Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
JMIR Res Protoc ; 8(5): e12061, 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31094340

RESUMO

BACKGROUND: Philip Morris International (PMI) has developed a novel heat-not-burn tobacco product, Tobacco Heating System (THS), which is marketed under the brand name of IQOS with HEETS (IQOS). The aerosol generated by THS has substantially fewer toxicants than combustible cigarette smoke, although the extent of the reduction of harmful and potentially harmful constituents reported varies between studies. To evaluate the potential harm reduction associated with IQOS use, the assessment of the uptake and continued use of IQOS in the context of all other tobacco- and nicotine-containing products is crucial. In March 2018, PMI launched cross-sectional surveys in Germany, Italy, and the United Kingdom (Greater London) to estimate the prevalence and use patterns of IQOS and other tobacco- and nicotine-containing products use in these 3 markets following the commercialization of IQOS. This study describes the protocol of the surveys. OBJECTIVE: The objectives of these surveys are to estimate the prevalence of tobacco- and nicotine-containing products use; describe past and current patterns of use; and explore their associations with self-reported health, motivation to use, risk perceptions, and perceived aesthetic changes. METHODS: The overall design of the surveys is similar in all 3 countries. Repeated cross-sectional surveys are being conducted annually over 3 consecutive years (2018 to 2020) and in 2 samples: a representative sample of the general population and a sample of IQOS users. A total of 6085 adults per year will be selected from the general population for each survey through multistage stratified sampling, and participants will respond to face-to-face computer-assisted personal interviews. In addition, 1404, 1384, and 1246 IQOS users per year in Germany, Italy, and Greater London, respectively, will be randomly selected from the PMI IQOS user database and will be invited to complete the Web-based survey using computer-assisted self-interviews. The Smoking Questionnaire is used to assess the tobacco use patterns of the participants. RESULTS: The recruitment of the general population sample began in March 2018 and that of the IQOS user sample began in April 2018. The data collection is ongoing, and the results of the first year data analysis are expected to be available by June 2019. CONCLUSIONS: As the design of the 3 surveys is similar, the results will allow for cross-countries comparison of the prevalence of IQOS and other tobacco- and nicotine-containing products use as well as patterns of use and associated factors. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/12061.

2.
Front Neurosci ; 7: 209, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24294190

RESUMO

The feedback-related negativity (FRN) is a mid-frontal event-related potential (ERP) recorded in various cognitive tasks and associated with the onset of sensory feedback signaling decision outcome. Some properties of the FRN are still debated, notably its sensitivity to positive and negative reward prediction error (RPE)-i.e., the discrepancy between the expectation and the actual occurrence of a particular feedback,-and its role in triggering the post-feedback adjustment. In the present study we tested whether the FRN is modulated by both positive and negative RPE. We also tested whether an instruction cue indicating the need for behavioral adjustment elicited the FRN. We asked 12 human subjects to perform a problem-solving task where they had to search by trial and error which of five visual targets, presented on a screen, was associated with a correct feedback. After exploration and discovery of the correct target, subjects could repeat their correct choice until the onset of a visual signal to change (SC) indicative of a new search. Analyses showed that the FRN was modulated by both negative and positive prediction error (RPE). Finally, we found that the SC elicited an FRN-like potential on the frontal midline electrodes that was not modulated by the probability of that event. Collectively, these results suggest the FRN may reflect a mechanism that evaluates any event (outcome, instruction cue) signaling the need to engage adaptive actions.

3.
J Neurosci ; 31(42): 15048-52, 2011 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-22016538

RESUMO

Adaptive decision making involves selecting the most valuable option, typically by taking an action. Such choices require value comparisons, but there is debate about whether these comparisons occur at the level of stimuli (goods-based) value, action-based value, or both. One view is that value processes occur in series, with stimulus value informing action value. However, lesion work in nonhuman primates suggests that these two kinds of choice are dissociable. Here, we examined action-value and stimulus-value learning in humans with focal frontal lobe damage. Orbitofrontal damage disrupted the ability to sustain the correct choice of stimulus, but not of action, after positive feedback, while damage centered on dorsal anterior cingulate cortex led to the opposite deficit. These findings argue that there are distinct, domain-specific mechanisms by which outcome value is applied to guide subsequent decisions, depending on whether the choice is between stimuli or between actions.


Assuntos
Lesões Encefálicas/patologia , Lobo Frontal/fisiopatologia , Giro do Cíngulo/fisiopatologia , Aprendizagem Baseada em Problemas , Adulto , Idoso , Análise de Variância , Mapeamento Encefálico , Estudos de Casos e Controles , Comportamento de Escolha/fisiologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Recompensa
4.
J Neurosci ; 31(20): 7527-32, 2011 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-21593337

RESUMO

Recent work in neuroeconomics has shown that regions in orbitofrontal and medial prefrontal cortex encode the subjective value of different options during choice. However, these electrophysiological and neuroimaging studies cannot demonstrate whether such signals are necessary for value-maximizing choices. Here we used a paradigm developed in experimental economics to empirically measure and quantify violations of utility theory in humans with damage to the ventromedial frontal lobe (VMF). We show that people with such damage are more likely to make choices that violate the generalized axiom of revealed preference, which is the one necessary and sufficient condition for choices to be consistent with value maximization. These results demonstrate that the VMF plays a critical role in value-maximizing choice.


Assuntos
Lesões Encefálicas/patologia , Comportamento de Escolha/fisiologia , Tomada de Decisões/fisiologia , Lobo Frontal/patologia , Lobo Frontal/fisiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa/métodos , Desempenho Psicomotor/fisiologia
5.
Cogn Affect Behav Neurosci ; 10(3): 406-13, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20805541

RESUMO

Disruption of normal emotional experience is central to the phenomenology of depression. Twenty-three depressed outpatients and 23 control subjects performed a computerized decision-making task, during which affective ratings were assessed online to identify various dimensions of emotional experience. We sought to contrast regret (the comparison of the outcomes of selected and nonselected options) with the general negative appraisal of task events. The experience of regret was reduced in depressed patients, an effect that was particularly related to self-reported apathy scores. In an exploratory analysis, we observed that females had a general downward shift in their ratings, as compared with males, but disappointment and regret effects were of similar magnitude. The possible contribution of the orbitofrontal cortex to the phenomenology of regret is discussed. Supplemental materials for this article may be downloaded from http://cabn.psychonomic-journals.org/content/supplemental.


Assuntos
Afeto , Apatia , Tomada de Decisões , Transtorno Depressivo/psicologia , Reforço Psicológico , Análise de Variância , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Análise por Pareamento , Projetos Piloto , Valores de Referência , Autoavaliação (Psicologia) , Enquadramento Psicológico , Fatores Sexuais
6.
Science ; 304(5674): 1167-70, 2004 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-15155951

RESUMO

Facing the consequence of a decision we made can trigger emotions like satisfaction, relief, or regret, which reflect our assessment of what was gained as compared to what would have been gained by making a different decision. These emotions are mediated by a cognitive process known as counterfactual thinking. By manipulating a simple gambling task, we characterized a subject's choices in terms of their anticipated and actual emotional impact. Normal subjects reported emotional responses consistent with counterfactual thinking; they chose to minimize future regret and learned from their emotional experience. Patients with orbitofrontal cortical lesions, however, did not report regret or anticipate negative consequences of their choices. The orbitofrontal cortex has a fundamental role in mediating the experience of regret.


Assuntos
Emoções , Lobo Frontal/fisiologia , Pensamento , Adulto , Encefalopatias/fisiopatologia , Encefalopatias/psicologia , Comportamento de Escolha , Tomada de Decisões , Retroalimentação Psicológica , Feminino , Resposta Galvânica da Pele , Jogo de Azar , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Psicológicos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...