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1.
J Exp Psychol Hum Percept Perform ; 50(3): 280-294, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38421775

RESUMO

Humans use selective attention to prioritize visual features, like color or shape, as well as discrete spatial locations, and these effects are sensitive to the experience of reward. Reward-associated features and locations are accordingly prioritized from early in the visual hierarchy. Attention is also sensitive to the establishment of visual objects: selection of one constituent object part often leads to prioritization of other locations on that object. But very little is known about the influence of reward on this object-based control of attention. Here we show in four experiments that reward prioritization and object prioritization interact in visual cognition to guide selection. Experiment 1 establishes groundwork for this investigation, showing that reward feedback does not negate object prioritization. In Experiment 2, we corroborate the hypothesis that reward prioritization and object prioritization emerge concurrently. In Experiment 3, we find that reward prioritization and object prioritization sustain and interact in extinction, when reward feedback is discontinued. We verify this interaction in Experiment 4, linking it to task experience rather than the strategic utility of the reward association. Results suggest that information gathered from locations on reward-associated objects gains preferential access to cognition. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Cognição , Percepção Visual , Humanos , Recompensa
2.
Acta Psychol (Amst) ; 231: 103793, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36402087

RESUMO

Direct verbal suggestibility refers to the capacity for an individual to experience perceptual, motor, affective and cognitive changes in response to verbal suggestions. Suggestibility is characterized by pronounced, yet reliable, inter-individual differences. Previous research and theoretical considerations suggest that greater impulsivity and compulsivity is associated to higher suggestibility, but the characteristics and mediating factors of this association are poorly understood. Using established psychometric measures in an online sample, we found positive correlations between the domain comprising impulsivity, compulsivity and behavioural activation, and the domain of suggestibility, dissociation and absorption. We also observed that dissociation and absorption mediated the link between suggestibility and impulsivity, and between suggestibility and behavioural activation, respectively. These results confirm the positive link between suggestibility and the impulsivity/compulsivity domain and shed new light on the characterisation of traits associated with suggestibility.


Assuntos
Comportamento Impulsivo , Sugestão , Humanos , Comportamento Impulsivo/fisiologia
3.
Neuroimage ; 251: 119005, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35176493

RESUMO

When reading a sentence, individual words can be combined to create more complex meaning. In this study, we sought to uncover brain regions that reflect the representation of the meaning of sentences at the topic level, as opposed to the meaning of their individual constituent words when considered irrespective of their context. Using fMRI, we recorded the neural activity of participants while reading sentences. We constructed a topic-level sentence representations using the final layer of a convolutional neural network (CNN) trained to classify Wikipedia sentences into broad semantic categories. This model was contrasted with word-level sentence representations constructed using the average of the word embeddings constituting the sentence. Using representational similarity analysis, we found that the medial prefrontal cortex, lateral anterior temporal lobe, precuneus, and angular gyrus more strongly represent sentence topic-level, compared to word-level, meaning, uncovering the important role of these semantic system regions in the representation of topic-level meaning. Results were comparable when sentence meaning was modelled with a multilayer perceptron that was not sensitive to word order within a sentence, suggesting that the learning objective, in the terms of the topic being modelled, is the critical factor in capturing these neural representational spaces.


Assuntos
Idioma , Lobo Temporal , Mapeamento Encefálico , Humanos , Imageamento por Ressonância Magnética , Redes Neurais de Computação , Lobo Parietal , Córtex Pré-Frontal/diagnóstico por imagem , Semântica , Lobo Temporal/diagnóstico por imagem
4.
Am J Clin Hypn ; 63(4): 355-371, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33999774

RESUMO

A diverse array of studies has been devoted to understanding the neurochemical systems supporting responsiveness to hypnotic suggestions, with implications for experimental and clinical applications of hypnosis. However, this body of research has only rarely been integrated and critically evaluated and the prospects for the reliable pharmacological manipulation of hypnotic suggestibility remain poorly understood. Here we draw on pharmacological, genotyping, neuroimaging, and electrophysiological research to synthesize current knowledge regarding the potential role of multiple widely-studied neurochemicals in response to suggestion. Although we reveal multiple limitations with this body of evidence, we identify converging results implicating different neurochemical systems in response to hypnotic suggestion. We conclude by assessing the extent to which different results align or diverge and outline multiple avenues for future research. Elucidating the neurochemical systems underlying response to suggestion has the potential to significantly advance our understanding of suggestion.


Assuntos
Hipnose , Neuroquímica , Humanos , Hipnóticos e Sedativos , Sugestão
5.
Int J Clin Exp Hypn ; 69(1): 50-71, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33513059

RESUMO

The most well-established finding gleaned from decades of experimental hypnosis research is that individuals display marked variability in responsiveness to hypnotic suggestions. Insofar as this variability impacts both treatment outcome in therapeutic applications of hypnosis as well as responsiveness to suggestions in experimental contexts, it is imperative that clinicians and researchers use robust measures of hypnotic suggestibility. The current paper critically evaluates contemporary measures of hypnotic suggestibility. After reviewing the most widely used measures, we identify multiple properties of these instruments that result in the loss of valuable information, including binary scoring and single-trial sampling, and hinder their utility, such as the inclusion of suboptimal suggestion content. The scales are not well-suited for contemporary research questions and have outlived their usefulness. We conclude by outlining ways in which the measurement of hypnotic suggestibility can be advanced.


Assuntos
Sugestão , Pesquisa Comportamental/métodos , Pesquisa Comportamental/normas , Humanos
6.
J Neurosci ; 40(49): 9476-9486, 2020 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-33115930

RESUMO

Experience seems continuous and detailed despite saccadic eye movements changing retinal input several times per second. There is debate whether neural signals related to updating across saccades contain information about stimulus features, or only location pointers without visual details. We investigated the time course of low-level visual information processing across saccades by decoding the spatial frequency of a stationary stimulus that changed from one visual hemifield to the other because of a horizontal saccadic eye movement. We recorded magnetoencephalography while human subjects (both sexes) monitored the orientation of a grating stimulus, making spatial frequency task irrelevant. Separate trials, in which subjects maintained fixation, were used to train a classifier, whose performance was then tested on saccade trials. Decoding performance showed that spatial frequency information of the presaccadic stimulus remained present for ∼200 ms after the saccade, transcending retinotopic specificity. Postsaccadic information ramped up rapidly after saccade offset. There was an overlap of over 100 ms during which decoding was significant from both presaccadic and postsaccadic processing areas. This suggests that the apparent richness of perception across saccades may be supported by the continuous availability of low-level information with a "soft handoff" of information during the initial processing sweep of the new fixation.SIGNIFICANCE STATEMENT Saccades create frequent discontinuities in visual input, yet perception appears stable and continuous. How is this discontinuous input processed resulting in visual stability? Previous studies have focused on presaccadic remapping. Here we examined the time course of processing of low-level visual information (spatial frequency) across saccades with magnetoencephalography. The results suggest that spatial frequency information is not predictively remapped but also is not discarded. Instead, they suggest a soft handoff over time between different visual areas, making this information continuously available across the saccade. Information about the presaccadic stimulus remains available, while the information about the postsaccadic stimulus has also become available. The simultaneous availability of both the presaccadic and postsaccadic information could enable rich and continuous perception across saccades.


Assuntos
Movimentos Sacádicos/fisiologia , Córtex Visual/fisiologia , Percepção Visual/fisiologia , Adulto , Potenciais Evocados/fisiologia , Feminino , Fixação Ocular , Humanos , Magnetoencefalografia , Masculino , Processos Mentais/fisiologia , Orientação , Estimulação Luminosa , Desempenho Psicomotor , Percepção Espacial , Campos Visuais , Adulto Jovem
9.
J Neurosci Methods ; 209(1): 212-8, 2012 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-22743800

RESUMO

The event-related potential (ERP) and event-related field (ERF) techniques provide valuable insights into the time course of processes in the brain. Because neural signals are typically weak, researchers commonly filter the data to increase the signal-to-noise ratio. However, filtering may distort the data, leading to false results. Using our own EEG data, we show that acausal high-pass filtering can generate a systematic bias easily leading to misinterpretations of neural activity. In particular, we show that the early ERP component C1 is very sensitive to such effects. Moreover, we found that about half of the papers reporting modulations in the C1 range used a high-pass digital filter cut-off above the recommended maximum of 0.1 Hz. More generally, among 185 relevant ERP/ERF publications, 80 used cutoffs above 0.1 Hz. As a consequence, part of the ERP/ERF literature may need to be re-analyzed. We provide guidelines on how to minimize filtering artifacts.


Assuntos
Artefatos , Processamento de Sinais Assistido por Computador , Eletroencefalografia , Potenciais Evocados , Humanos
10.
Emotion ; 11(5): 1134-43, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21787079

RESUMO

It has been shown that attention is drawn toward emotional stimuli. In particular, eye movement research suggests that gaze is attracted toward emotional stimuli in an unconscious, automated manner. We addressed whether this effect remains when emotional targets are embedded within complex real-world scenes. Eye movements were recorded while participants memorized natural images. Each image contained an item that was either neutral, such as a bag, or emotional, such as a snake or a couple hugging. We found no latency difference for the first target fixation between the emotional and neutral conditions, suggesting no extrafoveal "pop-out" effect of emotional targets. However, once detected, emotional targets held attention for a longer time than neutral targets. The failure of emotional items to attract attention seems to contradict previous eye-movement research using emotional stimuli. However, our results are consistent with studies examining semantic drive of overt attention in natural scenes. Interpretations of the results in terms of perceptual and attentional load are provided.


Assuntos
Emoções , Natureza , Percepção Visual , Atenção , Movimentos Oculares , Feminino , Fixação Ocular , Humanos , Masculino , Estimulação Luminosa , Fatores de Tempo
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