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Humans can read and comprehend text rapidly, implying that readers might process multiple words per fixation. However, the extent to which parafoveal words are previewed and integrated into the evolving sentence context remains disputed. We investigated parafoveal processing during natural reading by recording brain activity and eye movements using MEG and an eye tracker while participants silently read one-line sentences. The sentences contained an unpredictable target word that was either congruent or incongruent with the sentence context. To measure parafoveal processing, we flickered the target words at 60 Hz and measured the resulting brain responses (i.e. Rapid Invisible Frequency Tagging, RIFT) during fixations on the pre-target words. Our results revealed a significantly weaker tagging response for target words that were incongruent with the previous context compared to congruent ones, even within 100ms of fixating the word immediately preceding the target. This reduction in the RIFT response was also found to be predictive of individual reading speed. We conclude that semantic information is not only extracted from the parafovea but can also be integrated with the previous context before the word is fixated. This early and extensive parafoveal processing supports the rapid word processing required for natural reading. Our study suggests that theoretical frameworks of natural reading should incorporate the concept of deep parafoveal processing.
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Movimentos Oculares , Leitura , Semântica , Humanos , Feminino , Masculino , Adulto , Adulto Jovem , Movimentos Oculares/fisiologia , Fóvea Central/fisiologia , Fixação Ocular/fisiologia , Magnetoencefalografia , Encéfalo/fisiologia , Compreensão/fisiologiaRESUMO
Image memorability, the likelihood that a person will remember a particular image, has been shown to be an intrinsic property of the image that is distinct from many other visual and cognitive features. Research thus far has not identified particular visual features that can sufficiently explain this intrinsic memorability, but one possibility is that more and less memorable images differ in their statistical regularity (i.e., how prototypical or distinctive they are). Statistical regularity is known to affect detection time for images, such that stimuli with higher statistical regularity can be detected with shorter presentation directions. Therefore, in the present study, we probed whether memorability affects how quickly an image can be detected. High- and low-memorability images were presented in an intact/scrambled task wherein participants were asked to indicate whether they saw an intact image or noise, and we estimated the presentation duration necessary for participants to reach 70.7% accuracy. Across two experiments using different stimulus materials, we observed and then replicated that more memorable images are associated with shorter detection thresholds than those for less memorable images. The results support the idea that memorable stimuli may better match stored templates used for image perception and/or recognition. (PsycInfo Database Record (c) 2024 APA, all rights reserved).
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Reconhecimento Visual de Modelos , Humanos , Feminino , Masculino , Adulto Jovem , Adulto , Reconhecimento Visual de Modelos/fisiologia , Reconhecimento Psicológico/fisiologia , Percepção Visual/fisiologia , Rememoração Mental/fisiologiaRESUMO
Predictive coding accounts of perception state that the brain generates perceptual predictions in the service of processing incoming sensory data. These predictions are hypothesized to be afforded by the brain's ability to internalize useful patterns, that is, statistical regularities, from the environment. We have previously argued that the N300 ERP component serves as an index of the brain's use of representations of (real-world) statistical regularities. However, we do not yet know whether overt attention is necessary in order for this process to engage. We addressed this question by presenting stimuli of either high or low real-world statistical regularity in terms of their representativeness (good/bad exemplars of natural scene categories) to participants who either fully attended the stimuli or were distracted by another task (attended/distracted conditions). Replicating past work, N300 responses were larger to bad than to good scene exemplars, and furthermore, we demonstrate minimal impacts of distraction on N300 effects. Thus, it seems that overtly focused attention is not required to maintain the brain's sensitivity to real-world statistical regularity. Furthermore, in an exploratory analysis, we showed that providing additional, artificial regularities, formed by altering the proportions of good and bad exemplars within blocks, further enhanced the N300 effect in both attended and distracted conditions, shedding light on the relationship between statistical regularities learned in the real world and those learned within the context of an experiment.
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Atenção , Encéfalo , Eletroencefalografia , Humanos , Atenção/fisiologia , Feminino , Masculino , Adulto Jovem , Encéfalo/fisiologia , Adulto , Potenciais Evocados/fisiologia , Estimulação Luminosa , Adolescente , Tempo de Reação/fisiologia , Reconhecimento Visual de Modelos/fisiologiaRESUMO
A recent study has used scalp-recorded electroencephalography to obtain evidence of semantic processing of human speech and objects by domesticated dogs. The results suggest that dogs do comprehend the meaning of familiar spoken words, in that a word can evoke the mental representation of the object to which it refers.
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Cognição , Semântica , Animais , Cães/psicologia , Cognição/fisiologia , Humanos , Eletroencefalografia , Fala/fisiologia , Percepção da Fala/fisiologia , Compreensão/fisiologiaRESUMO
Not only semantic, but also recently learned arbitrary associations have the potential to facilitate visual processing in everyday life-for example, knowledge of a (moveable) object's location at a specific time may facilitate visual processing of that object. In our prior work, we showed that previewing a scene can facilitate processing of recently associated objects at the level of visual analysis (Smith and Federmeier in Journal of Cognitive Neuroscience, 32(5):783-803, 2020). In the current study, we assess how rapidly this facilitation unfolds by manipulating scene preview duration. We then compare our results to studies using well-learned object-scene associations in a first-pass assessment of whether systems consolidation might speed up high-level visual prediction. In two ERP experiments (N = 60), we had participants study categorically organized novel object-scene pairs in an explicit paired associate learning task. At test, we varied contextual pre-exposure duration, both between (200 vs. 2500 ms) and within subjects (0-2500 ms). We examined the N300, an event-related potential component linked to high-level visual processing of objects and scenes and found that N300 effects of scene congruity increase with longer scene previews, up to approximately 1-2 s. Similar results were obtained for response times and in a separate component-neutral ERP analysis of visual template matching. Our findings contrast with prior evidence that scenes can rapidly facilitate visual processing of commonly associated objects. This raises the possibility that systems consolidation might mediate different kinds of predictive processing with different temporal profiles.
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Encéfalo , Eletroencefalografia , Humanos , Encéfalo/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa/métodos , Potenciais Evocados/fisiologiaRESUMO
Language comprehension can be facilitated by the accurate prediction of upcoming words, but prediction effects are not ubiquitous, and comprehenders likely use predictive processing to varying degrees depending on task demands. To ascertain the processing consequences of prioritizing prediction, we here compared ERPs elicited when young adult participants simply read for comprehension with those collected in a subsequent block that required active prediction. We were particularly interested in frontally-distributed post-N400 effects for expected and unexpected words in strongly constraining contexts, which have previously been documented as two distinct patterns: an enhanced positivity ("anterior positivity") observed for prediction violations compared to words that are merely unpredictable (because they occur in weakly constraining sentences) and a distinction between expected endings in more constraining contexts and those same weakly constrained words ("frontal negativity" to the strongly predicted words). We found that the size of the anterior positivity effect was unchanged between passive comprehension and active prediction, suggesting that some processes related to prediction may engage state-like networks. On the other hand, the frontal negativity showed graded patterns from the interaction of task and sentence type. These differing patterns support the hypothesis that there are two separate effects with frontal scalp distributions that occur after the N400 and further suggest that the impact of violating predictions (as long as prediction is engaged at all) is largely stable across varying levels of effort/attention directed toward prediction, whereas other comprehension processes can be modulated by task demands.
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Compreensão , Potenciais Evocados , Adulto Jovem , Humanos , Masculino , Feminino , Eletroencefalografia , Motivação , Idioma , SemânticaRESUMO
Predicting upcoming words during language comprehension not only affects processing in the moment but also has consequences for memory, although the source of these memory effects (e.g., whether driven by lingering pre-activations, re-analysis following prediction violations, or other mechanisms) remains underspecified. Here, we investigated downstream impacts of prediction on memory in two experiments. First, we recorded EEG as participants read strongly and weakly constraining sentences with expected, unexpected but plausible, or semantically anomalous endings ("He made a holster for his gun / father / train") and were tested on their recognition memory for the sentence endings. Participants showed similar rates of false alarms for predicted but never presented sentence endings whether the prediction violation was plausible or anomalous, suggesting that these arise from pre-activation of the expected words during reading. During sentence reading, especially in strongly constraining sentences, plausible prediction violations elicited an anterior positivity; anomalous endings instead elicited a posterior positivity, whose amplitude was predictive of later memory for those anomalous words. ERP patterns at the time of recognition differentiated plausible and anomalous sentence endings: Words that had been plausible prediction violations elicited enhanced late positive complex amplitudes, suggesting greater episodic recollection, whereas anomalous sentence endings elicited greater N1 amplitudes, suggesting attentional tagging. In a follow-up behavioral study, a separate group of participants read the same sentence stimuli and were tested for sentence-level recall. We found that recall of full sentences was impaired when sentences ended with a prediction violation. Taken together, the results suggest that prediction violations draw attention and affect encoding of the violating word, in a manner that depends on plausibility, and that this, in turn, may impair future memory of the gist of the sentence.
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Idioma , Semântica , Masculino , Humanos , Rememoração Mental , Reconhecimento Psicológico/fisiologia , Linguística , Leitura , Eletroencefalografia , Potenciais Evocados/fisiologia , Compreensão/fisiologiaRESUMO
Research targeting emotion's impact on relational episodic memory has largely focused on spatial aspects, but less is known about emotion's impact on memory for an event's temporal associations. The present research investigated this topic. Participants viewed a series of interspersed negative and neutral images with instructions to create stories linking successive images. Later, participants performed a surprise memory test, which measured temporal associations between pairs of consecutive pictures where one picture was negative and one was neutral. Analyses focused on how the order of negative and neutral images during encoding influenced retrieval accuracy. Converging results from a discovery study (N = 72) and pre-registered replication study (N = 150) revealed a "forward-favouring" effect of emotion in temporal memory encoding: Participants encoded associations between negative stimuli and subsequent neutral stimuli more strongly than associations between negative stimuli and preceding neutral stimuli. This finding may reflect a novel trade-off regarding emotion's effects on memory and is relevant for understanding affective disorders, as key clinical symptoms can be conceptualised as maladaptive memory retrieval of temporal details.
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In this paper, we show that Virtual Reality (VR) sickness is associated with a reduction in attention, which was detected with the P3b Event-Related Potential (ERP) component from electroencephalography (EEG) measurements collected in a dual-task paradigm. We hypothesized that sickness symptoms such as nausea, eyestrain, and fatigue would reduce the users' capacity to pay attention to tasks completed in a virtual environment, and that this reduction in attention would be dynamically reflected in a decrease of the P3b amplitude while VR sickness was experienced. In a user study, participants were taken on a tour through a museum in VR along paths with varying amounts of rotation, shown previously to cause different levels of VR sickness. While paying attention to the virtual museum (the primary task), participants were asked to silently count tones of a different frequency (the secondary task). Control measurements for comparison against the VR sickness conditions were taken when the users were not wearing the Head-Mounted Display (HMD) and while they were immersed in VR but not moving through the environment. This exploratory study shows, across multiple analyses, that the effect mean amplitude of the P3b collected during the task is associated with both sickness severity measured after the task with a questionnaire (SSQ) and with the number of counting errors on the secondary task. Thus, VR sickness may impair attention and task performance, and these changes in attention can be tracked with ERP measures as they happen, without asking participants to assess their sickness symptoms in the moment.
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Gráficos por Computador , Realidade Virtual , Humanos , Eletroencefalografia , Análise e Desempenho de Tarefas , Inquéritos e QuestionáriosRESUMO
Little is understood about how people strategically process and remember important but complex information, such as sentences. In the current study, we asked whether people can effectively prioritize memory for sentences as a function of their relative importance (operationalized as a reward point value) and whether they do so, in part, by changing their sentence processing strategies when value information is available in advance. We adapted the value-directed remembering paradigm (Castel, Psychol Learn Motiv 48:225-270, 2007) for sentences that varied in constraint and predictability. Each sentence was associated with a high or low value for subsequent free recall (whole sentence) and recognition (sentence-final words) tests. Value information appeared after or before each sentence as a between-subject manipulation. Regardless of condition, we observed that high-value sentences were recalled more often than low-value sentences, showing that people can strategically prioritize their encoding of sentences. However, memory patterns differed depending on when value information was available. Recall for high-value sentences that ended unexpectedly (and therefore violated one's predictions) was reduced in the Before compared to the After condition. Before condition participants also showed a greater tendency to false alarm to lures (words that were the predicted - but not obtained - ending) from strongly constraining sentences. These observations suggest that when people try to prioritize sentence-level information that they know is valuable, the reading strategies they employ may paradoxically lead to worse memory.
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Idioma , Leitura , Humanos , Rememoração Mental , Aprendizagem , Reconhecimento PsicológicoRESUMO
BACKGROUND: The use of prediction can aid language comprehension through preactivation of relevant word features. However, predictions can be wrong, and it has been proposed that resolving the mismatch between the predicted and presented item requires cognitive resources. Older adults tend not to predict and instead rely more on passive comprehension. Here, we tested, using an intraindividual approach, whether older adults consistently use this less demanding processing strategy while reading or whether they attempt to predict on some trials. METHODS: We used a cross-task conflict paradigm. Younger and older participants self-paced to read sentences that ended with either an expected or unexpected word. Each sentence was then followed by a flanker stimulus that could be congruent or incongruent. We examined responses within and across the two tasks. RESULTS: Unexpected words were in general read as quickly as expected words, indicating that typical processing of these words was similar. However, for both younger and older adults, there was a greater proportion of very slow trials for unexpected words, revealing different processing on a subset of trials. Critically, in older adults, these slowly read unexpected words engaged control, as seen in speeded responses to incongruent flanker stimuli. CONCLUSION: Using a cross-task conflict paradigm, we showed that older adults are able to predict and engage cognitive resources to cope with prediction violations, but do not opt to use these processes consistently.
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To understand how neural networks in the left (LH) and right (RH) cerebral hemispheres contribute to different aspects of language comprehension, in two experiments we measured event-related potentials (ERPs) as right-handed participants read sentences, some of which contained morphosyntactic and thematic role violations. Replicating prior work (Kuperberg et al., 2006), in Experiment 1 thematic role violations elicited both an N400 and a (semantic) P600 effect. Morphosyntactic violations elicited effects that differed as a function of participants' familial sinistrality (the presence [FS+] or absence [FS-] of a left-handed biological relative): FS+ participants showed a (syntactic) P600 effect whereas FS- participants showed a biphasic N400 and P600 response. To assess whether this difference reflects different underlying patterns of lateralization, in Experiment 2 target words were presented using visual half-field (VF) presentation. Indeed, for morphosyntactic violations, the FS- group elicited an asymmetric pattern, showing a P600 effect only with LH-biased presentation and an N400 effect in both VFs (cf. Lee and Federmeier, 2015). In contrast, FS+ participants showed a bilateral (N400-only) response pattern. This provides further evidence of FS-based differences in hemispheric contributions to syntactic processing. Strikingly, we found that, when lateralized, thematic role violations did not elicit a P600 effect, suggesting that this effect requires contributions from both hemispheres. The different response patterns for morphosyntactic and thematic role animacy violations across FS and VF also point to a processing difference in the comprehension mechanisms underlying the semantic and syntactic P600, which had heretofore been assumed to be variants of the same component.
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Potenciais Evocados , Semântica , Humanos , Masculino , Feminino , Potenciais Evocados/fisiologia , Eletroencefalografia , Idioma , Leitura , Compreensão/fisiologiaRESUMO
Stimuli are easier to process when context makes them predictable, but does context-based facilitation arise from preactivation of a limited set of relatively probable upcoming stimuli (with facilitation then linearly related to probability) or, instead, because the system maintains and updates a probability distribution across all items (with facilitation logarithmically related to probability)? We measured the N400, an index of semantic access, to words of varying probability, including unpredictable words. Word predictability was measured using both cloze probabilities and a state-of-the-art machine learning language model (GPT-2). We reanalyzed five datasets (n = 138) to demonstrate and then replicate that context-based facilitation on the N400 is graded, even among unpredictable words. Furthermore, we established that the relationship between word predictability and context-based facilitation combines linear and logarithmic functions. We argue that this composite function reveals properties of the mapping between words and semantic features and how feature- and word-related information is activated on-line.
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Normal aging has variable effects on language comprehension, perhaps because comprehension mechanisms vary in their dependence on network structure versus network dynamics. To test claims that processing dynamics are more affected by age than structure, we used EEG to measure and compare the impact of neighborhood size, a core measure of the structure of the lexico-semantic network, and repetition, a simple measure of processing dynamics, on single word processing. Older adults showed robust effects of neighborhood size on the N400, comparable to those elicited by young adults, but reduced effects of repetition. Furthermore, older adults with greater verbal fluency, print exposure, and reading comprehension showed greater repetition effects, suggesting some older adults can maintain processing dynamics that are similar to those of young adults. Thus, the organizational structure of the semantic network seems stable across normal aging, but (some) older adults may struggle to adjust activation states within that network.
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To test theories that posit differences in how semantic information is represented in the cerebral hemispheres, we assessed semantic priming for associatively and categorically related prime-target pairs that were graded in relatedness strength. Visual half-field presentation was used to bias processing to the right or left hemisphere, and event-related potential (ERP) and behavioral responses were measured while participants completed a semantic relatedness judgement task. Contrary to theories positing representational differences across the cerebral hemispheres, in two experiments using (1) centralized prime presentation and lateralized targets and (2) lateralized primes and targets, we found similar priming patterns across the two hemispheres at the level of semantic access (N400), on later measures of explicit processing (late positive complex; LPC), and in behavioral response speeds and accuracy. We argue that hemispheric differences, when they arise, are more likely due to differences in task demands than in how the hemispheres fundamentally represent semantic information.
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Potenciais Evocados , Semântica , Eletroencefalografia , Potenciais Evocados/fisiologia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino , Tempo de Reação/fisiologiaRESUMO
Our behavior is shaped by multiple factors, including direct feedback (seeing the outcomes of our past actions) and social observation (in part, via a drive to conform to other peoples' behaviors). However, it remains unclear how these two processes are linked in the context of behavioral change. This is important to investigate, as behavioral change is associated with distinct neural correlates that reflect specific aspects of processing, such as information integration and rule updating. To clarify whether these processes characterize both direct learning and conformity, we elicited the two within the same task, using a role-swapping version of the Ultimatum Game-a fairness paradigm where subjects decide how to share a pot of money with other players-while electroencephalography (EEG) data were recorded. Behavioral results showed that subjects decided how to divide the pot based on both direct feedback (seeing whether their past proposals were accepted or rejected) and social observation (copying the splits that others just proposed). Converging EEG evidence revealed that increased centroparietal positivity (P2, P3b, and late positivity) indexed behavioral changes motivated by direct feedback and those motivated by drives to conform. However, exploratory analyses also suggest that these two motivating factors may also be dissociable, and that frontal midline theta oscillations may predict behavioral changes linked to direct feedback but not conformity. Overall, this study provides novel electrophysiological evidence regarding the different forms of behavioral change. These findings are also relevant for understanding the mechanisms of social information processing that underlie successful cooperation.
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Eletroencefalografia , Conformidade Social , Fenômenos Eletrofisiológicos , Potenciais Evocados , Retroalimentação , Humanos , Comportamento SocialRESUMO
Can a single adjective immediately influence message-building during sentence processing? We presented participants with 168 sentence contexts, such as "His skin was red from spending the day at the " Sentences ended with either the most expected word ("beach") or a low cloze probability completion ("pool"). Nouns were preceded by adjectives that changed their relative likelihood (e.g., "neighborhood" increases the cloze probability of pool whereas "sandy" promotes beach). We asked if participants' online processing can be rapidly updated by the adjective, changing the resulting pattern of facilitation at the noun, and, if so, whether updates unfold symmetrically-not only increasing, but also decreasing, the fit of particular nouns. We measured event-related potentials (ERPs) to the adjective and the noun and modeled these with respect to (a) the overall amount of updating promoted by the adjective, (b) the preadjectival cloze probability of the noun and, (c) the amount of cloze probability change for the obtained noun after the adjective. Bayesian mixed-effects analysis of N400 amplitude at the noun revealed that adjectives rapidly influenced semantic processing of the noun, but did so asymmetrically, with positive updating (reducing N400 amplitudes) having a greater effect than negative updating (increasing N400s). At the adjective, the amount of (possible) updating was not associated with any discernible ERP modulation. Overall, these results suggest the information provided by adjectives is buffered until a head noun is encountered, at which point the access of the noun's semantics is shaped in parallel by both the adjective and the sentence-level representation. (PsycInfo Database Record (c) 2022 APA, all rights reserved).
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Eletroencefalografia , Potenciais Evocados , Teorema de Bayes , Feminino , Humanos , Idioma , Masculino , SemânticaRESUMO
OBJECTIVE: Alcohol cue salience is considered core to the broader understanding of drinking behaviors. In the present research, we sought to build the knowledge of alcohol cue salience by exploring P3 responses to alcohol images among social drinkers within a large-scale alcohol-administration study. METHOD: Participants (N = 246) were randomly assigned to receive either a moderate dose of alcohol (target BAC = .08%) or a nonalcoholic control beverage. Following beverage administration, participants engaged in image-viewing tasks while EEG was recorded. We examined the impact of alcohol on the amplitude of P3 responses to pictures of alcoholic versus nonalcoholic beverages, exploring both beverage-manipulation and individual-difference moderators of these effects. RESULTS: Results revealed a significant effect of acute alcohol intoxication on P3 responses across stimulus types, with the overall amplitude of P3 being significantly smaller among participants consuming alcohol versus a nonalcoholic beverage. In addition, results revealed a significant main effect of image type, such that P3 amplitude was larger for alcohol images compared to nonalcohol images. No interactions emerged between stimulus type and beverage condition or stimulus type and AUD risk level. CONCLUSIONS: With the aim of better understanding the potential influence of the broader context on responses to individual cues, the present study examined the perceived salience of alcohol cues within a drinking setting. Findings provide evidence for alcohol cue salience that is both robust and also widespread across drinkers. More generally, the present study's findings may offer new directions for understanding neurocognitive processes of alcohol cue salience across contexts. (PsycInfo Database Record (c) 2022 APA, all rights reserved).
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Intoxicação Alcoólica , Alcoolismo , Humanos , Intoxicação Alcoólica/psicologia , Sinais (Psicologia) , Consumo de Bebidas Alcoólicas/psicologia , Alcoolismo/psicologia , Etanol/farmacologia , EncéfaloRESUMO
The ability to rapidly and systematically access knowledge stored in long-term memory in response to incoming sensory information-that is, to derive meaning from the world-lies at the core of human cognition. Research using methods that can precisely track brain activity over time has begun to reveal the multiple cognitive and neural mechanisms that make this possible. In this article, I delineate how a process of connecting affords an effortless, continuous infusion of meaning into human perception. In a relatively invariant time window, uncovered through studies using the N400 component of the event-related potential, incoming sensory information naturally induces a graded landscape of activation across long-term semantic memory, creating what might be called "proto-concepts". Connecting can be (but is not always) followed by a process of further considering those activations, wherein a set of more attentionally demanding "active comprehension" mechanisms mediate the selection, augmentation, and transformation of the initial semantic representations. The result is a limited set of more stable bindings that can be arranged in time or space, revised as needed, and brought to awareness. With this research, we are coming closer to understanding how the human brain is able to fluidly link sensation to experience, to appreciate language sequences and event structures, and, sometimes, to even predict what might be coming up next.
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Atenção , Compreensão/fisiologia , Eletrofisiologia , Potenciais Evocados/fisiologia , Idioma , Semântica , Encéfalo/fisiologia , Cognição/fisiologia , Eletroencefalografia , Humanos , Memória/fisiologiaRESUMO
Predictive coding models can simulate known perceptual or neuronal phenomena, but there have been fewer attempts to identify a reliable neural signature of predictive coding for complex stimuli. In a pair of studies, we test whether the N300 component of the event-related potential, occurring 250-350-ms poststimulus-onset, has the response properties expected for such a signature of perceptual hypothesis testing at the level of whole objects and scenes. We show that N300 amplitudes are smaller to representative ("good exemplars") compared with less representative ("bad exemplars") items from natural scene categories. Integrating these results with patterns observed for objects, we establish that, across a variety of visual stimuli, the N300 is responsive to statistical regularity, or the degree to which the input is "expected" (either explicitly or implicitly) based on prior knowledge, with statistically regular images evoking a reduced response. Moreover, we show that the measure exhibits context-dependency; that is, we find the N300 sensitivity to category representativeness when stimuli are congruent with, but not when they are incongruent with, a category pre-cue. Thus, we argue that the N300 is the best candidate to date for an index of perceptual hypotheses testing for complex visual objects and scenes.