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1.
Conscious Cogn ; 115: 103568, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37708623

RESUMO

To investigate whether local elements are grouped into global shapes in the absence of awareness, we introduced two different masked priming designs (e.g., the classic dissociation paradigm and a trial-wise probe and prime discrimination task) and collected both objective (i.e., performance based) and subjective (using the perceptual awareness scale [PAS]) awareness measures. Prime visibility was manipulated using three different prime-mask stimulus onset asynchronies (SOAs) and an unmasked condition. Our results showed that assessing prime visibility trial-wise heavily interfered with masked priming preventing any prime facilitation effect. The implementation of Bayesian regression models, which predict priming effects for participants whose awareness levels are at chance level, provided strong evidence in favor of the hypothesis that local elements group into global shape in the absence of awareness for SOAs longer than 50 ms, suggesting that prime-mask SOA is a crucial factor in the processing of the global shape without awareness.


Assuntos
Mascaramento Perceptivo , Humanos , Tempo de Reação , Teorema de Bayes
2.
Behav Res Methods ; 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37749425

RESUMO

In recent years, assumptions about the existence of a single construct of happiness that accounts for all positive emotions have been questioned. Instead, several discrete positive emotions with their own neurobiological and psychological mechanisms have been proposed. Of note, the effects of positive emotions on language processing are not yet properly understood. Here we provide a database for a large set of 9000 Spanish words scored by 3437 participants in the positive emotions of awe, contentment, amusement, excitement, serenity, relief, and pleasure. We also report significant correlations between discrete positive emotions and several affective (e.g., valence, arousal, happiness, negative discrete emotions) and lexico-semantic (e.g., frequency of use, familiarity, concreteness, age of acquisition) characteristics of words. Finally, we analyze differences between words conveying a single emotion ("pure" emotion words) and those denoting more than one emotion ("mixed" emotion words). This study will provide researchers a rich source of information to do research that contributes to expanding the current knowledge on the role of positive emotions in language. The norms are available at https://doi.org/10.6084/m9.figshare.21533571.v2.

3.
J Cogn Neurosci ; 33(7): 1295-1310, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34496396

RESUMO

The level of processing hypothesis (LoP) proposes that the transition from unaware to aware visual perception is graded for low-level (i.e., energy, features) stimulus whereas dichotomous for high-level (i.e., letters, words, meaning) stimulus. In this study, we explore the behavioral patterns and neural correlates associated with different depths (i.e., low vs. high) of stimulus processing. The low-level stimulus condition consisted of identifying the color (i.e., blue/blueish vs. red/reddish) of the target, and the high-level stimulus condition consisted of identifying stimulus category (animal vs. object). Behavioral results showed that the levels of processing manipulation produced significant differences in both the awareness rating distributions and accuracy performances between tasks, the low-level task producing more intermediate subjective ratings and linearly increasing accuracy performances and the high-level task producing less intermediate ratings and a more nonlinear pattern for accuracies. The electrophysiological recordings revealed two correlates of visual awareness, an enhanced posterior negativity in the N200 time window (visual awareness negativity [VAN]), and an enhanced positivity in the P3 time window (late positivity [LP]). The analyses showed a double dissociation between awareness and the level of processing hypothesis manipulation: Awareness modulated VAN amplitudes only in the low-level color task, whereas LP amplitude modulations were observed only in the higher level category task. These findings are compatible with a two-stage microgenesis model of conscious perception, where an early elementary phenomenal sensation of the stimulus (i.e., the subjective perception of color) would be indexed by VAN, whereas stimulus' higher level properties (i.e., the category of the target) would be reflected in the LP in a later latency range.


Assuntos
Conscientização , Potenciais Evocados , Estado de Consciência , Eletroencefalografia , Percepção Visual
4.
Conscious Cogn ; 85: 103022, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32950722

RESUMO

Does a visual percept emerge to consciousness in a graded manner (i.e. evolving through increasing degrees of clarity), or according to a dichotomous, "all-or-none" pattern (i.e. abruptly transitioning from unawareness to awareness)? The level of processing hypothesis (LoP; B. Windey and A. Cleeremans, 2015) recently proposed a theoretical framework where the transition from unaware to aware visual experience is graded for low-level stimulus representations (i.e. stimulus "energy" or "feature" levels) whereas it is dichotomous for high-level (i.e. the perception of "letters", "words" or "meaning") stimulus perception. Here, we will critically review current behavioral and brain-based evidence on the LoP hypothesis and discuss potential challenges (such as differences in LoP conceptualizations, awareness scale related issues, attentional confounds and divergences on experimental factors or statistical analyses) which might be of use for future research within the field. Overall, the LoP hypothesis is a recent and promising proposal that attempts to integrate divergent evidence on the graded vs. dichotomous emergence of awareness debate. Whereas current evidence validates some of the assumptions proposed by the LoP account, there is still much work to do on both methodological and experimental levels. Future neuroimaging studies might help to disentangle the current complex pattern of results found in LoP studies and, importantly, shed some light on the ongoing debate about the search for the Neural Correlates of Consciousness (NCC).


Assuntos
Conscientização , Percepção Visual , Encéfalo , Estado de Consciência , Humanos
5.
Dement Geriatr Cogn Disord ; 43(1-2): 59-70, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28013307

RESUMO

BACKGROUND/AIMS: Category fluency tasks have been widely used to assess cognitive functioning in both clinical and experimental environments as an index of cognitive and psycholinguistic dysfunctions in dementia. Typically, a reduced group of semantic categories has been selected for neuropsychological assessment (e.g., animals, fruits or vegetables), although empirical support for the prevalence of one category among others is absent in the literature. METHODS: We provide an empirical evaluation of the ability of 14 category fluency tasks to discriminate between subjects with dementia of the Alzheimer type and healthy elderly participants. As a novelty, we used both receiver operating characteristic (ROC) curves and quality ROC calibrated analyses to characterize the interplay of sensitivity and specificity of every category fluency task performance as a screening tool. The use of calibrated measures provided us with a useful tool for comparing the diagnostic ability of the different categories, as well as making rankings of categories based on the quality indices of efficiency, sensitivity, and specificity. RESULTS: The habitually used category of animals is far from being the most efficient one in terms of its diagnostic power to evaluate dementia. CONCLUSION: Our study might guide the selection of suitable category fluency tasks according to the diagnostic purposes in dementia.


Assuntos
Cognição/fisiologia , Demência/diagnóstico , Demência/psicologia , Testes Neuropsicológicos , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/psicologia , Animais , Área Sob a Curva , Calibragem , Manual Diagnóstico e Estatístico de Transtornos Mentais , Escolaridade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Sensibilidade e Especificidade
6.
Conscious Cogn ; 53: 31-46, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28618282

RESUMO

Previous research on perceptual organization operations still provides contradictory evidence on whether the integration of sparse local elements into coherently unified shapes and the construction of the illusory form are accomplished without the need of awareness. In the present study, three experiments were conducted in which participants were presented with masked (Experiment 1, SOA=27ms; Experiment 2; SOA=53ms) and unmasked (Experiment 3) primes consisting of geometric shapes (a square or a diamond) that could be congruent or incongruent with subsequent probe stimuli (square vs. diamond). Furthermore, the primes were divided into: a grouping condition (where local elements may group together into global shapes), an illusory condition (where the arrangement of local elements produced illusory shapes) and a hybrid condition (where both operations were presented simultaneously). While no priming effects were found for the shortest SOA (27ms), both grouping and illusory primes produced significant priming effects in the longer SOA (53ms). On the other hand, results in Experiment 3 (unmasked) showed strong priming effects for the grouping of the inducers in both the grouping and the hybrid conditions, and also a significant but weaker priming effect for the illusory condition. Overall, our results support the possibility of the integration of local visual features into a global shape in the absence of awareness and, likewise, they suggest an early -subliminal- construction of the illusory shape, implying that feedback projections from higher to lower visual areas are not crucial in the construction of the illusory form.


Assuntos
Conscientização/fisiologia , Percepção de Forma/fisiologia , Ilusões Ópticas/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Mascaramento Perceptivo/fisiologia , Priming de Repetição/fisiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Subliminar , Adulto Jovem
7.
Neurocase ; 22(5): 426-435, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27493013

RESUMO

This study adapted a new task to assess visuospatial and verbal working memory impairments in patients with Alzheimer Disease (AD), including an executive strategy of information suppression. The aim was to examine the visuospatial and verbal difficulties, and additionally to explore the average sex differences, during a 2-year follow-up study. The results indicated that patients with AD showed a significantly lower performance, compared with healthy elderly controls, especially with the suppression of information required in this new task. However, suppression did not lead to a significantly greater decline in the performance of patients when compared with the control group.


Assuntos
Doença de Alzheimer/complicações , Transtornos da Memória/etiologia , Memória de Curto Prazo/fisiologia , Transtornos da Percepção/etiologia , Processamento Espacial/fisiologia , Aprendizagem Verbal/fisiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Estudos Longitudinais , Masculino , Entrevista Psiquiátrica Padronizada , Testes Neuropsicológicos , Estimulação Luminosa , Estatísticas não Paramétricas
8.
Conscious Cogn ; 25: 1-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24518805

RESUMO

Previous studies making use of indirect processing measures have shown that perceptual grouping can occur outside the focus of attention. However, no previous study has examined the possibility of subliminal processing of perceptual grouping. The present work steps forward in the study of perceptual organization, reporting direct evidence of subliminal processing of Gestalt patterns. In two masked priming experiments, Gestalt patterns grouped by proximity or similarity that induced either a horizontal or vertical global orientation of the stimuli were presented as masked primes and followed by visible targets that could be congruent or incongruent with the orientation of the primes. The results showed a reliable priming effect in the complete absence of prime awareness for both proximity and similarity grouping principles. These findings suggest that a phenomenal report of the Gestalt pattern is not mandatory to observe an effect on the response based on the global properties of Gestalt stimuli.


Assuntos
Teoria Gestáltica , Mascaramento Perceptivo/fisiologia , Estimulação Subliminar , Inconsciente Psicológico , Percepção Visual/fisiologia , Adulto , Discriminação Psicológica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reconhecimento Visual de Modelos/fisiologia , Desempenho Psicomotor , Tempo de Reação , Percepção Espacial/fisiologia , Adulto Jovem
9.
Cogn Process ; 15(3): 253-67, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24866175

RESUMO

Several experimental studies have shown that there exists an association between emotion words and the vertical spatial axis. However, the specific conditions under which this conceptual-physical interaction emerges are still unknown, and no study has been devised to test whether longer linguistic units than words can lead to a mapping of emotions on vertical space. In Experiment 1, Spanish and Colombian participants performed a representative verbal emotional contexts production task (RVEC task) requiring participants to produce RVEC for the emotions of joy, sadness, surprise, anger, fear, and disgust. The results showed gender and cultural differences regarding the average number of RVEC produced. The most representative contexts of joy and sadness obtained in Experiment 1 were used in Experiment 2 in a novel spatial-emotional congruency verification task (SECV task). After reading a sentence, the participants had to judge whether a probe word, displayed in either a high or low position on the screen, was congruent or incongruent with the previous sentence. The question was whether the emotion induced by the sentence could modulate the responses to the probes as a function of their position in a vertical axis by means of a metaphorical conceptual-spatial association. Overall, the results indicate that a mapping of emotions on vertical space can occur for linguistic units larger than words, but only when the task demands an explicit affective evaluation of the target.


Assuntos
Emoções/fisiologia , Percepção Espacial/fisiologia , Comportamento Verbal/fisiologia , Vocabulário , Adolescente , Adulto , Análise de Variância , Comparação Transcultural , Feminino , Humanos , Julgamento , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa , Psicolinguística , Tempo de Reação/fisiologia , Fatores Sexuais , Adulto Jovem
10.
Behav Res Methods ; 46(4): 1088-97, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24415408

RESUMO

This article presents a new corpus of 820 words pertaining to 14 semantic categories, 7 natural (animals, body parts, insects, flowers, fruits, trees, and vegetables) and 7 man-made (buildings, clothing, furniture, kitchen utensils, musical instruments, tools, and vehicles); each word in the database was collected empirically in a previous exemplar generation study. In the present study, 152 Spanish speakers provided data for four psycholinguistic variables known to affect lexical-semantic processing in both neurologically intact and brain-damaged participants: age of acquisition, familiarity, manipulability, and typicality. Furthermore, we collected lexical frequency data derived from Internet search hits, plus three additional Spanish lexical frequency indexes. Word length, number of syllables, and the proportion of respondents citing the exemplar as a category member-which can be useful as an additional measure of typicality-are also provided. Reliability and validity indexes showed that our items display characteristics similar to those of other corpora. Overall, this new corpus of words provides a useful tool for scientists engaged in cognitive- and neuroscience-based research focused on examining language, memory, and object processing. The full set of norms can be downloaded from www.psychonomic.org/archive.


Assuntos
Idioma , Reconhecimento Psicológico/classificação , Semântica , Adulto , Idade de Início , Idoso , Feminino , Humanos , Armazenamento e Recuperação da Informação , Linguística , Estudos Longitudinais , Masculino , Memória , Pessoa de Meia-Idade , Apego ao Objeto , Psicolinguística , Valores de Referência , Reprodutibilidade dos Testes , Espanha , Terminologia como Assunto , Adulto Jovem
11.
J Gen Psychol ; : 1-17, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37906102

RESUMO

The relation between response time and performance in cognitive tasks is increasingly evident. In the present study, we analyzed the effect of participants' spontaneous speed when responding to a mental rotation task. We carried out a data reanalysis from a previous study where a training of 3 practice sessions of 100 trials each was applied. The procedure was applied to a sample of 21 high school students (11 boys, 10 girls). The relation between response time and performance (hits) across the training trials was analyzed. In addition, we carried out a regression analysis of performance on the learning task as a function of response time on that same task, as well as with the score on two previously applied tests of spatial intelligence and fluid intelligence. Results showed, (a) a significant relationship (r = 0.624) between response time and hits, (b) that the group of participants with longer response times performed better; (c) that participants' response time explained most of the variance of their score on the training task in the regression analysis, although spatial and fluid intelligence scores improved the prediction of performance. Our results suggest that the reflective style achieves greater performance in solving spatial tasks, which could have important practical implications to promote a slower and more reflective style when solving school tasks with spatial components.

12.
Atten Percept Psychophys ; 84(3): 771-780, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35359230

RESUMO

In the context of urban life, some monuments are ecologically relevant landmarks for some people. However, previous research on the topic of incidental memory of everyday settings has relatively ignored how people remember monuments from their environments. The present work examined visual memory (i.e., recall and recognition) and metamemory for the Puerta de Alcalá ("Alcalá Gate" in English), a famous ornamental monument in the city of Madrid (Spain). Despite the monument's perceptual simplicity, participants showed poor visual memory of it in a recall task (drawings), as only 16% of them correctly drew the monument; moreover, only 45% of the participants correctly recognized it in a four-alternative forced-choice test. In contrast, participants reported higher levels of confidence for both recall and recognition (51.57 ± 20.5 and 79.54 ± 19.6, respectively on a 100-point scale). Importantly, memory performance did not vary as a function of the number of years lived near the monument or of the self-reported contact frequency (familiarity) with the monument. The current findings have relevant implications in understanding the link between visual attention, memory, and metamemory in real-world settings.


Assuntos
Metacognição , Humanos , Memória , Transtornos da Memória , Rememoração Mental , Reconhecimento Psicológico
13.
Nat Hum Behav ; 6(12): 1731-1742, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36266452

RESUMO

Following theories of emotional embodiment, the facial feedback hypothesis suggests that individuals' subjective experiences of emotion are influenced by their facial expressions. However, evidence for this hypothesis has been mixed. We thus formed a global adversarial collaboration and carried out a preregistered, multicentre study designed to specify and test the conditions that should most reliably produce facial feedback effects. Data from n = 3,878 participants spanning 19 countries indicated that a facial mimicry and voluntary facial action task could both amplify and initiate feelings of happiness. However, evidence of facial feedback effects was less conclusive when facial feedback was manipulated unobtrusively via a pen-in-mouth task.


Assuntos
Emoções , Expressão Facial , Humanos , Retroalimentação , Felicidade , Face
14.
Q J Exp Psychol (Hove) ; 74(10): 1724-1736, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33818202

RESUMO

The integration between Gestalt grouping cues has been a relatively unexplored issue in vision science. The present work introduces an objective indirect method based on the repetition discrimination task to determine the rules that govern the dominance dynamics of the competition between both intrinsic (Experiment 1: proximity vs luminance similarity) and extrinsic grouping cues (Experiment 2: common region vs connectedness) by means of objective measures of grouping (reaction times and accuracy). Prior to the main task, a novel objective equating task was introduced with the aim of equating the grouping strength of the cues for the visuomotor system. The main task included two single conditions with the grouping cues acting alone as well as two competing conditions displaying the grouping factors pitted against one another. Conventional aggregated analyses were combined with individual analysis and both revealed a consistent pattern of processing dominance of: (1) luminance similarity over proximity and (2) common region over connectedness. Interestingly, the individual analyses showed that, despite the heterogeneous responses to the single conditions, the pattern of dominance between cues was robustly homogeneous among the participants in the competing conditions.


Assuntos
Sinais (Psicologia) , Visão Ocular , Objetivos , Humanos , Tempo de Reação
15.
Br J Psychol ; 111(2): 335-356, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-30993675

RESUMO

In two experiments, we explored the nature of the bias observed in the bat/ball problem of the cognitive reflection test (Frederick, 2005, J. Econ. Perspect., 19, 25), how to override it, and its relation to executive functioning. Based on the original bat/ball problem, we designed two additional isomorphic items. In Experiment 1, for four age groups, including 7-, 11-, and 15-year-olds and adults, we determined that the bias is related to the System 1 intervention; the performance in this item was not a matter of mathematical ability and it could be facilitated by changing the order in which the problems were presented. In Experiment 2, we determined that for 15-year-olds, good and bad performances in the item were related to executive functioning, particularly response-distractor inhibition, updating information in working memory, and the regulation of attention; however, subtle differences were identified when the problem was performed in a facilitative context compared with a non-facilitative context. The results indicated that cognitive abilities are a necessary but non-sufficient condition to resolve the problem.


Assuntos
Cognição/fisiologia , Função Executiva/fisiologia , Adolescente , Atenção/fisiologia , Criança , Feminino , Humanos , Masculino , Memória de Curto Prazo/fisiologia , Testes Neuropsicológicos
16.
Neurosci Lett ; 451(3): 261-5, 2009 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-19146925

RESUMO

In a typical flanker task, responses to a central target ("S" or "N") are modulated by whether the flankers are compatible ("SSSSS") or incompatible ("NNSNN"), with increased reaction times and decreased accuracy on incompatible trials. The role of the motor system in response interference under these conditions remains unclear, however. Here we show that transcranial magnetic stimulation (TMS) of the left primary motor cortex modulates the amount of flanker interference depending on the hand used for the response. Left motor TMS delivered at 200ms after the onset of the array increased interference from incompatible flankers ("SSNSS") when the target response was associated with the contralateral motor response (i.e. for "N" responses with the right hand), relative to when responses were to targets using the (left) hand ipsilateral to the site of TMS. Interestingly, under identical conditions, the degree of flanker interference was reduced when the TMS pulse was applied later in time. The analyses of the TMS-induced motor evoked potentials pointed to motor activity varying in the same conditions. We discuss the implications for understanding response interference and the role of the primary motor cortex in response selection.


Assuntos
Atenção/fisiologia , Cognição/fisiologia , Córtex Motor/fisiologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Estimulação Magnética Transcraniana/métodos , Adolescente , Adulto , Atenção/efeitos da radiação , Cognição/efeitos da radiação , Potencial Evocado Motor/fisiologia , Potencial Evocado Motor/efeitos da radiação , Feminino , Lateralidade Funcional/fisiologia , Mãos/inervação , Mãos/fisiologia , Humanos , Masculino , Córtex Motor/anatomia & histologia , Córtex Motor/efeitos da radiação , Movimento/fisiologia , Movimento/efeitos da radiação , Testes Neuropsicológicos , Estimulação Luminosa , Desempenho Psicomotor/efeitos da radiação , Radiação , Tempo de Reação/efeitos da radiação , Adulto Jovem
17.
J Gen Psychol ; 136(4): 407-27, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19943613

RESUMO

Previous studies on the processing of hierarchical patterns (Luna & Montoro, 2008) have shown that altering the spatial relationships between the local elements affected processing dominance by decreasing global advantage. In the present article, the authors examine whether heterogeneity or a sparse distribution of the local elements was the responsible factor for this effect. In Experiments 1 and 2, the distance between the local elements was increased in a similar way, but between-element distance was homogeneous in Experiment 1 and heterogeneous in Experiment 2. In Experiment 3, local elements' size was varied by presenting global patterns composed of similar large or small local elements and of different large and small sizes. The results of the present research showed that, instead of element sparsity, spatial heterogeneity that could change the appearance of the global form as well as the salience of the local elements was the main determiner of impairing global processing.


Assuntos
Atenção , Percepção de Distância , Área de Dependência-Independência , Orientação , Reconhecimento Visual de Modelos , Percepção de Tamanho , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Reação , Adulto Jovem
18.
Atten Percept Psychophys ; 81(6): 1926-1943, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31037616

RESUMO

The level of processing (LoP) hypothesis proposes that low-level stimulus perception (i.e., stimulus energy and features) is a graded process whereas high-level (i.e., letters, words, meaning) stimulus perception is all-or-none. In the present study, we set up a visual masking design in order to examine the nature of visual awareness at stimulus energy (i.e., detection task) and feature levels (identification task) at specific individual target durations (13, 27, 40, 53, and 80 ms). We manipulated the strength of the masking to produce different visibility conditions and gathered participants' subjective (across a 4-point awareness scale) and objective (accuracy levels) awareness performances. We found that intermediate ratings (i.e., ratings 2 and 3, which index graded awareness experiences) were used in more than 50% of the trials for target presentations of 27, 40, 53, and 80 ms. In addition, objective accuracy performances for target presentations of 27 and 80 ms produced linearly increasing detection and identification accuracies across the awareness scale categories, respectively. Overall, our results suggest that visual awareness at energy and feature levels of stimulus perception may be graded. Furthermore, we found a divergence in detection and identification performance results, which emphasizes the need for an adequate election of target durations when studying different perceptual processes such as detection versus more complex stimulus identification processes. Finally, "clarity" in the perceptual awareness scale should be exhaustively defined depending on the level of processing of the stimulus, as participants may recalibrate the meaning of the different awareness categories depending on task demands.


Assuntos
Conscientização/fisiologia , Mascaramento Perceptivo/fisiologia , Estimulação Luminosa/métodos , Percepção Visual/fisiologia , Adulto , Estado de Consciência , Feminino , Humanos , Masculino , Adulto Jovem
19.
Span J Psychol ; 21: E42, 2018 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-30355374

RESUMO

In the present study, we conducted two experiments (Experiment 1: 35 participants, M = 29; SD = 8.4; Experiment 2: 36 participants, M = 25; SD = 6.1) with the intention to explore whether underlying perceptual grouping operations and illusory form perception generate dissociable priming effects when Kanizsa-like figures are presented as primes and the rotated inducers as controls under conditions of restricted awareness. Using five different stimulus onset asynchronies (SOA conditions, Experiment 1: 27, 40 and 53 ms; Experiment 2: 27, 80 and 227 ms), we displayed masked illusory and groping primes that could be congruent or incongruent in their orientation with subsequent probe stimuli (vertical vs. horizontal). We found significant priming effects in both Experiment 1 and 2 (p < .001, η2p = .31 and p = .016, η2p = .16, respectively), but, crucially, no significant priming differences between illusory and grouping primes across SOA conditions. Overall, our results are important in showing that a dissociation of the percept generated by the grouping of the inducers from that generated by the illusory form is crucial in the study of illusory form perception under conditions of restricted awareness. In addition, they provide further evidence of perceptual organization operations occurring under very restrictive awareness conditions.


Assuntos
Conscientização/fisiologia , Percepção de Forma/fisiologia , Ilusões/fisiologia , Mascaramento Perceptivo/fisiologia , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
20.
Neuropsychologia ; 121: 144-152, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30408463

RESUMO

A crucial view in the graded vs. dichotomous debate on visual awareness proposes that its graded or dichotomous nature may depend on the depth of stimulus processing (or level of processing) associated to the experimental task. In the present study, we explored the behavioral patterns and neural correlates of different degrees of awareness associated to different depths (i.e. low vs. high) of stimulus processing. The low-level stimulus condition consisted of detecting the location of the target based on its brightness characteristics, whereas the high-level stimulus condition consisted of identifying which of four possible targets (numbers/letters) had appeared. Behavioral results showed that both subjective ratings of awareness and accuracy levels increased linearly as a function of awareness and independently of the level of stimulus processing. Additionally, the electrophysiological recordings revealed two correlates of visual awareness: enhanced posterior negativity in the N200 time window (VAN, visual awareness negativity) and enhanced positivity in the P3 time window (LP, late positivity). Interestingly, we found evidence of awareness levels modulating N200/VAN amplitudes in a graded manner only for the low-level task, whereas P3/LP amplitudes were modulated in a graded manner for both low and high-level tasks. The finding that the early posterior correlate of visual awareness (VAN at 150-250 ms) was sensitive to level of processing is consistent with task effects occurring in the visual cortex and supports the view that it is mediated by attention to task-relevant features. The amplitudes of P3/LP in both tasks correlate more directly with graded awareness and behavioral accuracy.


Assuntos
Conscientização/fisiologia , Encéfalo/fisiologia , Percepção Visual/fisiologia , Adulto , Estado de Consciência/fisiologia , Eletroencefalografia , Potenciais Evocados , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos , Adulto Jovem
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