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1.
Cereb Cortex ; 33(8): 4478-4497, 2023 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-36130089

RESUMEN

We used magnetoencephalography (MEG) and event-related potentials (ERPs) to track the time-course and localization of evoked activity produced by expected, unexpected plausible, and implausible words during incremental language comprehension. We suggest that the full pattern of results can be explained within a hierarchical predictive coding framework in which increased evoked activity reflects the activation of residual information that was not already represented at a given level of the fronto-temporal hierarchy ("error" activity). Between 300 and 500 ms, the three conditions produced progressively larger responses within left temporal cortex (lexico-semantic prediction error), whereas implausible inputs produced a selectively enhanced response within inferior frontal cortex (prediction error at the level of the event model). Between 600 and 1,000 ms, unexpected plausible words activated left inferior frontal and middle temporal cortices (feedback activity that produced top-down error), whereas highly implausible inputs activated left inferior frontal cortex, posterior fusiform (unsuppressed orthographic prediction error/reprocessing), and medial temporal cortex (possibly supporting new learning). Therefore, predictive coding may provide a unifying theory that links language comprehension to other domains of cognition.


Asunto(s)
Mapeo Encefálico , Comprensión , Comprensión/fisiología , Mapeo Encefálico/métodos , Semántica , Magnetoencefalografía/métodos , Lóbulo Frontal/fisiología
2.
J Neurosci ; 40(16): 3278-3291, 2020 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-32161141

RESUMEN

It has been proposed that people can generate probabilistic predictions at multiple levels of representation during language comprehension. We used magnetoencephalography (MEG) and electroencephalography (EEG), in combination with representational similarity analysis, to seek neural evidence for the prediction of animacy features. In two studies, MEG and EEG activity was measured as human participants (both sexes) read three-sentence scenarios. Verbs in the final sentences constrained for either animate or inanimate semantic features of upcoming nouns, and the broader discourse context constrained for either a specific noun or for multiple nouns belonging to the same animacy category. We quantified the similarity between spatial patterns of brain activity following the verbs until just before the presentation of the nouns. The MEG and EEG datasets revealed converging evidence that the similarity between spatial patterns of neural activity following animate-constraining verbs was greater than following inanimate-constraining verbs. This effect could not be explained by lexical-semantic processing of the verbs themselves. We therefore suggest that it reflected the inherent difference in the semantic similarity structure of the predicted animate and inanimate nouns. Moreover, the effect was present regardless of whether a specific word could be predicted, providing strong evidence for the prediction of coarse-grained semantic features that goes beyond the prediction of individual words.SIGNIFICANCE STATEMENT Language inputs unfold very quickly during real-time communication. By predicting ahead, we can give our brains a "head start," so that language comprehension is faster and more efficient. Although most contexts do not constrain strongly for a specific word, they do allow us to predict some upcoming information. For example, following the context of "they cautioned the…," we can predict that the next word will be animate rather than inanimate (we can caution a person, but not an object). Here, we used EEG and MEG techniques to show that the brain is able to use these contextual constraints to predict the animacy of upcoming words during sentence comprehension, and that these predictions are associated with specific spatial patterns of neural activity.


Asunto(s)
Encéfalo/fisiología , Comprensión/fisiología , Lenguaje , Lectura , Adolescente , Adulto , Electroencefalografía , Femenino , Humanos , Magnetoencefalografía , Masculino , Adulto Joven
3.
J Cogn Neurosci ; 32(1): 12-35, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31479347

RESUMEN

It has been proposed that hierarchical prediction is a fundamental computational principle underlying neurocognitive processing. Here, we ask whether the brain engages distinct neurocognitive mechanisms in response to inputs that fulfill versus violate strong predictions at different levels of representation during language comprehension. Participants read three-sentence scenarios in which the third sentence constrained for a broad event structure, for example, {Agent caution animate-Patient}. High constraint contexts additionally constrained for a specific event/lexical item, for example, a two-sentence context about a beach, lifeguards, and sharks constrained for the event, {Lifeguards cautioned Swimmers}, and the specific lexical item swimmers. Low constraint contexts did not constrain for any specific event/lexical item. We measured ERPs on critical nouns that fulfilled and/or violated each of these constraints. We found clear, dissociable effects to fulfilled semantic predictions (a reduced N400), to event/lexical prediction violations (an increased late frontal positivity), and to event structure/animacy prediction violations (an increased late posterior positivity/P600). We argue that the late frontal positivity reflects a large change in activity associated with successfully updating the comprehender's current situation model with new unpredicted information. We suggest that the late posterior positivity/P600 is triggered when the comprehender detects a conflict between the input and her model of the communicator and communicative environment. This leads to an initial failure to incorporate the unpredicted input into the situation model, which may be followed by second-pass attempts to make sense of the discourse through reanalysis, repair, or reinterpretation. Together, these findings provide strong evidence that confirmed and violated predictions at different levels of representation manifest as distinct spatiotemporal neural signatures.


Asunto(s)
Anticipación Psicológica/fisiología , Corteza Cerebral/fisiología , Comprensión/fisiología , Conflicto Psicológico , Potenciales Evocados/fisiología , Psicolingüística , Lectura , Adulto , Electroencefalografía , Femenino , Humanos , Masculino , Reconocimiento Visual de Modelos/fisiología , Adulto Joven
4.
Psychol Med ; 49(8): 1335-1345, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30131083

RESUMEN

BACKGROUND: People with schizophrenia process language in unusual ways, but the causes of these abnormalities are unclear. In particular, it has proven difficult to empirically disentangle explanations based on impairments in the top-down processing of higher level information from those based on the bottom-up processing of lower level information. METHODS: To distinguish these accounts, we used visual-world eye tracking, a paradigm that measures spoken language processing during real-world interactions. Participants listened to and then acted out syntactically ambiguous spoken instructions (e.g. 'tickle the frog with the feather', which could either specify how to tickle a frog, or which frog to tickle). We contrasted how 24 people with schizophrenia and 24 demographically matched controls used two types of lower level information (prosody and lexical representations) and two types of higher level information (pragmatic and discourse-level representations) to resolve the ambiguous meanings of these instructions. Eye tracking allowed us to assess how participants arrived at their interpretation in real time, while recordings of participants' actions measured how they ultimately interpreted the instructions. RESULTS: We found a striking dissociation in participants' eye movements: the two groups were similarly adept at using lower level information to immediately constrain their interpretations of the instructions, but only controls showed evidence of fast top-down use of higher level information. People with schizophrenia, nonetheless, did eventually reach the same interpretations as controls. CONCLUSIONS: These data suggest that language abnormalities in schizophrenia partially result from a failure to use higher level information in a top-down fashion, to constrain the interpretation of language as it unfolds in real time.


Asunto(s)
Comprensión , Movimientos Oculares , Lenguaje , Esquizofrenia/fisiopatología , Percepción del Habla , Adulto , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Psicología del Esquizofrénico , Percepción Visual
5.
Psychol Med ; 49(10): 1740-1748, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30178729

RESUMEN

BACKGROUND: The visual system is recognized as an important site of pathology and dysfunction in schizophrenia. In this study, we evaluated different visual perceptual functions in patients with psychotic disorders using a potentially clinically applicable task battery and assessed their relationship with symptom severity in patients, and with schizotypal features in healthy participants. METHODS: Five different areas of visual functioning were evaluated in patients with schizophrenia and schizoaffective disorder (n = 28) and healthy control subjects (n = 31) using a battery that included visuospatial working memory (VSWM), velocity discrimination (VD), contour integration, visual context processing, and backward masking tasks. RESULTS: The patient group demonstrated significantly lower performance in VD, contour integration, and VSWM tasks. Performance did not differ between the two groups on the visual context processing task and did not differ across levels of interstimulus intervals in the backward masking task. Performances on VSWM, VD, and contour integration tasks were correlated with negative symptom severity but not with other symptom dimensions in the patient group. VSWM and VD performances were also correlated with negative sychizotypal features in healthy controls. CONCLUSION: Taken together, these results demonstrate significant abnormalities in multiple visual processing tasks in patients with psychotic disorders, adding to the literature implicating visual abnormalities in these conditions. Furthermore, our results show that visual processing impairments are associated with the negative symptom dimension in patients as well as healthy individuals.


Asunto(s)
Trastornos de la Percepción/fisiopatología , Trastornos Psicóticos/fisiopatología , Esquizofrenia/fisiopatología , Trastorno de la Personalidad Esquizotípica/fisiopatología , Percepción Visual/fisiología , Adolescente , Adulto , Femenino , Humanos , Masculino , Memoria a Corto Plazo/fisiología , Persona de Mediana Edad , Percepción de Movimiento/fisiología , Reconocimiento Visual de Modelos/fisiología , Trastornos de la Percepción/etiología , Trastornos Psicóticos/complicaciones , Esquizofrenia/complicaciones , Trastorno de la Personalidad Esquizotípica/complicaciones , Percepción Espacial/fisiología , Adulto Joven
6.
Cereb Cortex ; 26(4): 1377-87, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25316341

RESUMEN

Although there is broad agreement that top-down expectations can facilitate lexical-semantic processing, the mechanisms driving these effects are still unclear. In particular, while previous electroencephalography (EEG) research has demonstrated a reduction in the N400 response to words in a supportive context, it is often challenging to dissociate facilitation due to bottom-up spreading activation from facilitation due to top-down expectations. The goal of the current study was to specifically determine the cortical areas associated with facilitation due to top-down prediction, using magnetoencephalography (MEG) recordings supplemented by EEG and functional magnetic resonance imaging (fMRI) in a semantic priming paradigm. In order to modulate expectation processes while holding context constant, we manipulated the proportion of related pairs across 2 blocks (10 and 50% related). Event-related potential results demonstrated a larger N400 reduction when a related word was predicted, and MEG source localization of activity in this time-window (350-450 ms) localized the differential responses to left anterior temporal cortex. fMRI data from the same participants support the MEG localization, showing contextual facilitation in left anterior superior temporal gyrus for the high expectation block only. Together, these results provide strong evidence that facilitatory effects of lexical-semantic prediction on the electrophysiological response 350-450 ms postonset reflect modulation of activity in left anterior temporal cortex.


Asunto(s)
Semántica , Lóbulo Temporal/fisiología , Adolescente , Adulto , Mapeo Encefálico , Electroencefalografía , Potenciales Evocados , Femenino , Lateralidad Funcional , Humanos , Imagen por Resonancia Magnética , Magnetoencefalografía , Masculino , Lectura , Procesamiento de Señales Asistido por Computador , Adulto Joven
7.
Cogn Affect Behav Neurosci ; 16(3): 415-32, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26833048

RESUMEN

In this study, we used event-related potentials to examine how different dimensions of emotion-valence and arousal-influence different stages of word processing under different task demands. In two experiments, two groups of participants viewed the same single emotional and neutral words while carrying out different tasks. In both experiments, valence (pleasant, unpleasant, and neutral) was fully crossed with arousal (high and low). We found that the task made a substantial contribution to how valence and arousal modulated the late positive complex (LPC), which is thought to reflect sustained evaluative processing (particularly of emotional stimuli). When participants performed a semantic categorization task in which emotion was not directly relevant to task performance, the LPC showed a larger amplitude for high-arousal than for low-arousal words, but no effect of valence. In contrast, when participants performed an overt valence categorization task, the LPC showed a large effect of valence (with unpleasant words eliciting the largest positivity), but no effect of arousal. These data show not only that valence and arousal act independently to influence word processing, but that their relative contributions to prolonged evaluative neural processes are strongly influenced by the situational demands (and by individual differences, as revealed in a subsequent analysis of subjective judgments).


Asunto(s)
Nivel de Alerta/fisiología , Mapeo Encefálico , Emociones/fisiología , Potenciales Evocados/fisiología , Reconocimiento Visual de Modelos/fisiología , Adolescente , Adulto , Electroencefalografía/métodos , Femenino , Humanos , Masculino , Análisis y Desempeño de Tareas , Adulto Joven
8.
J Neurosci ; 33(43): 17174-81, 2013 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-24155321

RESUMEN

A core property of human semantic processing is the rapid, facilitatory influence of prior input on extracting the meaning of what comes next, even under conditions of minimal awareness. Previous work has shown a number of neurophysiological indices of this facilitation, but the mapping between time course and localization-critical for separating automatic semantic facilitation from other mechanisms-has thus far been unclear. In the current study, we used a multimodal imaging approach to isolate early, bottom-up effects of context on semantic memory, acquiring a combination of electroencephalography (EEG), magnetoencephalography (MEG), and functional magnetic resonance imaging (fMRI) measurements in the same individuals with a masked semantic priming paradigm. Across techniques, the results provide a strikingly convergent picture of early automatic semantic facilitation. Event-related potentials demonstrated early sensitivity to semantic association between 300 and 500 ms; MEG localized the differential neural response within this time window to the left anterior temporal cortex, and fMRI localized the effect more precisely to the left anterior superior temporal gyrus, a region previously implicated in semantic associative processing. However, fMRI diverged from early EEG/MEG measures in revealing semantic enhancement effects within frontal and parietal regions, perhaps reflecting downstream attempts to consciously access the semantic features of the masked prime. Together, these results provide strong evidence that automatic associative semantic facilitation is realized as reduced activity within the left anterior superior temporal cortex between 300 and 500 ms after a word is presented, and emphasize the importance of multimodal neuroimaging approaches in distinguishing the contributions of multiple regions to semantic processing.


Asunto(s)
Semántica , Lóbulo Temporal/fisiología , Adolescente , Adulto , Asociación , Mapeo Encefálico , Potenciales Evocados , Femenino , Lóbulo Frontal/fisiología , Humanos , Masculino , Memoria , Lóbulo Parietal/fisiología , Enmascaramiento Perceptual , Pruebas de Asociación de Palabras
9.
J Cogn Neurosci ; 26(9): 1905-17, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24702457

RESUMEN

The verb "pounce" describes a single, near-instantaneous event. Yet, we easily understand that, "For several minutes the cat pounced…" describes a situation in which multiple pounces occurred, although this interpretation is not overtly specified by the sentence's syntactic structure or by any of its individual words--a phenomenon known as "aspectual coercion." Previous psycholinguistic studies have reported processing costs in association with aspectual coercion, but the neurocognitive mechanisms giving rise to these costs remain contentious. Additionally, there is some controversy about whether readers commit to a full interpretation of the event when the aspectual information becomes available, or whether they leave it temporarily underspecified until later in the sentence. Using ERPs, we addressed these questions in a design that fully crossed context type (punctive, durative, frequentative) with verb type (punctive, durative). We found a late, sustained negativity to punctive verbs in durative contexts, but not in frequentative (e.g., explicitly iterative) contexts. This effect was distinct from the N400 in both its time course and scalp distribution, suggesting that it reflected a different underlying neurocognitive mechanism. We also found that ERPs to durative verbs were unaffected by context type. Together, our results provide strong evidence that neural activity associated with aspectual coercion is driven by the engagement of a morphosyntactically unrealized semantic operator rather than by violations of real-world knowledge, more general shifts in event representation, or event iterativity itself. More generally, our results add to a growing body of evidence that a set of late-onset sustained negativities reflect elaborative semantic processing that goes beyond simply combining the meaning of individual words with syntactic structure to arrive at a final representation of meaning.


Asunto(s)
Mapeo Encefálico , Encéfalo/fisiología , Cognición/fisiología , Potenciales Evocados/fisiología , Semántica , Adolescente , Adulto , Análisis de Varianza , Comprensión , Electroencefalografía , Femenino , Humanos , Masculino , Psicolingüística , Tiempo de Reacción/fisiología , Adulto Joven
10.
Cognition ; 246: 105755, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38428168

RESUMEN

The N400 event-related component has been widely used to investigate the neural mechanisms underlying real-time language comprehension. However, despite decades of research, there is still no unifying theory that can explain both its temporal dynamics and functional properties. In this work, we show that predictive coding - a biologically plausible algorithm for approximating Bayesian inference - offers a promising framework for characterizing the N400. Using an implemented predictive coding computational model, we demonstrate how the N400 can be formalized as the lexico-semantic prediction error produced as the brain infers meaning from the linguistic form of incoming words. We show that the magnitude of lexico-semantic prediction error mirrors the functional sensitivity of the N400 to various lexical variables, priming, contextual effects, as well as their higher-order interactions. We further show that the dynamics of the predictive coding algorithm provides a natural explanation for the temporal dynamics of the N400, and a biologically plausible link to neural activity. Together, these findings directly situate the N400 within the broader context of predictive coding research. More generally, they raise the possibility that the brain may use the same computational mechanism for inference across linguistic and non-linguistic domains.


Asunto(s)
Electroencefalografía , Potenciales Evocados , Humanos , Masculino , Femenino , Teorema de Bayes , Semántica , Encéfalo , Comprensión
11.
J Neurosci ; 32(13): 4482-94, 2012 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-22457496

RESUMEN

Active reading requires coordination between frequent eye movements (saccades) and short fixations in text. Yet, the impact of saccades on word processing remains unknown, as neuroimaging studies typically employ constant eye fixation. Here we investigate eye-movement effects on word recognition processes in healthy human subjects using anatomically constrained magnetoencephalography, psychophysical measurements, and saccade detection in real time. Word recognition was slower and brain responses were reduced to words presented early versus late after saccades, suggesting an overall transient impairment of word processing after eye movements. Response reductions occurred early in visual cortices and later in language regions, where they colocalized with repetition priming effects. Qualitatively similar effects occurred when words appeared early versus late after background movement that mimicked saccades, suggesting that retinal motion contributes to postsaccadic inhibition. Further, differences in postsaccadic and background-movement effects suggest that central mechanisms also contribute to postsaccadic modulation. Together, these results suggest a complex interplay between visual and central saccadic mechanisms during reading.


Asunto(s)
Mapeo Encefálico/psicología , Corteza Cerebral/fisiología , Procesos Mentales/fisiología , Lectura , Reconocimiento en Psicología/fisiología , Movimientos Sacádicos/fisiología , Adulto , Mapeo Encefálico/métodos , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Imagen por Resonancia Magnética/psicología , Magnetoencefalografía/métodos , Magnetoencefalografía/psicología , Masculino , Estimulación Luminosa/métodos , Memoria Implícita/fisiología , Percepción Visual/fisiología
12.
J Cogn Neurosci ; 25(3): 484-502, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23163410

RESUMEN

When a word is preceded by a supportive context such as a semantically associated word or a strongly constraining sentence frame, the N400 component of the ERP is reduced in amplitude. An ongoing debate is the degree to which this reduction reflects a passive spread of activation across long-term semantic memory representations as opposed to specific predictions about upcoming input. We addressed this question by embedding semantically associated prime-target pairs within an experimental context that encouraged prediction to a greater or lesser degree. The proportion of related items was used to manipulate the predictive validity of the prime for the target while holding semantic association constant. A semantic category probe detection task was used to encourage semantic processing and to preclude the need for a motor response on the trials of interest. A larger N400 reduction to associated targets was observed in the high than the low relatedness proportion condition, consistent with the hypothesis that predictions about upcoming stimuli make a substantial contribution to the N400 effect. We also observed an earlier priming effect (205-240 msec) in the high-proportion condition, which may reflect facilitation because of form-based prediction. In summary, the results suggest that predictability modulates N400 amplitude to a greater degree than the semantic content of the context.


Asunto(s)
Electroencefalografía/métodos , Potenciales Evocados/fisiología , Semántica , Adulto , Electroencefalografía/instrumentación , Medidas del Movimiento Ocular , Femenino , Humanos , Masculino , Memoria/fisiología , Psicolingüística/métodos , Desempeño Psicomotor/fisiología , Memoria Implícita/fisiología , Adulto Joven
13.
Cogn Affect Behav Neurosci ; 13(3): 473-90, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23559312

RESUMEN

Words that are semantically congruous with their preceding discourse context are easier to process than words that are semantically incongruous with their context. This facilitation of semantic processing is reflected by an attenuation of the N400 event-related potential (ERP). We asked whether this was true of emotional words in emotional contexts where discourse congruity was conferred through emotional valence. ERPs were measured as 24 participants read two-sentence scenarios with critical words that varied by emotion (pleasant, unpleasant, or neutral) and congruity (congruous or incongruous). Semantic predictability, constraint, and plausibility were comparable across the neutral and emotional scenarios. As expected, the N400 was smaller to neutral words that were semantically congruous (vs. incongruous) with their neutral discourse context. No such N400 congruity effect was observed on emotional words following emotional discourse contexts. Rather, the amplitude of the N400 was small to all emotional words (pleasant and unpleasant), regardless of whether their emotional valence was congruous with the valence of their emotional discourse context. However, consistent with previous studies, the emotional words produced a larger late positivity than did the neutral words. These data suggest that comprehenders bypassed deep semantic processing of valence-incongruous emotional words within the N400 time window, moving rapidly on to evaluate the words' motivational significance.


Asunto(s)
Emociones/fisiología , Potenciales Evocados/fisiología , Semántica , Adolescente , Adulto , Electroencefalografía/métodos , Femenino , Humanos , Masculino , Motivación , Lectura , Adulto Joven
14.
Psychon Bull Rev ; 2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-37783897

RESUMEN

During language comprehension, the processing of each incoming word is facilitated in proportion to its predictability. Here, we asked whether anticipated upcoming linguistic information is actually pre-activated before new bottom-up input becomes available, and if so, whether this pre-activation is limited to the level of semantic features, or whether extends to representations of individual word-forms (orthography/phonology). We carried out Representational Similarity Analysis on EEG data while participants read highly constraining sentences. Prior to the onset of the expected target words, sentence pairs predicting semantically related words (financial "bank" - "loan") and form-related words (financial "bank" - river "bank") produced more similar neural patterns than pairs predicting unrelated words ("bank" - "lesson"). This provides direct neural evidence for item-specific semantic and form predictive pre-activation. Moreover, the semantic pre-activation effect preceded the form pre-activation effect, suggesting that top-down pre-activation is propagated from higher to lower levels of the linguistic hierarchy over time.

15.
Cognition ; 241: 105602, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37716311

RESUMEN

To comprehend language, we continually use prior context to pre-activate expected upcoming information, resulting in facilitated processing of incoming words that confirm these predictions. But what are the consequences of disconfirming prior predictions? To address this question, most previous studies have examined unpredictable words appearing in contexts that constrain strongly for a single continuation. However, during natural language processing, it is far more common to encounter contexts that constrain for multiple potential continuations, each with some probability. Here, we ask whether and how pre-activating both higher and lower probability alternatives influences the processing of the lower probability incoming word. One possibility is that, similar to language production, there is continuous pressure to select the higher-probability pre-activated alternative through competitive inhibition. During comprehension, this would result in relative costs in processing the lower probability target. A second possibility is that if the two pre-activated alternatives share semantic features, they mutually enhance each other's pre-activation. This would result in greater facilitation in processing the lower probability target. To distinguish between these accounts, we recorded ERPs as participants read three-sentence scenarios that constrained either for a single word or for two potential continuations - a higher probability expected candidate and a lower probability second-best candidate. We found no evidence that competitive pre-activation between the expected and second-best candidates resulted in costs in processing the second-best target, either during lexico-semantic processing (indexed by the N400) or at later stages of processing (indexed by a later frontal positivity). Instead, we found only benefits of pre-activating multiple alternatives, with evidence of enhanced graded facilitation on lower-probability targets that were semantically related to a higher-probability pre-activated alternative. These findings are consistent with a previous eye-tracking study by Luke and Christianson (2016, Cogn Psychol) using corpus-based materials. They have significant theoretical implications for models of predictive language processing, indicating that routine graded prediction in language comprehension does not operate through the same competitive mechanisms that are engaged in language production. Instead, our results align more closely with hierarchical probabilistic accounts of language comprehension, such as predictive coding.


Asunto(s)
Electroencefalografía , Potenciales Evocados , Humanos , Masculino , Femenino , Potenciales Evocados/fisiología , Comprensión/fisiología , Amigos , Lenguaje , Semántica
16.
Schizophr Bull ; 49(Suppl_2): S86-S92, 2023 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-36946526

RESUMEN

This workshop summary on natural language processing (NLP) markers for psychosis and other psychiatric disorders presents some of the clinical and research issues that NLP markers might address and some of the activities needed to move in that direction. We propose that the optimal development of NLP markers would occur in the context of research efforts to map out the underlying mechanisms of psychosis and other disorders. In this workshop, we identified some of the challenges to be addressed in developing and implementing NLP markers-based Clinical Decision Support Systems (CDSSs) in psychiatric practice, especially with respect to psychosis. Of note, a CDSS is meant to enhance decision-making by clinicians by providing additional relevant information primarily through software (although CDSSs are not without risks). In psychiatry, a field that relies on subjective clinical ratings that condense rich temporal behavioral information, the inclusion of computational quantitative NLP markers can plausibly lead to operationalized decision models in place of idiosyncratic ones, although ethical issues must always be paramount.


Asunto(s)
Sistemas de Apoyo a Decisiones Clínicas , Trastornos Mentales , Trastornos Psicóticos , Humanos , Procesamiento de Lenguaje Natural , Lingüística , Trastornos Psicóticos/diagnóstico
17.
Neuroimage ; 62(1): 562-74, 2012 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-22584232

RESUMEN

Accurately communicating self-relevant and emotional information is a vital function of language, but we have little idea about how these factors impact normal discourse comprehension. In an event-related potential (ERP) study, we fully crossed self-relevance and emotion in a discourse context. Two-sentence social vignettes were presented either in the third or the second person (previous work has shown that this influences the perspective from which mental models are built). ERPs were time-locked to a critical word toward the end of the second sentence which was pleasant, neutral, or unpleasant (e.g., A man knocks on Sandra's/your hotel room door. She/You see(s) that he has agift/tray/gunin his hand.). We saw modulation of early components (P1, N1, and P2) by self-relevance, suggesting that a self-relevant context can lead to top-down attentional effects during early stages of visual processing. Unpleasant words evoked a larger late positivity than pleasant words, which evoked a larger positivity than neutral words, indicating that, regardless of self-relevance, emotional words are assessed as motivationally significant, triggering additional or deeper processing at post-lexical stages. Finally, self-relevance and emotion interacted on the late positivity: a larger late positivity was evoked by neutral words in self-relevant, but not in non-self-relevant, contexts. This may reflect prolonged attempts to disambiguate the emotional valence of ambiguous stimuli that are relevant to the self. More broadly, our findings suggest that the assessment of emotion and self-relevance are not independent, but rather that they interactively influence one another during word-by-word language comprehension.


Asunto(s)
Mapeo Encefálico/métodos , Encéfalo/fisiología , Comunicación , Emociones/fisiología , Potenciales Evocados/fisiología , Autoevaluación (Psicología) , Femenino , Humanos , Masculino , Adulto Joven
18.
Cogn Psychol ; 65(1): 1-38, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22387723

RESUMEN

Just as syntax differentiates coherent sentences from scrambled word strings, the comprehension of sequential images must also use a cognitive system to distinguish coherent narrative sequences from random strings of images. We conducted experiments analogous to two classic studies of language processing to examine the contributions of narrative structure and semantic relatedness to processing sequential images. We compared four types of comic strips: (1) Normal sequences with both structure and meaning, (2) Semantic Only sequences (in which the panels were related to a common semantic theme, but had no narrative structure), (3) Structural Only sequences (narrative structure but no semantic relatedness), and (4) Scrambled sequences of randomly-ordered panels. In Experiment 1, participants monitored for target panels in sequences presented panel-by-panel. Reaction times were slowest to panels in Scrambled sequences, intermediate in both Structural Only and Semantic Only sequences, and fastest in Normal sequences. This suggests that both semantic relatedness and narrative structure offer advantages to processing. Experiment 2 measured ERPs to all panels across the whole sequence. The N300/N400 was largest to panels in both the Scrambled and Structural Only sequences, intermediate in Semantic Only sequences and smallest in the Normal sequences. This implies that a combination of narrative structure and semantic relatedness can facilitate semantic processing of upcoming panels (as reflected by the N300/N400). Also, panels in the Scrambled sequences evoked a larger left-lateralized anterior negativity than panels in the Structural Only sequences. This localized effect was distinct from the N300/N400, and appeared despite the fact that these two sequence types were matched on local semantic relatedness between individual panels. These findings suggest that sequential image comprehension uses a narrative structure that may be independent of semantic relatedness. Altogether, we argue that the comprehension of visual narrative is guided by an interaction between structure and meaning.


Asunto(s)
Comprensión , Narración , Percepción Visual , Adulto , Dibujos Animados como Asunto , Femenino , Humanos , Masculino , Semántica
19.
J Exp Psychol Gen ; 151(7): 1502-1519, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34843366

RESUMEN

The ability to detect and respond to linguistic errors is critical for successful reading comprehension, but these skills can vary considerably across readers. In the current study, healthy adults (age 18-35) read short discourse scenarios for comprehension while monitoring for the presence of semantic anomalies. Using a factor analytic approach, we examined if performance in nonlinguistic conflict monitoring tasks (Stroop, AX-CPT) would predict individual differences in neural and behavioral measures of linguistic error processing. Consistent with this hypothesis, domain-general conflict monitoring predicted both readers' end-of-trial acceptability judgments and the amplitude of a late neural response (the P600) evoked by linguistic anomalies. The influence on the P600 was nonlinear, suggesting that online neural responses to linguistic errors are influenced by both the effectiveness and efficiency of domain-general conflict monitoring. These relationships were also highly specific and remained after controlling for variability in working memory capacity and verbal knowledge. Finally, we found that domain-general conflict monitoring also predicted individual variability in measures of reading comprehension, and that this relationship was partially mediated by behavioral measures of linguistic error detection. These findings inform our understanding of the role of domain-general executive functions in reading comprehension, with potential implications for the diagnosis and treatment of language impairments. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Asunto(s)
Comprensión , Lectura , Adolescente , Adulto , Comprensión/fisiología , Humanos , Lingüística , Memoria a Corto Plazo/fisiología , Semántica , Adulto Joven
20.
J Exp Psychol Gen ; 151(7): 1556-1572, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34843363

RESUMEN

According to several influential theoretical frameworks, phonological deficits in dyslexia result from reduced sensitivity to acoustic cues that are essential for the development of robust phonemic representations. Some accounts suggest that these deficits arise from impairments in rapid auditory adaptation processes that are either speech-specific or domain-general. Here, we examined the specificity of auditory adaptation deficits in dyslexia using a nonlinguistic tone anchoring (adaptation) task and a linguistic selective adaptation task in children and adults with and without dyslexia. Children and adults with dyslexia had elevated tone-frequency discrimination thresholds, but both groups benefited from anchoring to repeated stimuli to the same extent as typical readers. Additionally, although both dyslexia groups had overall reduced accuracy for speech sound identification, only the child group had reduced categorical perception for speech. Across both age groups, individuals with dyslexia had reduced perceptual adaptation to speech. These results highlight broad auditory perceptual deficits across development in individuals with dyslexia for both linguistic and nonlinguistic domains, but speech-specific adaptation deficits. Finally, mediation models in children and adults revealed that the causal pathways from basic perception and adaptation to phonological awareness through speech categorization were not significant. Thus, rather than having causal effects, perceptual deficits may co-occur with the phonological deficits in dyslexia across development. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Asunto(s)
Dislexia , Percepción del Habla , Adulto , Niño , Señales (Psicología) , Humanos , Fonética , Habla
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