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1.
Front Psychol ; 11: 1504, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760320

RESUMO

Information processing in neural systems can be described and analyzed at multiple spatiotemporal scales. Generally, information at lower levels is more fine-grained but can be coarse-grained at higher levels. However, only information processed at specific scales of coarse-graining appears to be available for conscious awareness. We do not have direct experience of information available at the scale of individual neurons, which is noisy and highly stochastic. Neither do we have experience of more macro-scale interactions, such as interpersonal communications. Neurophysiological evidence suggests that conscious experiences co-vary with information encoded in coarse-grained neural states such as the firing pattern of a population of neurons. In this article, we introduce a new informational theory of consciousness: Information Closure Theory of Consciousness (ICT). We hypothesize that conscious processes are processes which form non-trivial informational closure (NTIC) with respect to the environment at certain coarse-grained scales. This hypothesis implies that conscious experience is confined due to informational closure from conscious processing to other coarse-grained scales. Information Closure Theory of Consciousness (ICT) proposes new quantitative definitions of both conscious content and conscious level. With the parsimonious definitions and a hypothesize, ICT provides explanations and predictions of various phenomena associated with consciousness. The implications of ICT naturally reconcile issues in many existing theories of consciousness and provides explanations for many of our intuitions about consciousness. Most importantly, ICT demonstrates that information can be the common language between consciousness and physical reality.

2.
Front Neurorobot ; 12: 88, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30723402

RESUMO

This paper presents the Homeo-Heterostatic Value Gradients (HHVG) algorithm as a formal account on the constructive interplay between boredom and curiosity which gives rise to effective exploration and superior forward model learning. We offer an instrumental view of action selection, in which an action serves to disclose outcomes that have intrinsic meaningfulness to an agent itself. This motivated two central algorithmic ingredients: devaluation and devaluation progress, both underpin agent's cognition concerning intrinsically generated rewards. The two serve as an instantiation of homeostatic and heterostatic intrinsic motivation. A key insight from our algorithm is that the two seemingly opposite motivations can be reconciled-without which exploration and information-gathering cannot be effectively carried out. We supported this claim with empirical evidence, showing that boredom-enabled agents consistently outperformed other curious or explorative agent variants in model building benchmarks based on self-assisted experience accumulation.

3.
J Neurosci ; 37(35): 8486-8497, 2017 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-28765331

RESUMO

A novel neural signature of active visual processing has recently been described in the form of the "perceptual echo", in which the cross-correlation between a sequence of randomly fluctuating luminance values and occipital electrophysiological signals exhibits a long-lasting periodic (∼100 ms cycle) reverberation of the input stimulus (VanRullen and Macdonald, 2012). As yet, however, the mechanisms underlying the perceptual echo and its function remain unknown. Reasoning that natural visual signals often contain temporally predictable, though nonperiodic features, we hypothesized that the perceptual echo may reflect a periodic process associated with regularity learning. To test this hypothesis, we presented subjects with successive repetitions of a rapid nonperiodic luminance sequence, and examined the effects on the perceptual echo, finding that echo amplitude linearly increased with the number of presentations of a given luminance sequence. These data suggest that the perceptual echo reflects a neural signature of regularity learning.Furthermore, when a set of repeated sequences was followed by a sequence with inverted luminance polarities, the echo amplitude decreased to the same level evoked by a novel stimulus sequence. Crucially, when the original stimulus sequence was re-presented, the echo amplitude returned to a level consistent with the number of presentations of this sequence, indicating that the visual system retained sequence-specific information, for many seconds, even in the presence of intervening visual input. Altogether, our results reveal a previously undiscovered regularity learning mechanism within the human visual system, reflected by the perceptual echo.SIGNIFICANCE STATEMENT How the brain encodes and learns fast-changing but nonperiodic visual input remains unknown, even though such visual input characterizes natural scenes. We investigated whether the phenomenon of "perceptual echo" might index such learning. The perceptual echo is a long-lasting reverberation between a rapidly changing visual input and evoked neural activity, apparent in cross-correlations between occipital EEG and stimulus sequences, peaking in the alpha (∼10 Hz) range. We indeed found that perceptual echo is enhanced by repeatedly presenting the same visual sequence, indicating that the human visual system can rapidly and automatically learn regularities embedded within fast-changing dynamic sequences. These results point to a previously undiscovered regularity learning mechanism, operating at a rate defined by the alpha frequency.


Assuntos
Aprendizagem/fisiologia , Potenciação de Longa Duração/fisiologia , Rede Nervosa/fisiologia , Estimulação Luminosa , Córtex Visual/fisiologia , Percepção Visual/fisiologia , Adolescente , Adulto , Atenção/fisiologia , Feminino , Humanos , Masculino , Adulto Jovem
4.
Conscious Cogn ; 31: 139-47, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25486340

RESUMO

Despite accumulating evidence that perceptual predictions influence perceptual content, the relations between these predictions and conscious contents remain unclear, especially for cross-modal predictions. We examined whether predictions of visual events by auditory cues can facilitate conscious access to the visual stimuli. We trained participants to learn associations between auditory cues and colour changes. We then asked whether congruency between auditory cues and target colours would speed access to consciousness. We did this by rendering a visual target subjectively invisible using motion-induced blindness and then gradually changing its colour while presenting congruent or incongruent auditory cues. Results showed that the visual target gained access to consciousness faster in congruent than in incongruent trials; control experiments excluded potentially confounding effects of attention and motor response. The expectation effect was gradually established over blocks suggesting a role for extensive training. Overall, our findings show that predictions learned through cross-modal training can facilitate conscious access to visual stimuli.


Assuntos
Estimulação Acústica , Percepção Auditiva/fisiologia , Estado de Consciência/fisiologia , Aprendizagem/fisiologia , Estimulação Luminosa , Percepção Visual/fisiologia , Adolescente , Adulto , Atenção/fisiologia , Sinais (Psicologia) , Feminino , Humanos , Masculino , Tempo de Reação/fisiologia , Adulto Jovem
5.
Psychol Sci ; 22(12): 1567-73, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22042728

RESUMO

To reproduce the duration of an event precisely, one needs to represent the temporal information without being influenced by other magnitude attributes (e.g., size) of the event. In the present study, however, task-irrelevant numerical magnitude automatically affected participants' reproduction of the duration of a stimulus. In Experiment 1, participants made key-press responses to reproduce the duration of numbers. Reproduced durations were shorter for small numbers (e.g., 1) than for large numbers (e.g., 9). In contrast, in Experiment 2, participants' reproductions of a standard duration were longer when their key-press response was accompanied by visual presentation of a small number than when it was accompanied by presentation of a large number. These results clearly demonstrate that number-time interference extends beyond simple mapping between stimulus categories and response alternatives. The findings support the notion that either a common magnitude representation or closely connected magnitude representations underlie numerical and temporal processing.


Assuntos
Cognição , Percepção do Tempo , Humanos , Desempenho Psicomotor
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