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1.
Cognition ; 230: 105291, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36183630

RESUMO

While the human visual system is sensitive to numerosity, the mechanisms that allow perception to extract and represent the number of objects in a scene remains unknown. Prominent theoretical approaches posit that numerosity perception emerges from passive experience with visual scenes throughout development, and that unsupervised deep neural network models mirror all characteristic behavioral features observed in participants. Here, we derive and test a novel prediction: if the visual number sense emerges from exposure to real-world scenes, then the closer a stimulus aligns with the natural statistics of the real world, the better number perception should be. But - in contrast to this prediction - we observe no such advantage (and sometimes even a notable impairment) in number perception for natural scenes compared to artificial dot displays in college-aged adults. These findings are not accounted for by the difficulty in object identification, visual clutter, the parsability of objects from the rest of the scene, or increased occlusion. This pattern of results represents a fundamental challenge to recent models of numerosity perception based in experiential learning of statistical regularities, and instead suggests that the visual number sense is attuned to abstract number of objects, independent of their underlying correlation with non-numeric features. We discuss our results in the context of recent proposals that suggest that object complexity and entropy may play a role in number perception.


Assuntos
Cognição , Percepção Visual , Adulto , Humanos , Adulto Jovem , Redes Neurais de Computação , Reconhecimento Visual de Modelos
2.
J Behav Ther Exp Psychiatry ; 78: 101796, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36435538

RESUMO

BACKGROUND AND OBJECTIVES: Repetition blindness (RB) refers to the difficulty to report repetitions of stimuli visually presented in a rapid list. To date only two studies have examined RB in patients with schizophrenia and the results are not clear-cut. The current study was designed to employ a task with reduced memory load, more trials in each experimental condition, and more participants to obtain a more reliable RB effect. METHODS: A 2x2x3x2 mixed factor repeated measure design was used, with stimulus repetition, lag, and presentation rate as within-subject factors, and group (patient or control) as a between-subject factor. A rapid serial visual presentation (RSVP) procedure was used. Twenty eight inpatients with schizophrenia and 28 healthy controls participated in the experiment. RESULTS: The patient group showed significantly impaired performance when compared tothe control group in every experimental condition. Nevertheless, the patient group demonstrated similar RB effect as the control group. Furthermore, the overall RB effect observed in patients did not relate to their illness severity or psychotic symptoms. Neither was it related to their age or education. LIMITATIONS: It was difficult to match the age and education of the control group to that of the inpatient group. CONCLUSIONS: Patients with schizophrenia performed worse than healthy controls in each experimental condition. Both the control and patient group showed robust RB effect in the short lag with faster rates. In addition, RB effect seemed to be irrelevant to patients' illness severity and clinical symptoms.


Assuntos
Esquizofrenia , Humanos , Esquizofrenia/complicações , Reconhecimento Visual de Modelos
3.
Nat Commun ; 13(1): 6787, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36351907

RESUMO

Although the presence of face patches in primate inferotemporal (IT) cortex is well established, the functional and causal relationships among these patches remain elusive. In two monkeys, muscimol was infused sequentially into each patch or pair of patches to assess their respective influence on the remaining IT face network and the amygdala, as determined using fMRI. The results revealed that anterior face patches required input from middle face patches for their responses to both faces and objects, while the face selectivity in middle face patches arose, in part, from top-down input from anterior face patches. Moreover, we uncovered a parallel fundal-lateral functional organization in the IT face network, supporting dual routes (dorsal-ventral) in face processing within IT cortex as well as between IT cortex and the amygdala. Our findings of the causal relationship among the face patches demonstrate that the IT face circuit is organized into multiple functional compartments.


Assuntos
Mapeamento Encefálico , Imageamento por Ressonância Magnética , Animais , Estimulação Luminosa/métodos , Macaca mulatta , Córtex Cerebral/fisiologia , Reconhecimento Visual de Modelos/fisiologia
4.
Sci Rep ; 12(1): 20353, 2022 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-36437311

RESUMO

The other-race effect refers to the phenomenon in which the chance of individuals misidentifying faces from other races more than their own race is significantly higher. This study explored the effect of motivation on the other-race effect by manipulating the social status of faces. The results showed that: (1) compared to other-race faces with low social status, when individuals' perceptions of the social status of other-race faces increased, individuals' recognition scores for high social status other-race faces increased, and the other-race effect disappeared, and (2) when individuals' perceptions of the social status of other-race faces decreased, there was no significant difference in individuals' recognition scores of other-race faces, of either high or low social status. These findings suggest that motivation has a significant impact on the other-race effect.


Assuntos
Motivação , Reconhecimento Visual de Modelos , Humanos , Face , Status Social , Grupos Raciais
5.
Curr Biol ; 32(21): R1224-R1225, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36347228

RESUMO

The discovery of mental rotation was one of the most significant landmarks in experimental psychology, leading to the ongoing assumption that to visually compare objects from different three-dimensional viewpoints, we use explicit internal simulations of object rotations, to 'mentally adjust' one object until it matches the other1. These rotations are thought to be performed on three-dimensional representations of the object, by literal analogy to physical rotations. In particular, it is thought that an imagined object is continuously adjusted at a constant three-dimensional angular rotation rate from its initial orientation to the final orientation through all intervening viewpoints2. While qualitative theories have tried to account for this phenomenon3, to date there has been no explicit, image-computable model of the underlying processes. As a result, there is no quantitative account of why some object viewpoints appear more similar to one another than others when the three-dimensional angular difference between them is the same4,5. We reasoned that the specific pattern of non-uniformities in the perception of viewpoints can reveal the visual computations underlying mental rotation. We therefore compared human viewpoint perception with a model based on the kind of two-dimensional 'optical flow' computations that are thought to underlie motion perception in biological vision6, finding that the model reproduces the specific errors that participants make. This suggests that mental rotation involves simulating the two-dimensional retinal image change that would occur when rotating objects. When we compare objects, we do not do so in a distal three-dimensional representation as previously assumed, but by measuring how much the proximal stimulus would change if we watched the object rotate, capturing perspectival appearance changes7.


Assuntos
Percepção de Movimento , Fluxo Óptico , Humanos , Reconhecimento Visual de Modelos , Percepção Visual
6.
Sci Rep ; 12(1): 20068, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36418411

RESUMO

The arrangement of objects in scenes follows certain rules ("Scene Grammar"), which we exploit to perceive and interact efficiently with our environment. We have proposed that Scene Grammar is hierarchically organized: scenes are divided into clusters of objects ("phrases", e.g., the sink phrase); within every phrase, one object ("anchor", e.g., the sink) holds strong predictions about identity and position of other objects ("local objects", e.g., a toothbrush). To investigate if this hierarchy is reflected in the mental representations of objects, we collected pairwise similarity judgments for everyday object pictures and for the corresponding words. Similarity judgments were stronger not only for object pairs appearing in the same scene, but also object pairs appearing within the same phrase of the same scene as opposed to appearing in different phrases of the same scene. Besides, object pairs with the same status in the scenes (i.e., being both anchors or both local objects) were judged as more similar than pairs of different status. Comparing effects between pictures and words, we found similar, significant impact of scene hierarchy on the organization of mental representation of objects, independent of stimulus modality. We conclude that the hierarchical structure of visual environment is incorporated into abstract, domain general mental representations of the world.


Assuntos
Julgamento , Reconhecimento Visual de Modelos
7.
Sci Rep ; 12(1): 18896, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36344573

RESUMO

People more accurately remember faces of their own racial group compared to faces of other racial groups; this phenomenon is called the other-race effect. To date, numerous researchers have devoted themselves to exploring the reasons for this other-race effect, and they have posited several theoretical explanations. One integrated explanation is the categorization-individuation model, which addresses two primary ways (categorization and individuation) of racial face processing and emphasizes the emergence of these two ways during the encoding stage. Learning-recognition and racial categorization tasks are two classical tasks used to explore racial face processing. Event-related potentials can facilitate investigation of the encoding differences of own- and other-race faces under these two typical task demands. Unfortunately, to date, results have been mixed. In the current study, we investigated whether categorization and individuation differ for own- and other-race faces during the encoding stage by using racial categorization and learning-recognition tasks. We found that task demands not only influence the encoding of racial faces, but also have a more profound effect in the encoding stage of recognition tasks for other-race faces. More specifically, own-race faces demonstrate deeper structural encoding than other-race faces, with less attentional involvement. Moreover, recognitions tasks might ask for more individual-level encoding, requiring more attentional resources in the early stage that may be maintained until relatively late stages. Our results provide some evidence concerning task selection for future racial face studies and establish a groundwork for a unified interpretation of racial face encoding.


Assuntos
Reconhecimento Facial , Brancos , Humanos , Reconhecimento Psicológico , Potenciais Evocados , Grupos Raciais , Reconhecimento Visual de Modelos
8.
Commun Biol ; 5(1): 1247, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36376446

RESUMO

Distinguishing animate from inanimate things is of great behavioural importance. Despite distinct brain and behavioural responses to animate and inanimate things, it remains unclear which object properties drive these responses. Here, we investigate the importance of five object dimensions related to animacy ("being alive", "looking like an animal", "having agency", "having mobility", and "being unpredictable") in brain (fMRI, EEG) and behaviour (property and similarity judgements) of 19 participants. We used a stimulus set of 128 images, optimized by a genetic algorithm to disentangle these five dimensions. The five dimensions explained much variance in the similarity judgments. Each dimension explained significant variance in the brain representations (except, surprisingly, "being alive"), however, to a lesser extent than in behaviour. Different brain regions sensitive to animacy may represent distinct dimensions, either as accessible perceptual stepping stones toward detecting whether something is alive or because they are of behavioural importance in their own right.


Assuntos
Encéfalo , Reconhecimento Visual de Modelos , Humanos , Reconhecimento Visual de Modelos/fisiologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Mapeamento Encefálico , Imageamento por Ressonância Magnética/métodos , Julgamento/fisiologia
9.
Sci Rep ; 12(1): 19231, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36357416

RESUMO

Visual search is to find targets while ignoring distractors. Previous studies established that a target is more difficult to identify if aligned collinearly with other items, called the collinear search impairment. Since older adults have lower perceptual grouping ability than younger adults, benefits in visual search may occur for older adults for they may be less distracted by the collinear distractors. Three experiments were carried out to compare 45 younger and 45 older healthy adults. Participants were asked to identify a local target either in the column with items collinearly aligned to each other (the overlapping condition) or in the background (the non-overlapping condition), and the response difference between the two conditions is the collinear search impairment. Results showed that both groups showed reliable search impairment specific to collinear distractor regardless of grouping difficulty and task demands, and the impairment strength increased with the grouping strength of the collinear distractor. Further analysis revealed that the response times of older adults increased in a multiplicative manner to that of younger adults, suggesting that longer response of older adults spread to multiple underlying processing including grouping and suppression of collinear distractors. Together, the results suggest that older adults were still distracted in visual search even when grouping was required on a distractor. Our findings also highlight how general slowing may delay suppression processing in visual search.


Assuntos
Atenção , Reconhecimento Visual de Modelos , Humanos , Idoso , Reconhecimento Visual de Modelos/fisiologia , Atenção/fisiologia , Tempo de Reação , Percepção Visual/fisiologia
11.
Sci Rep ; 12(1): 18081, 2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36302932

RESUMO

We can easily perceive the spatial scale depicted in a picture, regardless of whether it is a small space (e.g., a close-up view of a chair) or a much larger space (e.g., an entire class room). How does the human visual system encode this continuous dimension? Here, we investigated the underlying neural coding of depicted spatial scale, by examining the voxel tuning and topographic organization of brain responses. We created naturalistic yet carefully-controlled stimuli by constructing virtual indoor environments, and rendered a series of snapshots to smoothly sample between a close-up view of the central object and far-scale view of the full environment (object-to-scene continuum). Human brain responses were measured to each position using functional magnetic resonance imaging. We did not find evidence for a smooth topographic mapping for the object-to-scene continuum on the cortex. Instead, we observed large swaths of cortex with opposing ramp-shaped profiles, with highest responses to one end of the object-to-scene continuum or the other, and a small region showing a weak tuning to intermediate scale views. However, when we considered the population code of the entire ventral occipito-temporal cortex, we found smooth and linear representation of the object-to-scene continuum. Our results together suggest that depicted spatial scale information is encoded parametrically in large-scale population codes across the entire ventral occipito-temporal cortex.


Assuntos
Córtex Visual , Humanos , Córtex Visual/fisiologia , Mapeamento Encefálico , Imageamento por Ressonância Magnética/métodos , Córtex Cerebral/fisiologia , Lobo Temporal , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa/métodos
12.
Trends Cogn Sci ; 26(12): 1119-1132, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36272937

RESUMO

A rich behavioral literature has shown that human object recognition is supported by a representation of shape that is tolerant to variations in an object's appearance. Such 'global' shape representations are achieved by describing objects via the spatial arrangement of their local features, or structure, rather than by the appearance of the features themselves. However, accumulating evidence suggests that the ventral visual pathway - the primary substrate underlying object recognition - may not represent global shape. Instead, ventral representations may be better described as a basis set of local image features. We suggest that this evidence forces a reevaluation of the role of the ventral pathway in object perception and posits a broader network for shape perception that encompasses contributions from the dorsal pathway.


Assuntos
Reconhecimento Visual de Modelos , Vias Visuais , Humanos , Percepção Visual , Encéfalo , Imageamento por Ressonância Magnética
13.
J Vis ; 22(11): 14, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36301525

RESUMO

The appearance of a face can be strongly affected by adaptation to faces seen previously. A number of studies have examined the time course of these aftereffects, but the integration time over which adaptation pools signals to control the adaptation state remains uncertain. Here we examined the effects of temporal frequency on face gender aftereffects induced by a pair of faces alternating between the two genders to assess when the aftereffects were pooled over successive faces versus driven by the last face seen. In the first experiment, we found that temporal frequencies between 0.25 and 2.00 Hz all failed to produce an aftereffect, suggesting a fairly long integration time. In the second experiment, we therefore probed slower alternation rates of 0.03 to 0.25 Hz. A rate of 0.0625 Hz (i.e., 8 seconds per face) was required to generate significant aftereffects from the last presented face and was consistent with an average time constant of 15 to 20 seconds for an exponentially decaying integration window. This integration time is substantially longer than found previously for analogous effects for alternating colors, and thus points to a potentially slower mechanism of adaptation for faces compared with chromatic adaptation.


Assuntos
Pós-Efeito de Figura , Humanos , Feminino , Masculino , Face , Adaptação Fisiológica , Estimulação Luminosa , Reconhecimento Visual de Modelos
14.
Psychol Sci ; 33(10): 1635-1650, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36219574

RESUMO

Face masks, which became prevalent across the globe during the COVID-19 pandemic, have had a negative impact on face recognition despite the availability of critical information from uncovered face parts, especially the eyes. An outstanding question is whether face-mask effects would be attenuated following extended natural exposure. This question also pertains, more generally, to face-recognition training protocols. We used the Cambridge Face Memory Test in a cross-sectional study (N = 1,732 adults) at six different time points over a 20-month period, alongside a 12-month longitudinal study (N = 208). The results of the experiments revealed persistent deficits in recognition of masked faces and no sign of improvement across time points. Additional experiments verified that the amount of individual experience with masked faces was not correlated with the mask effect. These findings provide compelling evidence that the face-processing system does not easily adapt to visual changes in face stimuli, even following prolonged real-life exposure.


Assuntos
COVID-19 , Reconhecimento Facial , Adulto , COVID-19/epidemiologia , Estudos Transversais , Humanos , Estudos Longitudinais , Pandemias , Reconhecimento Visual de Modelos
15.
Cogn Neuropsychol ; 39(3-4): 155-169, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36202620

RESUMO

Response times (RTs) are commonly used to assess cognitive abilities, though it is unclear whether face processing RTs predict recognition ability beyond accuracy. In the current study, we examined accuracy and RT on a widely used face matching assessment modified to collect meaningful RT data, the computerized Benton Facial Recognition Test (BFRT-c), and measured whether RTs predicted face recognition ability and developmental prosopagnosia (DP) vs. control group membership. 62 controls and 36 DPs performed the BFRT-c as well as validated measures of face recognition ability: the Cambridge Face Memory Test (CFMT) and a Famous Faces Memory Test (FFMT). In controls, BFRT-c accuracy robustly predicted CFMT (r = .49, p < .001), FFMT (r = .43, p < .001), and a CFMT-FFMT composite (r = .54, p < .001), whereas BFRT-c RT was not significantly associated with these measures (all r's .21). We also found that BFRT-c accuracy significantly differed between DPs and controls, but RT failed to differentiate the groups.


Assuntos
Reconhecimento Facial , Prosopagnosia , Humanos , Reconhecimento Visual de Modelos , Prosopagnosia/psicologia , Tempo de Reação , Reconhecimento Psicológico/fisiologia
17.
Curr Biol ; 32(19): R1012-R1015, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36220088

RESUMO

In visual cortex, anatomically distinct patches respond to distinct categories, such as faces or text. New research confirms this parcellation using unsupervised analysis of functional magnetic resonance imaging data obtained from humans viewing tens of thousands of images, discovering one more preference: for food.


Assuntos
Mapeamento Encefálico , Córtex Visual , Análise de Dados , Humanos , Imageamento por Ressonância Magnética , Reconhecimento Visual de Modelos
18.
JAMA Health Forum ; 3(1): e214958, 2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36218858
19.
J Opt Soc Am A Opt Image Sci Vis ; 39(6): B50-B64, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36215527

RESUMO

Contrast discrimination determines the threshold contrast required to distinguish between two suprathreshold visual stimuli. It is typically measured using sine-wave gratings. We first present a modification to Barten's semi-mechanistic contrast discrimination model to account for spatial frequency effects and demonstrate how the model can successfully predict visual thresholds obtained from published classical contrast discrimination studies. Contrast discrimination functions are then measured from images of natural scenes, using a psychophysical paradigm based on that employed in our previous study of contrast detection sensitivity. The proposed discrimination model modification is shown to successfully predict discrimination thresholds for structurally very different types of natural image stimuli. A comparison of results shows that, for normal contrast levels in natural scene viewing, contextual contrast detection and discrimination are approximately the same and almost independent of spatial frequency within the range of 1-20 c/deg. At higher frequencies, both sensitivities decrease in magnitude due to optical limitations of the eye. The results are discussed in relation to current image quality models.


Assuntos
Sensibilidades de Contraste , Reconhecimento Visual de Modelos , Limiar Sensorial , Percepção Visual
20.
Sensors (Basel) ; 22(20)2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36298105

RESUMO

The diffractive deep neural network (D2NN) can efficiently accomplish 2D object recognition based on rapid optical manipulation. Moreover, the multiple-view D2NN array (MDA) possesses the obvious advantage of being able to effectively achieve 3D object classification. At present, 3D target recognition should be performed in a high-speed and dynamic way. It should be invariant to the typical shifting, scaling, and rotating variance of targets in relatively complicated circumstances, which remains a shortcoming of optical neural network architectures. In order to efficiently recognize 3D targets based on the developed D2NN, a more robust MDA (mr-MDA) is proposed in this paper. Through utilizing a new training strategy to tackle several random disturbances introduced into the optical neural network system, a trained mr-MDA model constructed by us was numerically verified, demonstrating that the training strategy is able to dynamically recognize 3D objects in a relatively stable way.


Assuntos
Redes Neurais de Computação , Reconhecimento Visual de Modelos , Percepção Visual , Reconhecimento Psicológico
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