulto , Idoso , Transtorno da Personalidade Antissocial/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Psicológicos , Portugal , Escalas de Graduação Psiquiátrica , Psicometria , Curva ROC , Reprodutibilidade dos Testes , Traduções , Adulto Jovem
11.
Behav Brain Sci ; 42: e135, 2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31407984

RESUMO

With respect to De Dreu and Gross's article, we comment on the psychological functions for attack and defense, focusing on associations between individual differences in psychopathic personality traits and the behavioral patterns observed in attack-defense conflicts. We highlight the dimensional nature of psychopathy and formulate hypothetical associations between distinct traits, their different behavioral outcomes, and associated brain mechanisms.


Assuntos
Transtorno da Personalidade Antissocial , Encéfalo , Cognição , Humanos
12.
Exp Psychol ; 66(6): 414-422, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32054428

RESUMO

Participants (N = 119) played the "Dictator Game" (computer mediated) with two bogus computer-simulated players, one of whom, the Dictator, distributed money across ten trials, either as extremely unfair (Inflexible Dictator) or being less unfair (Flexible Dictator). The other player either protested against (Protest condition) or did not react (Apathy condition) to the dictator's decision, after each trial. We measured participants' self-reported anger and disinterest, physiological skin conductance (SCL), heart rate (HR), and number and type of comments directed to the Dictator. Anger and number of comments were lower in the Apathy than in the Protest condition. Participants' SCL, HR, and protest comments decreased in the Apathy condition, and increased in the Protest condition. Protest assumed a more punitive tone in the Inflexible than in the Flexible Dictator condition. We discuss these results' contribution to understand individuals' motivation to engage in protest and apathy, and the role of emotions in that process.


Assuntos
Ira/fisiologia , Simulação por Computador/normas , Emoções/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
13.
Front Psychiatry ; 9: 317, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30104985

RESUMO

Background: Studies on Contemplative Landscapes (CL) show that not only do they have high ecological and visual values and are preferred by a majority of people, but they also can be beneficial to our mental health and well-being. Physical attributes of CL have been studied and operationalized, which has led to the development of the psychometric measurement tool called the Contemplative Landscape Questionnaire (CLQ) (1). Objectives: In the present study, we applied an experimental approach to the analysis of CL. We hypothesized that, when compared to Non-Contemplative Landscapes (NCL), they would induce higher frontal alpha power asymmetry, higher temporal beta power asymmetry and lower bilateral frontal beta power. Methods: Thirty-two healthy individuals (12 female) took part in the study. During the experimental protocol, participants were asked to passively view 12 landscapes, six CL and six NCL, while continuous EEG was recorded in a within-subjects design. Results: We found significantly increased power in the beta frequency band of the right temporal brain regions in the viewings of CL compared to NCL Conclusions: The findings suggest that Contemplative Landscapes capture more visual, stimuli-driven attention from the viewers and can be linked with switching attention systems (described in Attention Restoration Theory), which is compatible with a stress reduction mechanism.

14.
J Neurosci Methods ; 267: 126-31, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27091368

RESUMO

BACKGROUND: The EEG technique has decades of valid applications in clinical and experimental neurophysiology. EEG equipment and data analysis methods have been characterized by remarkable developments, but the skin-to-electrode signal transfer remains a challenge for EEG recording. NEW METHOD: A novel quasi-dry system - the polymer wick-based electrode - was developed to overcome the limitations of conventional dry and wet silver/silver-chloride (Ag/AgCl) electrodes for EEG recording. RESULTS: Nine participants completed an auditory oddball protocol with simultaneous EEG acquisition using both the conventional Ag/AgCl and the wick electrodes. Wick system successfully recorded the expected P300 modulation. COMPARISON WITH EXISTING METHOD(S): Standard ERP analysis, residual random noise analysis, and single-trial analysis of the P300 wave were performed in order to compare signal acquired by both electrodes. It was found that the novel wick electrode performed similarly to the conventional Ag/AgCl electrodes. CONCLUSIONS: The developed wick electrode appears to be a reliable alternative for EEG research, representing a promising halfway alternative between wet and dry electrodes.


Assuntos
Eletrodos , Eletroencefalografia/instrumentação , Adulto , Artefatos , Percepção Auditiva/fisiologia , Encéfalo/fisiologia , Desenho de Equipamento , Potenciais Evocados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Polímeros , Reprodutibilidade dos Testes
15.
Clin Neurophysiol ; 127(1): 499-508, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26154993

RESUMO

OBJECTIVE: The literature suggests that the N1 and P2 waves of the auditory ERP are dissociable at the developmental, experimental, and source levels. At the experimental level, inconsistent findings suggest different effects of intensity on the amplitudes of the auditory N1 and P2. Our main goal was to analyze the intensity dependence of the auditory N1 and P2 while controlling for habituation effects. METHODS: We examined the intensity dependence of both averaged and single-trial auditory N1 and P2 waves elicited in a repeated-stimulation protocol. RESULTS: N1 and P2 revealed similar intensity dependence on both standard and filter denoised ERP, with a linear tendency for higher intensities to elicit higher absolute peak amplitudes. At the single-trial level, both waves covary irrespective of stimulus intensity and trial order. CONCLUSIONS: Our results suggest that stimulus intensity variation induces similar effects on both and N1 and P2 and partially contradict previous data that classified the P2 as a non-habituating component. SIGNIFICANCE: Our findings contribute to the ongoing discussion on the functional significance of the auditory P2 deflection. In addition, the present work demonstrated the applicability of a filter denoising method for single-trial estimation in the analysis of the experimental effects on auditory ERP components.


Assuntos
Estimulação Acústica/métodos , Eletroencefalografia/métodos , Potenciais Evocados Auditivos/fisiologia , Som , Adulto , Feminino , Humanos , Masculino , Tempo de Reação/fisiologia , Adulto Jovem
16.
Int J Psychophysiol ; 99: 48-56, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26659012

RESUMO

Findings concerning the emotional modulation of the N170 component of the visual event-related potential are mixed. In the present report we tested the hypothesis that the emotional modulation of the N170 may be driven by the perceived emotional arousal of the stimuli, rather than by specific emotional categories. Fifty-four participants viewed facial expressions of anger, disgust, fear and happiness, plus low arousal neutral faces. All emotional categories were matched in arousal, while stimuli within each category varied parametrically in this dimension. The modulation of the electrocortical activity on the N170 time-window was analyzed in the time domain and via time-frequency decomposition. The effects of emotion and arousal were analyzed separately. In the time domain N170 amplitudes co-varied parametrically with perceived arousal, regardless of emotional category. This modulation was linearly associated with the power of the theta, alpha, and beta frequency bands. Moreover, fear was associated with a trend for increased N170 amplitudes, enhanced alpha power, and increased broad band inter-trial phase coherence. These results support the views that a) the activity in N170 time window is fundamentally modulated by perceived arousal, b) the modulation of the N170 may be the product of an increased evoked response, rather than the result of phase resetting processes, and c) facial expressions of fear retain some processing primacy, that may be related to their increased value as environmental cues.


Assuntos
Nível de Alerta/fisiologia , Emoções/fisiologia , Potenciais Evocados Visuais/fisiologia , Expressão Facial , Estimulação Luminosa/métodos , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
17.
Int J Psychophysiol ; 94(3): 311-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25304172

RESUMO

The N1 and P2 components of the event-related potential are relevant markers in the processing of auditory information, indicating the presence of several acoustic phenomena, such as pure tones or speech sounds. In addition, the expression of these components seems to be sensitive to diverse experimental variations. The main purpose of the present investigation was to explore the role of inter-stimulus interval (ISI) on the N1 and P2 responses, considering two widely used experimental paradigms: a single tone task (1000 Hz sound repeated in a fixed rhythm) and an auditory oddball (80% of the stimuli were equal to the sound used in the single tone and the remaining were a 1500 Hz tone). Both tasks had four different conditions, and each one tested a fixed value of ISI (600, 1000, 3000, or 6000 ms). A sample of 22 participants performed these tasks, while an EEG was recorded, in order to examine the maximum amplitude of the N1 and P2 components. Analysis of the stimuli in the single tone task and the frequent tones in the oddball task revealed a similar outcome for both tasks and for both components: N1 and P2 amplitudes were enhanced in conditions with longer ISIs regardless of task. This response pattern emphasizes the dependence of both the N1 and P2 components on the ISI, especially in a scenario of repetitive and regular stimulation. The absence of task effects suggests that the ISI effect reported may depend on refractory mechanisms rather than being due to habituation effects.


Assuntos
Estimulação Acústica/métodos , Potenciais Evocados Auditivos/fisiologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Adulto , Potenciais Evocados/fisiologia , Feminino , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
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