RESUMO
Crossmodal correspondences (CMCs) refer to associations between seemingly arbitrary stimulus features in different sensory modalities. Pitchsize correspondences refer to the strong association of e.g., small objects with high pitches. Pitchelevation correspondences refer to the strong association of e.g., visuospatial elevated objects with high pitches. We used functional magnetic resonance imaging (fMRI) to study the neural components, which underlie the CMCs in pitchsize and spatial pitchelevation. This study focuses on answering the question of whether or not different CMCs are driven by similar neural mechanisms. The comparison of congruent against incongruent trials allows the estimation of CMC effects across different CMCs. The analysis of the measured neural activity in different CMCs strongly pointed toward different mechanisms which are involved in the processing of pitchsize and pitchelevation correspondences. Differential, whole brain effects were observed within the superior parietal lobule (SPL), cerebellum and Heschls' gyrus (HG). Further, the angular gyrus (AnG), the intraparietal sulcus (IPS) and anterior cingulate cortex (ACC) were engaged in processing the CMCs but showed different effects for processing congruent compared to incongruent stimulus presentations. Within pitchsize significant effects in the AnG and ACC were found for congruent stimulus presentations whereas for pitchelevation, significant effects in the ACC and IPS were found for incongruent stimulus presentations. In summary, the present results indicated differential neural processing in different simple audiovisual CMCs.
Assuntos
Estimulação Acústica , Mapeamento Encefálico , Encéfalo , Imageamento por Ressonância Magnética , Humanos , Masculino , Imageamento por Ressonância Magnética/métodos , Feminino , Adulto , Adulto Jovem , Estimulação Acústica/métodos , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Percepção da Altura Sonora/fisiologia , Estimulação Luminosa/métodos , Percepção Visual/fisiologiaRESUMO
Music is omnipresent in daily life and may interact with critical cognitive processes including memory. Despite music's presence during diverse daily activities including studying, commuting, or working, existing literature has yielded mixed results as to whether music improves or impairs memory for information experienced in parallel. To elucidate how music memory and its predictive structure modulate the encoding of novel information, we developed a cross-modal sequence learning task during which participants acquired sequences of abstract shapes accompanied with paired music. Our goal was to investigate whether familiar and structurally regular music could provide a "temporal schema" (rooted in the organized and hierarchical structure of music) to enhance the acquisition of parallel temporally-ordered visual information. Results revealed a complex interplay between music familiarity and music structural regularity in learning paired visual sequences. Notably, compared to a control condition, listening to well-learned, regularly-structured music (music with high predictability) significantly facilitated visual sequence encoding, yielding quicker learning and retrieval speed. Conversely, learned but irregular music (where music memory violated musical syntax) significantly impaired sequence encoding. While those findings supported our mechanistic framework, intriguingly, unlearned irregular music-characterized by the lowest predictability-also demonstrated memory enhancement. In conclusion, this study demonstrates that concurrent music can modulate visual sequence learning, and the effect varies depending on the interaction between both music familiarity and regularity, offering insights into potential applications for enhancing human memory.
Assuntos
Música , Reconhecimento Psicológico , Humanos , Música/psicologia , Feminino , Masculino , Reconhecimento Psicológico/fisiologia , Adulto Jovem , Adulto , Aprendizagem/fisiologia , Percepção Auditiva/fisiologia , Percepção Visual/fisiologia , Memória/fisiologia , Estimulação Acústica , Estimulação LuminosaRESUMO
Film cognition explores the influence of cinematic elements, such as editing and film color, on viewers' perception. The Kuleshov effect, a famous example of how editing influences viewers' emotional perception, was initially proposed to support montage theory through the Kuleshov experiment. This effect, which has since been recognized as a manifestation of point-of-view (POV) editing practices, posits that the emotional interpretation of neutral facial expressions is influenced by the accompanying emotional scene in a face-scene-face sequence. However, concerns persist regarding the validity of previous studies, often employing inauthentic film materials like static images, leaving the question of its existence in authentic films unanswered. This study addresses these concerns by utilizing authentic films in two experiments. In Experiment 1, multiple film clips were captured under the guidance of a professional film director and seamlessly integrated into authentic film sequences. 59 participants viewed these face-scene-face film sequences and were tasked with rating the valence and emotional intensity of neutral faces. The findings revealed that the accompanying fearful or happy scenes significantly influence the interpretation of emotion on neutral faces, eliciting perceptions of negative or positive emotions from the neutral face. These results affirm the existence of the Kuleshov effect within authentic films. In Experiment 2, 31 participants rated the valence and arousal of neutral faces while undergoing functional magnetic resonance imaging (fMRI). The behavioral results confirm the Kuleshov effect in the MRI scanner, while the neural data identify neural correlates that support its existence at the neural level. These correlates include the cuneus, precuneus, hippocampus, parahippocampal gyrus, post cingulate gyrus, orbitofrontal cortex, fusiform gyrus, and insula. These findings also underscore the contextual framing inherent in the Kuleshov effect. Overall, the study integrates film theory and cognitive neuroscience experiments, providing robust evidence supporting the existence of the Kuleshov effect through both subjective ratings and objective neuroimaging measurements. This research also contributes to a deeper understanding of the impact of film editing on viewers' emotional perception from the contemporary POV editing practices and neurocinematic perspective, advancing the knowledge of film cognition.
Assuntos
Emoções , Expressão Facial , Imageamento por Ressonância Magnética , Filmes Cinematográficos , Humanos , Emoções/fisiologia , Feminino , Masculino , Adulto , Adulto Jovem , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Estimulação Luminosa , Percepção Visual/fisiologiaRESUMO
Individuals exhibit massive variability in general cognitive skills that affect language processing. This variability is partly developmental. Here, we recruited a large sample of participants (N = 487), ranging from 9 to 90 years of age, and examined the involvement of nonverbal processing speed (assessed using visual and auditory reaction time tasks) and working memory (assessed using forward and backward Digit Span tasks) in a visual world task. Participants saw two objects on the screen and heard a sentence that referred to one of them. In half of the sentences, the target object could be predicted based on verb-selectional restrictions. We observed evidence for anticipatory processing on predictable compared to non-predictable trials. Visual and auditory processing speed had main effects on sentence comprehension and facilitated predictive processing, as evidenced by an interaction. We observed only weak evidence for the involvement of working memory in predictive sentence comprehension. Age had a nonlinear main effect (younger adults responded faster than children and older adults), but it did not differentially modulate predictive and non-predictive processing, nor did it modulate the involvement of processing speed and working memory. Our results contribute to delineating the cognitive skills that are involved in language-vision interactions.
Assuntos
Cognição , Compreensão , Individualidade , Memória de Curto Prazo , Tempo de Reação , Humanos , Adulto , Criança , Feminino , Masculino , Adolescente , Compreensão/fisiologia , Cognição/fisiologia , Pessoa de Meia-Idade , Idoso , Memória de Curto Prazo/fisiologia , Adulto Jovem , Idoso de 80 Anos ou mais , Tempo de Reação/fisiologia , Idioma , Percepção Visual/fisiologia , LinguísticaRESUMO
Speech perception requires the binding of spatiotemporally disjoint auditory-visual cues. The corresponding brain network-level information processing can be characterized by two complementary mechanisms: functional segregation which refers to the localization of processing in either isolated or distributed modules across the brain, and integration which pertains to cooperation among relevant functional modules. Here, we demonstrate using functional magnetic resonance imaging recordings that subjective perceptual experience of multisensory speech stimuli, real and illusory, are represented in differential states of segregation-integration. We controlled the inter-subject variability of illusory/cross-modal perception parametrically, by introducing temporal lags in the incongruent auditory-visual articulations of speech sounds within the McGurk paradigm. The states of segregation-integration balance were captured using two alternative computational approaches. First, the module responsible for cross-modal binding of sensory signals defined as the perceptual binding network (PBN) was identified using standardized parametric statistical approaches and their temporal correlations with all other brain areas were computed. With increasing illusory perception, the majority of the nodes of PBN showed decreased cooperation with the rest of the brain, reflecting states of high segregation but reduced global integration. Second, using graph theoretic measures, the altered patterns of segregation-integration were cross-validated.
Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Percepção da Fala , Percepção Visual , Humanos , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Masculino , Feminino , Adulto , Adulto Jovem , Percepção da Fala/fisiologia , Percepção Visual/fisiologia , Mapeamento Encefálico , Estimulação Acústica , Rede Nervosa/fisiologia , Rede Nervosa/diagnóstico por imagem , Estimulação Luminosa/métodos , Ilusões/fisiologia , Vias Neurais/fisiologia , Percepção Auditiva/fisiologiaRESUMO
BACKGROUND: Cannabis is the most widely used psychoactive drug in the United States. While multiple studies have associated acute cannabis consumption with alterations in cognitive function (e.g., visual and spatial attention), far less is known regarding the effects of chronic consumption on the neural dynamics supporting these cognitive functions. METHODS: We used magnetoencephalography (MEG) and an established visuospatial processing task to elicit multi-spectral neuronal responses in 44 regular cannabis users and 53 demographically matched non-user controls. To examine the effects of chronic cannabis use on the oscillatory dynamics underlying visuospatial processing, neural responses were imaged using a time-frequency resolved beamformer and compared across groups. RESULTS: Neuronal oscillations serving visuospatial processing were identified in the theta (4-8 Hz), alpha (8-14 Hz), and gamma range (56-76 Hz), and these were imaged and examined for group differences. Our key results indicated that users exhibited weaker theta oscillations in occipital and cerebellar regions and weaker gamma responses in the left temporal cortices compared to non-users. Lastly, alpha oscillations did not differ, but alpha connectivity among higher-order attention areas was weaker in cannabis users relative to non-users and correlated with performance. CONCLUSIONS: Overall, these results suggest that chronic cannabis users have alterations in the oscillatory dynamics and neural connectivity serving visuospatial attention. Such alterations were observed across multiple cortical areas critical for higher-order processing and may reflect compensatory activity and/or the initial emergence of aberrant dynamics. Future work is needed to fully understand the implications of altered multispectral oscillations and neural connectivity in cannabis users.
Assuntos
Atenção , Magnetoencefalografia , Humanos , Masculino , Feminino , Adulto , Adulto Jovem , Atenção/efeitos dos fármacos , Atenção/fisiologia , Percepção Visual/fisiologia , Percepção Visual/efeitos dos fármacos , Encéfalo/fisiopatologia , Encéfalo/efeitos dos fármacos , Cognição/efeitos dos fármacos , Cognição/fisiologiaRESUMO
The Corsi (block-tapping) paradigm is a classic and well-established visuospatial working memory task in humans involving internal computations (memorizing of item sequences, organizing and updating the memorandum, and recall processes), as well as both overt and covert shifts of attention to facilitate rehearsal, serving to maintain the Corsi sequences during the retention phase. Here, we introduce a novel digital version of a Corsi task in which i) the difficulty of the memorandum (using sequence lengths ranging from 3 to 8) was controlled, ii) the execution of overt and/or covert attention as well as the visuospatial working memory load during the retention phase was manipulated, and iii) shifts of attention were quantified in all experimental phases. With this, we present behavioral data that demonstrate, characterize, and classify the individual effects of overt and covert strategies used as a means of encoding and rehearsal. In a full within-subject design, we tested 28 participants who had to solve three different Corsi conditions. While in condition A neither of the two strategies were restricted, in condition B the overt and in condition C the overt as well as the covert strategies were suppressed. Analyzing Corsi span, (eye) exploration index, and pupil size (change), data clearly show a continuum between overt and covert strategies over all participants (indicating inter-individual variability). Further, all participants showed stable strategy choice (indicating intra-individual stability), meaning that the preferred strategy was maintained in all three conditions, phases, and sequence lengths of the experiment.
Assuntos
Atenção , Memória de Curto Prazo , Humanos , Masculino , Memória de Curto Prazo/fisiologia , Feminino , Atenção/fisiologia , Adulto , Adulto Jovem , Estimulação Luminosa/métodos , Percepção Espacial/fisiologia , Desempenho Psicomotor/fisiologia , Percepção Visual/fisiologiaRESUMO
BACKGROUND: Altered sensory processing in migraine has been demonstrated by several studies in unimodal, and especially visual, tasks. While there is some limited evidence hinting at potential alterations in multisensory processing among migraine sufferers, this aspect remains relatively unexplored. This study investigated the interictal cognitive performance of migraine patients without aura compared to matched controls, focusing on associative learning, recall, and transfer abilities through the Sound-Face Test, an audiovisual test based on the principles of the Rutgers Acquired Equivalence Test. MATERIALS AND METHODS: The performance of 42 volunteering migraine patients was compared to the data of 42 matched controls, selected from a database of healthy volunteers who had taken the test earlier. The study aimed to compare the groups' performance in learning, recall, and the ability to transfer learned associations. RESULTS: Migraine patients demonstrated significantly superior associative learning as compared to controls, requiring fewer trials, and making fewer errors during the acquisition phase. However, no significant differences were observed in retrieval error ratios, generalization error ratios, or reaction times between migraine patients and controls in later stages of the test. CONCLUSION: The results of our study support those of previous investigations, which concluded that multisensory processing exhibits a unique pattern in migraine. The specific finding that associative audiovisual pair learning is more effective in adult migraine patients than in matched controls is unexpected. If the phenomenon is not an artifact, it may be assumed to be a combined result of the hypersensitivity present in migraine and the sensory threshold-lowering effect of multisensory integration.
Assuntos
Aprendizagem por Associação , Enxaqueca sem Aura , Humanos , Adulto , Feminino , Masculino , Aprendizagem por Associação/fisiologia , Enxaqueca sem Aura/fisiopatologia , Adulto Jovem , Percepção Visual/fisiologia , Percepção Auditiva/fisiologia , Pessoa de Meia-Idade , Estimulação Luminosa/métodos , Estimulação Acústica/métodosRESUMO
Tools enable humans to extend their sensing abilities beyond the natural limits of their hands, allowing them to sense objects as if they were using their hands directly. The similarities between direct hand interactions with objects (hand-based sensing) and the ability to extend sensory information processing beyond the hand (tool-mediated sensing) entail the existence of comparable processes for integrating tool- and hand-sensed information with vision, raising the question of whether tools support vision in bimanual object manipulations. Here, we investigated participants' performance while grasping objects either held with a tool or with their hand and compared these conditions with visually guided grasping (Experiment 1). By measuring reaction time, peak velocity, and peak of grip aperture, we found that actions were initiated earlier and performed with a smaller peak grip aperture when the object was seen and held with the tool or the contralateral hand compared to when it was only seen. Thus, tool-mediated sensing effectively supports vision in multisensory grasping and, even more intriguingly, resembles hand-based sensing. We excluded that results were due to the force exerted on the tool's handle (Experiment 2). Additionally, as for hand-based sensing, we found evidence that the tool supports vision by mainly providing object positional information (Experiment 3). Thus, integrating the tool-sensed position of the object with vision is sufficient to promote a multisensory advantage in grasping. Our findings indicate that multisensory integration mechanisms significantly improve grasping actions and fine-tune contralateral hand movements even when object information is only indirectly sensed through a tool. (PsycInfo Database Record (c) 2024 APA, all rights reserved).
Assuntos
Força da Mão , Mãos , Desempenho Psicomotor , Percepção Visual , Humanos , Masculino , Feminino , Adulto , Desempenho Psicomotor/fisiologia , Força da Mão/fisiologia , Adulto Jovem , Percepção Visual/fisiologia , Mãos/fisiologia , Tempo de Reação/fisiologiaRESUMO
White matter (WM) functional activity has been reliably detected through functional magnetic resonance imaging (fMRI). Previous studies have primarily examined WM bundles as unified entities, thereby obscuring the functional heterogeneity inherent within these bundles. Here, for the first time, we investigate the function of sub-bundles of a prototypical visual WM tract-the optic radiation (OR). We use the 7T retinotopy dataset from the Human Connectome Project (HCP) to reconstruct OR and further subdivide the OR into sub-bundles based on the fiber's termination in the primary visual cortex (V1). The population receptive field (pRF) model is then applied to evaluate the retinotopic properties of these sub-bundles, and the consistency of the pRF properties of sub-bundles with those of V1 subfields is evaluated. Furthermore, we utilize the HCP working memory dataset to evaluate the activations of the foveal and peripheral OR sub-bundles, along with LGN and V1 subfields, during 0-back and 2-back tasks. We then evaluate differences in 2bk-0bk contrast between foveal and peripheral sub-bundles (or subfields), and further examine potential relationships between 2bk-0bk contrast and 2-back task d-prime. The results show that the pRF properties of OR sub-bundles exhibit standard retinotopic properties and are typically similar to the properties of V1 subfields. Notably, activations during the 2-back task consistently surpass those under the 0-back task across foveal and peripheral OR sub-bundles, as well as LGN and V1 subfields. The foveal V1 displays significantly higher 2bk-0bk contrast than peripheral V1. The 2-back task d-prime shows strong correlations with 2bk-0bk contrast for foveal and peripheral OR fibers. These findings demonstrate that the blood oxygen level-dependent (BOLD) signals of OR sub-bundles encode high-fidelity visual information, underscoring the feasibility of assessing WM functional activity at the sub-bundle level. Additionally, the study highlights the role of OR in the top-down processes of visual working memory beyond the bottom-up processes for visual information transmission. Conclusively, this study innovatively proposes a novel paradigm for analyzing WM fiber tracts at the individual sub-bundle level and expands understanding of OR function.
Assuntos
Conectoma , Imageamento por Ressonância Magnética , Memória de Curto Prazo , Vias Visuais , Humanos , Memória de Curto Prazo/fisiologia , Conectoma/métodos , Vias Visuais/fisiologia , Vias Visuais/diagnóstico por imagem , Adulto , Masculino , Feminino , Percepção Visual/fisiologia , Substância Branca/diagnóstico por imagem , Substância Branca/fisiologia , Substância Branca/anatomia & histologia , Córtex Visual Primário/fisiologia , Córtex Visual Primário/diagnóstico por imagem , Corpos Geniculados/fisiologia , Corpos Geniculados/diagnóstico por imagem , Adulto Jovem , Córtex Visual/fisiologia , Córtex Visual/diagnóstico por imagemRESUMO
Perceptual decisions should depend on sensory evidence. However, such decisions are also influenced by past choices and outcomes. These choice history biases may reflect advantageous strategies to exploit temporal regularities of natural environments. However, it is unclear whether and how observers can adapt their choice history biases to different temporal regularities, to exploit the multitude of temporal correlations that exist in nature. Here, we show that male mice adapt their perceptual choice history biases to different temporal regularities of visual stimuli. This adaptation was slow, evolving over hundreds of trials across several days. It occurred alongside a fast non-adaptive choice history bias, limited to a few trials. Both fast and slow trial history effects are well captured by a normative reinforcement learning algorithm with multi-trial belief states, comprising both current trial sensory and previous trial memory states. We demonstrate that dorsal striatal dopamine tracks predictions of the model and behavior, suggesting that striatal dopamine reports reward predictions associated with adaptive choice history biases. Our results reveal the adaptive nature of perceptual choice history biases and shed light on their underlying computational principles and neural correlates.
Assuntos
Comportamento de Escolha , Corpo Estriado , Dopamina , Animais , Masculino , Dopamina/metabolismo , Camundongos , Corpo Estriado/metabolismo , Corpo Estriado/fisiologia , Comportamento de Escolha/fisiologia , Camundongos Endogâmicos C57BL , Tomada de Decisões/fisiologia , Recompensa , Estimulação Luminosa , Percepção Visual/fisiologia , Reforço PsicológicoRESUMO
Visual recognition is largely realized through neurons in the ventral stream, though recently, studies have suggested that ventrolateral prefrontal cortex (vlPFC) is also important for visual processing. While it is hypothesized that sensory and cognitive processes are integrated in vlPFC neurons, it is not clear how this mechanism benefits vision, or even if vlPFC neurons have properties essential for computations in visual cortex implemented via recurrence. Here, we investigated if vlPFC neurons in two male monkeys had functions comparable to visual cortex, including receptive fields, image selectivity, and the capacity to synthesize highly activating stimuli using generative networks. We found a subset of vlPFC sites show all properties, suggesting subpopulations of vlPFC neurons encode statistics about the world. Further, these vlPFC sites may be anatomically clustered, consistent with fMRI-identified functional organization. Our findings suggest that stable visual encoding in vlPFC may be a necessary condition for local and brain-wide computations.
Assuntos
Macaca mulatta , Imageamento por Ressonância Magnética , Neurônios , Córtex Pré-Frontal , Córtex Visual , Córtex Pré-Frontal/fisiologia , Córtex Pré-Frontal/citologia , Córtex Pré-Frontal/diagnóstico por imagem , Animais , Masculino , Córtex Visual/fisiologia , Córtex Visual/citologia , Córtex Visual/diagnóstico por imagem , Neurônios/fisiologia , Estimulação Luminosa , Percepção Visual/fisiologia , Mapeamento EncefálicoRESUMO
The label-feedback hypothesis states that language can modulate visual processing. In particular, hearing or reading aloud target names (labels) speeds up performance in visual search tasks by facilitating target detection and such advantage is often measured against a condition where the target name is shown visually (i.e. via the same modality as the search task). The current study conceptually complements and expands previous investigations. The effect of a multimodal label presentation (i.e., an audio+visual, AV, priming label) in a visual search task is compared to that of a multimodal (i.e. white noise+visual, NV, label) and two unimodal (i.e. audio, A, label or visual, V, label) control conditions. The name of a category (i.e. a label at the superordinate level) is used as a cue, instead of the more commonly used target name (a basic level label), with targets belonging to one of three categories: garments, improper weapons, and proper weapons. These categories vary for their structure, improper weapons being an ad hoc category (i.e. context-dependent), unlike proper weapons and garments. The preregistered analysis shows an overall facilitation of visual search performance in the AV condition compared to the NV condition, confirming that the label-feedback effect may not be explained away by the effects of multimodal stimulation only and that it extends to superordinate labels. Moreover, exploratory analyses show that such facilitation is driven by the garments and proper weapons categories, rather than improper weapons. Thus, the superordinate label-feedback effect is modulated by the structural properties of a category. These findings are consistent with the idea that the AV condition prompts an "up-regulation" of the label, a requirement for enhancing the label's beneficial effects, but not when the label refers to an ad hoc category. They also highlight the peculiar status of the category of improper weapons and set it apart from that of proper weapons.
Assuntos
Percepção Visual , Humanos , Feminino , Percepção Visual/fisiologia , Masculino , Adulto , Adulto Jovem , Tempo de Reação/fisiologia , Estimulação Luminosa , Idioma , LeituraRESUMO
Across the visual periphery, perceptual and metacognitive abilities differ depending on the locus of visual attention, the location of peripheral stimulus presentation, the task design, and many other factors. In this investigation, we aimed to illuminate the relationship between attention and eccentricity in the visual periphery by estimating perceptual sensitivity, metacognitive sensitivity, and response biases across the visual field. In a 2AFC detection task, participants were asked to determine whether a signal was present or absent at one of eight peripheral locations (±10°, 20°, 30°, and 40°), using either a valid or invalid attentional cue. As expected, results revealed that perceptual sensitivity declined with eccentricity and was modulated by attention, with higher sensitivity on validly cued trials. Furthermore, a significant main effect of eccentricity on response bias emerged, with variable (but relatively unbiased) c'a values from 10° to 30°, and conservative c'a values at 40°. Regarding metacognitive sensitivity, significant main effects of attention and eccentricity were found, with metacognitive sensitivity decreasing with eccentricity, and decreasing in the invalid cue condition. Interestingly, metacognitive efficiency, as measured by the ratio of meta-d'a/d'a, was not modulated by attention or eccentricity. Overall, these findings demonstrate (1) that in some circumstances, observers have surprisingly robust metacognitive insights into how performance changes across the visual field and (2) that the periphery may be subject to variable detection biases that are contingent on the exact location in peripheral space.
Assuntos
Atenção , Sinais (Psicologia) , Metacognição , Estimulação Luminosa , Campos Visuais , Humanos , Campos Visuais/fisiologia , Atenção/fisiologia , Masculino , Adulto Jovem , Feminino , Adulto , Estimulação Luminosa/métodos , Metacognição/fisiologia , Percepção Visual/fisiologiaRESUMO
Contextual cueing is a phenomenon of visual statistical learning observed in visual search tasks. Previous research has found that the degree of deviation of items from its centroid, known as variability, determines the extent of generalization for that repeated scene. Introducing variability increases dissimilarity between multiple occurrences of the same repeated layout significantly. However, current theories do not explain the mechanisms that help to overcome this dissimilarity during contextual cue learning. We propose that the cognitive system initially abstracts specific scenes into scene layouts through an automatic clustering unrelated to specific repeated scenes, and subsequently uses these abstracted scene layouts for contextual cue learning. Experiment 1 indicates that introducing greater variability in search scenes leads to a hindering in the contextual cue learning. Experiment 2 further establishes that conducting extensive visual searches involving spatial variability in entirely novel scenes facilitates subsequent contextual cue learning involving corresponding scene variability, confirming that learning clustering knowledge precedes the contextual cue learning and is independent of specific repeated scenes. Overall, this study demonstrates the existence of multiple levels of learning in visual statistical learning, where item-level learning can serve as material for layout-level learning, and the generalization reflects the constraining role of item-level knowledge on layout-level knowledge.
Assuntos
Sinais (Psicologia) , Humanos , Estimulação Luminosa/métodos , Aprendizagem/fisiologia , Adulto Jovem , Masculino , Feminino , Reconhecimento Visual de Modelos/fisiologia , Percepção Visual/fisiologia , Adulto , Análise por Conglomerados , Atenção/fisiologiaRESUMO
Visual perception involves binding of distinct features into a unified percept. Although traditional theories link feature binding to time-consuming recurrent processes, Holcombe and Cavanagh (2001) demonstrated ultrafast, early binding of features that belong to the same object. The task required binding of orientation and luminance within an exceptionally short presentation time. However, because visual stimuli were presented over multiple presentation cycles, their findings can alternatively be explained by temporal integration over the extended stimulus sequence. Here, we conducted three experiments manipulating the number of presentation cycles. If early binding occurs, one extremely short cycle should be sufficient for feature integration. Conversely, late binding theories predict that successful binding requires substantial time and improves with additional presentation cycles. Our findings indicate that task-relevant binding of features from the same object occurs slowly, supporting late binding theories.
Assuntos
Estimulação Luminosa , Humanos , Estimulação Luminosa/métodos , Fatores de Tempo , Masculino , Adulto Jovem , Adulto , Feminino , Percepção Visual/fisiologia , Orientação/fisiologiaRESUMO
Hand visibility affects motor control, perception, and attention, as visual information is integrated into an internal model of somatomotor control. Spontaneous brain activity, i.e., at rest, in the absence of an active task, is correlated among somatomotor regions that are jointly activated during motor tasks. Recent studies suggest that spontaneous activity patterns not only replay task activation patterns but also maintain a model of the body's and environment's statistical regularities (priors), which may be used to predict upcoming behavior. Here, we test whether spontaneous activity in the human somatomotor cortex as measured using fMRI is modulated by visual stimuli that display hands vs. non-hand stimuli and by the use/action they represent. A multivariate pattern analysis was performed to examine the similarity between spontaneous activity patterns and task-evoked patterns to the presentation of natural hands, robot hands, gloves, or control stimuli (food). In the left somatomotor cortex, we observed a stronger (multivoxel) spatial correlation between resting state activity and natural hand picture patterns compared to other stimuli. No task-rest similarity was found in the visual cortex. Spontaneous activity patterns in somatomotor brain regions code for the visual representation of human hands and their use.
Assuntos
Mapeamento Encefálico , Mãos , Imageamento por Ressonância Magnética , Percepção Visual , Humanos , Mãos/fisiologia , Masculino , Feminino , Adulto , Percepção Visual/fisiologia , Adulto Jovem , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Córtex Motor/fisiologia , Córtex Motor/diagnóstico por imagem , Descanso/fisiologia , Estimulação Luminosa , Córtex Visual/fisiologia , Córtex Visual/diagnóstico por imagemRESUMO
Predictive coding theory suggests the brain anticipates sensory information using prior knowledge. While this theory has been extensively researched within individual sensory modalities, evidence for predictive processing across sensory modalities is limited. Here, we examine how crossmodal knowledge is represented and learned in the brain, by identifying the hierarchical networks underlying crossmodal predictions when information of one sensory modality leads to a prediction in another modality. We record electroencephalogram (EEG) during a crossmodal audiovisual local-global oddball paradigm, in which the predictability of transitions between tones and images are manipulated at both the stimulus and sequence levels. To dissect the complex predictive signals in our EEG data, we employed a model-fitting approach to untangle neural interactions across modalities and hierarchies. The model-fitting result demonstrates that audiovisual integration occurs at both the levels of individual stimulus interactions and multi-stimulus sequences. Furthermore, we identify the spatio-spectro-temporal signatures of prediction-error signals across hierarchies and modalities, and reveal that auditory and visual prediction errors are rapidly redirected to the central-parietal electrodes during learning through alpha-band interactions. Our study suggests a crossmodal predictive coding mechanism where unimodal predictions are processed by distributed brain networks to form crossmodal knowledge.
Assuntos
Percepção Auditiva , Encéfalo , Eletroencefalografia , Percepção Visual , Humanos , Encéfalo/fisiologia , Percepção Auditiva/fisiologia , Percepção Visual/fisiologia , Masculino , Feminino , Adulto , Adulto Jovem , Estimulação Acústica , Estimulação LuminosaRESUMO
This study aimed to examine the effects of a visual praxis-based occupational therapy (VPOT) programme on reading and motor skills for children with developmental dyslexia (DD). Forty-two children were included in the study. Additionally, before VPOT, the Reading-Aloud and Reading-Comprehension Test 2 (ORSRC-2) and the Bruininks-Oseretsky Motor-Proficiency-Test-2-Brief Form (BOT2-BF) were applied to the participants. According to the study design, VPOT was applied to two sessions per week for 8 weeks to group A. During this period, group B was accepted as the control group. At the end of these 8 weeks, evaluation tests were applied to both groups. Then, group A was defined as the control group and Group B as the intervention group, and VPOT was applied to Group B. At the end of another 8 weeks, evaluation tests were applied to both groups for the third time. When the final ORSRC-2 results were examined, VPOT was found to be an effective programme for improving reading skills. Additionally, when the final BOT2-BF results were examined, VPOT was determined to be effective in improving motor skills (p < 0.05). We believe that it is important to carry out comprehensive studies such as the VPOT programme to solve problems in the physical and learning activities of children with DD.
Assuntos
Estudos Cross-Over , Dislexia , Destreza Motora , Terapia Ocupacional , Leitura , Percepção Visual , Humanos , Terapia Ocupacional/métodos , Dislexia/reabilitação , Dislexia/terapia , Criança , Feminino , Masculino , Destreza Motora/fisiologia , Método Simples-Cego , Percepção Visual/fisiologiaRESUMO
It is well known that attention is captured by salient objects or events. The notion that attention is attracted by salience information present in the visual field is also at the heart of many influential models of attention. These models typically posit a hierarchy of saliency, suggesting that attention progresses from the most to the least salient item in the visual field. However, despite the significance of this claim in various models, research on eye movements challenges the idea that search strictly follows this saliency hierarchy. Instead, eye-tracking studies have suggested that saliency information has a transient impact, only influencing the initial saccade toward the most salient object, and only if executed swiftly after display onset. While these findings on overt eye movements are important, they do not address covert attentional processes occurring before a saccade is initiated. In the current series of experiments, we explored whether there was evidence for secondary capture-whether attention could be captured by another salient item after the initial capture episode. To explore this, we utilized displays with multiple distractors of varying levels of saliency. Our primary question was whether two distractors with different saliency levels would disrupt search more than a single, highly salient distractor. Across three experiments, clear evidence emerged indicating that two distractors interfered more with search than a single salient distractor. This observation suggests that following initial capture, secondary capture by the next most salient distractor occurred. These findings collectively support the idea that covert attention traverses the saliency hierarchy. (PsycInfo Database Record (c) 2024 APA, all rights reserved).