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1.
Nat Commun ; 12(1): 4745, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34362883

RESUMO

Spatial processing by receptive fields is a core property of the visual system. However, it is unknown how spatial processing in high-level regions contributes to recognition behavior. As face inversion is thought to disrupt typical holistic processing of information in faces, we mapped population receptive fields (pRFs) with upright and inverted faces in the human visual system. Here we show that in face-selective regions, but not primary visual cortex, pRFs and overall visual field coverage are smaller and shifted downward in response to face inversion. From these measurements, we successfully predict the relative behavioral detriment of face inversion at different positions in the visual field. This correspondence between neural measurements and behavior demonstrates how spatial processing in face-selective regions may enable holistic perception. These results not only show that spatial processing in high-level visual regions is dynamically used towards recognition, but also suggest a powerful approach for bridging neural computations by receptive fields to behavior.


Assuntos
Face/fisiologia , Reconhecimento Facial/fisiologia , Orientação/fisiologia , Processamento Espacial/fisiologia , Adulto , Comportamento , Encéfalo , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Reconhecimento Visual de Modelos/fisiologia , Reconhecimento Psicológico/fisiologia , Córtex Visual/fisiologia , Campos Visuais/fisiologia , Adulto Jovem
2.
Nat Commun ; 12(1): 4597, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34321483

RESUMO

Sensory processing necessitates discarding some information in service of preserving and reformatting more behaviorally relevant information. Sensory neurons seem to achieve this by responding selectively to particular combinations of features in their inputs, while averaging over or ignoring irrelevant combinations. Here, we expose the perceptual implications of this tradeoff between selectivity and invariance, using stimuli and tasks that explicitly reveal their opposing effects on discrimination performance. We generate texture stimuli with statistics derived from natural photographs, and ask observers to perform two different tasks: Discrimination between images drawn from families with different statistics, and discrimination between image samples with identical statistics. For both tasks, the performance of an ideal observer improves with stimulus size. In contrast, humans become better at family discrimination but worse at sample discrimination. We demonstrate through simulations that these behaviors arise naturally in an observer model that relies on a common set of physiologically plausible local statistical measurements for both tasks.


Assuntos
Discriminação Psicológica/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Percepção Visual/fisiologia , Humanos , Estimulação Luminosa , Psicofísica
3.
Psychol Aging ; 36(4): 433-451, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34124920

RESUMO

Age-related differences in visual search have been extensively studied using simple item arrays, showing an attentional decline. Little is known about how aging affects attentional guidance during search in more complex scenes. To study this issue, we analyzed eye-movement behavior in realistic scene search. We examined age-related differences in top-down guidance, manipulating target template specificity (picture vs. word cue) and target-scene semantic consistency (consistent vs. inconsistent), and in bottom-up guidance, manipulating perceptual salience (high vs. low) of targets and distractors. Compared to young adults (YA), older adults (OA) were overall slower, from the first saccade in the scene. They showed a smaller benefit of a specific target template, suggesting that precision of visual information in working memory may decrease with age. The benefit of semantic consistency did not depend on age, suggesting a preserved ability in OA to use knowledge about object occurrence in scenes. OA showed greater bottom-up search facilitation due to target's high salience, which may depend on reduced selection of low-salience stimuli. Attentional capture by distractors was greater in OA than YA, with respect to engagement (probability of distractor fixation), but only following a picture cue, and disengagement (fixation duration on distractors) in all conditions. Overall, our study shows that age-related differences in visual selection of targets and distractors depend on specific task demands in terms of top-down and bottom-up guidance. It also indicates that scene search difficulties in OA can be limited by cognitive and perceptual forms of environmental support. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Assuntos
Reconhecimento Visual de Modelos/fisiologia , Adulto , Idoso , Envelhecimento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
4.
Cogn Res Princ Implic ; 6(1): 41, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34046743

RESUMO

The novel coronavirus disease 2019 (COVID-19) has considerably heightened health and financial concerns for many individuals. Similar concerns, such as those associated with poverty, impair performance on cognitive control tasks. If ongoing concerns about COVID-19 substantially increase the tendency to mind wander in tasks requiring sustained attention, these worries could degrade performance on a wide range of tasks, leading, for example, to increased traffic accidents, diminished educational achievement, and lower workplace productivity. In two pre-registered experiments, we investigated the degree to which young adults' concerns about COVID-19 correlated with their ability to sustain attention. Experiment 1 tested mainly European participants during an early phase of the pandemic. After completing a survey probing COVID-related concerns, participants engaged in a continuous performance task (CPT) over two, 4-min blocks, during which they responded to city scenes that occurred 90% of the time and withheld responses to mountain scenes that occurred 10% of the time. Despite large and stable individual differences, performance on the scene CPT did not significantly correlate with the severity of COVID-related concerns obtained from the survey. Experiment 2 tested US participants during a later phase of the pandemic. Once again, CPT performance did not significantly correlate with COVID concerns expressed in a pre-task survey. However, participants who had more task-unrelated thoughts performed more poorly on the CPT. These findings suggest that although COVID-19 increased anxiety in a broad swath of society, young adults are able to hold these concerns in a latent format, minimizing their impact on performance in a demanding sustained attention task.


Assuntos
Ansiedade/etiologia , Ansiedade/fisiopatologia , Atenção/fisiologia , COVID-19 , Reconhecimento Visual de Modelos/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Europa (Continente) , Feminino , Humanos , Masculino , Estados Unidos , Adulto Jovem
5.
Commun Biol ; 4(1): 487, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33879819

RESUMO

Stimulus identification commonly improves with repetition over long delays ("repetition priming"), whereas neural activity commonly decreases ("repetition suppression"). Multiple models have been proposed to explain this brain-behavior relationship, predicting alterations in functional and/or effective connectivity (Synchrony and Predictive Coding models), in the latency of neural responses (Facilitation model), and in the relative similarity of neural representations (Sharpening model). Here, we test these predictions with fMRI during overt and covert naming of repeated and novel objects. While we find partial support for predictions of the Facilitation and Sharpening models in the left fusiform gyrus and left frontal cortex, the data were most consistent with the Synchrony model, with increased coupling between right temporoparietal and anterior cingulate cortex for repeated objects that correlated with priming magnitude across participants. Increased coupling and repetition suppression varied independently, each explaining unique variance in priming and requiring modifications of all current models.


Assuntos
Imageamento por Ressonância Magnética , Priming de Repetição/fisiologia , Lobo Temporal/fisiologia , Adulto , Feminino , Humanos , Masculino , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa , Tempo de Reação , Adulto Jovem
6.
Nature ; 593(7859): 411-417, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33883745

RESUMO

The ability to categorize sensory stimuli is crucial for an animal's survival in a complex environment. Memorizing categories instead of individual exemplars enables greater behavioural flexibility and is computationally advantageous. Neurons that show category selectivity have been found in several areas of the mammalian neocortex1-4, but the prefrontal cortex seems to have a prominent role4,5 in this context. Specifically, in primates that are extensively trained on a categorization task, neurons in the prefrontal cortex rapidly and flexibly represent learned categories6,7. However, how these representations first emerge in naive animals remains unexplored, leaving it unclear whether flexible representations are gradually built up as part of semantic memory or assigned more or less instantly during task execution8,9. Here we investigate the formation of a neuronal category representation throughout the entire learning process by repeatedly imaging individual cells in the mouse medial prefrontal cortex. We show that mice readily learn rule-based categorization and generalize to novel stimuli. Over the course of learning, neurons in the prefrontal cortex display distinct dynamics in acquiring category selectivity and are differentially engaged during a later switch in rules. A subset of neurons selectively and uniquely respond to categories and reflect generalization behaviour. Thus, a category representation in the mouse prefrontal cortex is gradually acquired during learning rather than recruited ad hoc. This gradual process suggests that neurons in the medial prefrontal cortex are part of a specific semantic memory for visual categories.


Assuntos
Aprendizagem/fisiologia , Modelos Neurológicos , Reconhecimento Visual de Modelos/fisiologia , Córtex Pré-Frontal/fisiologia , Animais , Feminino , Memória/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/fisiologia , Estimulação Luminosa , Córtex Pré-Frontal/citologia , Fatores de Tempo
7.
Nat Commun ; 12(1): 2453, 2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33907186

RESUMO

Parasitoid wasps inflict widespread death upon the insect world. Hundreds of thousands of parasitoid wasp species kill a vast range of insect species. Insects have evolved defensive responses to the threat of wasps, some cellular and some behavioral. Here we find an unexpected response of adult Drosophila to the presence of certain parasitoid wasps: accelerated mating behavior. Flies exposed to certain wasp species begin mating more quickly. The effect is mediated via changes in the behavior of the female fly and depends on visual perception. The sight of wasps induces the dramatic upregulation in the fly nervous system of a gene that encodes a 41-amino acid micropeptide. Mutational analysis reveals that the gene is essential to the behavioral response of the fly. Our work provides a foundation for further exploration of how the activation of visual circuits by the sight of a wasp alters both sexual behavior and gene expression.


Assuntos
Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila simulans/genética , Drosophila/genética , Receptores Ionotrópicos de Glutamato/genética , Receptores Odorantes/genética , Comportamento Sexual Animal/fisiologia , Vespas/patogenicidade , Adaptação Fisiológica , Animais , Animais Geneticamente Modificados , Carnivoridade/fisiologia , Drosophila/metabolismo , Drosophila/parasitologia , Proteínas de Drosophila/deficiência , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Drosophila melanogaster/parasitologia , Drosophila simulans/metabolismo , Drosophila simulans/parasitologia , Feminino , Fertilidade/genética , Regulação da Expressão Gênica , Masculino , Neurônios/citologia , Neurônios/metabolismo , Reconhecimento Visual de Modelos/fisiologia , Receptores Ionotrópicos de Glutamato/deficiência , Receptores Odorantes/deficiência , Vespas/fisiologia , beta-Caroteno 15,15'-Mono-Oxigenase/genética , beta-Caroteno 15,15'-Mono-Oxigenase/metabolismo
8.
Nat Commun ; 12(1): 1872, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33767141

RESUMO

Deep neural networks have revolutionized computer vision, and their object representations across layers match coarsely with visual cortical areas in the brain. However, whether these representations exhibit qualitative patterns seen in human perception or brain representations remains unresolved. Here, we recast well-known perceptual and neural phenomena in terms of distance comparisons, and ask whether they are present in feedforward deep neural networks trained for object recognition. Some phenomena were present in randomly initialized networks, such as the global advantage effect, sparseness, and relative size. Many others were present after object recognition training, such as the Thatcher effect, mirror confusion, Weber's law, relative size, multiple object normalization and correlated sparseness. Yet other phenomena were absent in trained networks, such as 3D shape processing, surface invariance, occlusion, natural parts and the global advantage. These findings indicate sufficient conditions for the emergence of these phenomena in brains and deep networks, and offer clues to the properties that could be incorporated to improve deep networks.


Assuntos
Modelos Neurológicos , Redes Neurais de Computação , Reconhecimento Visual de Modelos/fisiologia , Córtex Visual/fisiologia , Humanos , Percepção Visual/fisiologia
9.
J Vis ; 21(3): 14, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33688921

RESUMO

Shape perception varies depending on many factors. For example, presenting a stimulus in the periphery often yields a different appearance compared with its foveal presentation. However, how exactly shape appearance is altered under different conditions remains elusive. One reason for this is that studies typically measure identification performance, leaving details about target appearance unknown. The lack of appearance-based methods and general challenges to quantify appearance complicate the investigation of shape appearance. Here, we introduce Geometrically Restricted Image Descriptors (GRIDs), a method to investigate the appearance of shapes. Stimuli in the GRID paradigm are shapes consisting of distinct line elements placed on a grid by connecting grid nodes. Each line is treated as a discrete target. Observers are asked to capture target appearance by placing lines on a freely viewed response grid. We used GRIDs to investigate the appearance of letters and letter-like shapes. Targets were presented at 10° eccentricity in the right visual field. Gaze-contingent stimulus presentation was used to prevent eye movements to the target. The data were analyzed by quantifying the differences between targets and response in regard to overall accuracy, element discriminability, and several distinct error types. Our results show how shape appearance can be captured by GRIDs, and how a fine-grained analysis of stimulus parts provides quantifications of appearance typically not available in standard measures of performance. We propose that GRIDs are an effective tool to investigate the appearance of shapes.


Assuntos
Percepção de Forma/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Biologia Computacional , Discriminação Psicológica , Movimentos Oculares/fisiologia , Feminino , Humanos , Masculino , Mascaramento Perceptivo , Campos Visuais/fisiologia , Adulto Jovem
10.
J Vis ; 21(3): 15, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33704373

RESUMO

Divided attention has little effect for simple tasks, such as luminance detection, but it has large effects for complex tasks, such as semantic categorization of masked words. Here, we asked whether the semantic categorization of visual objects shows divided attention effects as large as those observed for words, or as small as those observed for simple feature judgments. Using a dual-task paradigm with nameable object stimuli, performance was compared with the predictions of serial and parallel models. At the extreme, parallel processes with unlimited capacity predict no effect of divided attention; alternatively, an all-or-none serial process makes two predictions: a large divided attention effect (lower accuracy for dual-task trials, compared to single-task trials) and a negative response correlation in dual-task trials (a given response is more likely to be incorrect when the response about the other stimulus is correct). These predictions were tested in two experiments examining object judgments. In both experiments, there was a large divided attention effect and a small negative correlation in responses. The magnitude of these effects was larger than for simple features, but smaller than for words. These effects were consistent with serial models, and rule out some but not all parallel models. More broadly, the results help establish one of the first examples of likely serial processing in perception.


Assuntos
Reconhecimento Visual de Modelos/fisiologia , Mascaramento Perceptivo/fisiologia , Percepção Visual/fisiologia , Adulto , Atenção/fisiologia , Feminino , Humanos , Julgamento , Masculino , Tempo de Reação/fisiologia
11.
J Vis ; 21(3): 16, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33724362

RESUMO

With the rise of machines to human-level performance in complex recognition tasks, a growing amount of work is directed toward comparing information processing in humans and machines. These studies are an exciting chance to learn about one system by studying the other. Here, we propose ideas on how to design, conduct, and interpret experiments such that they adequately support the investigation of mechanisms when comparing human and machine perception. We demonstrate and apply these ideas through three case studies. The first case study shows how human bias can affect the interpretation of results and that several analytic tools can help to overcome this human reference point. In the second case study, we highlight the difference between necessary and sufficient mechanisms in visual reasoning tasks. Thereby, we show that contrary to previous suggestions, feedback mechanisms might not be necessary for the tasks in question. The third case study highlights the importance of aligning experimental conditions. We find that a previously observed difference in object recognition does not hold when adapting the experiment to make conditions more equitable between humans and machines. In presenting a checklist for comparative studies of visual reasoning in humans and machines, we hope to highlight how to overcome potential pitfalls in design and inference.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Reconhecimento Visual de Modelos/fisiologia , Percepção Visual/fisiologia , Inteligência Artificial , Humanos , Aprendizagem/fisiologia , Resolução de Problemas , Reconhecimento Psicológico
12.
J Vis ; 21(3): 22, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33769442

RESUMO

People commonly track objects moving in complex natural displays and their performance in the multiple object tracking paradigm has been used to study such visual attention for more than three decades. Given the theoretical and practical importance of object tracking, it is critical to understand how people solve the correspondence problem to track objects; however, it remains unclear what information people use to achieve this feat. In particular, although people can track multiple moving objects based on their positions, there is ambiguity about whether people can track objects via higher order kinematic information, such as velocity. We designed a paradigm in which position was rendered uninformative to directly examine whether people could use higher order kinematic information to track multiple objects. We find that people can track via velocity, but not acceleration, even though observers can reliably detect the acceleration cue that they cannot use for tracking. Furthermore, we show a capacity constraint on using higher order kinematic information-people perform worse when required to use velocity to resolve correspondence for multiple object pairs simultaneously. Together, our results suggest that, although people can use higher order kinematic information for object tracking, precise higher order kinematic information is not freely available from the early visual system.


Assuntos
Fenômenos Biomecânicos , Percepção de Movimento/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Aceleração , Humanos , Análise e Desempenho de Tarefas
13.
PLoS One ; 16(2): e0247310, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33606816

RESUMO

In social animals, recognizing conspecifics and distinguishing them from other animal species is certainly important. We hypothesize, as demonstrated in other species of ungulates, that horses are able to discriminate between the faces of conspecifics and the faces of other domestic species (cattle, sheep, donkeys and pigs). Our hypothesis was tested by studying inter-and intra-specific visual discrimination abilities in horses through a two-way instrumental conditioning task (discrimination and reversal learning), using two-dimensional images of faces as discriminative stimuli and food as a positive reward. Our results indicate that 8 out of 10 horses were able to distinguish between two-dimensional images of the faces of horses and images showing the faces of other species. A similar performance was obtained in the reversal task. The horses' ability to learn by discrimination is therefore comparable to other ungulates. Horses also showed the ability to learn a reversal task. However, these results were obtained regardless of the images the tested horses were exposed to. We therefore conclude that horses can discriminate between two dimensional images of conspecifics and two dimensional images of different species, however in our study, they were not able to make further subcategories within each of the two categories. Despite the fact that two dimensional images of animals could be treated differently from two dimensional images of non-social stimuli, our results beg the question as to whether a two-dimensional image can replace the real animal in cognitive tests.


Assuntos
Aprendizagem por Discriminação/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Percepção Visual/fisiologia , Animais , Animais Domésticos , Bovinos , Discriminação Psicológica , Feminino , Cavalos , Masculino , Reconhecimento Psicológico
14.
Psychon Bull Rev ; 28(3): 969-977, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33565044

RESUMO

Companies and products are identified by their brand names, which are typically written with a specific letter style, color, and design (i.e., logos). This graphical information offers a distinctive image that facilitates their recognition. However, the uniqueness of these configuration cues may make brand names more vulnerable to counterfeiting via misspelling. We examined whether the confusability at detecting misspelled brand names is higher when embedded in the full logo than when presented in plain format (Experiment 1), when removing all graphical information of the logo other than typeface (Experiment 2), and when only modifying the typeface (Experiment 3). Participants had to decide whether the presented item was a correctly spelled brand name. The misspelled stimuli were created by either transposing or replacing two internal letters of popular brand names (amazon → amzaon vs. amceon), thus allowing us to have a measure of the transposed-letter confusability effect. Results showed a sizeable transposed-letter confusability effect for all types of brand names, but the effect was greatest for the misspelled full logos. Thus, the distinctiveness of the graphical information in logos has a deleterious side effect: logos are quite vulnerable to counterfeiting via misspelling branding.


Assuntos
Comportamento do Consumidor , Reconhecimento Visual de Modelos/fisiologia , Reconhecimento Psicológico/fisiologia , Adulto , Sinais (Psicologia) , Feminino , Humanos , Masculino , Leitura , Adulto Jovem
15.
Proc Natl Acad Sci U S A ; 118(6)2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33526693

RESUMO

Grapheme-color synesthetes experience color when seeing achromatic symbols. We examined whether similar neural mechanisms underlie color perception and synesthetic colors using magnetoencephalography. Classification models trained on neural activity from viewing colored stimuli could distinguish synesthetic color evoked by achromatic symbols after a delay of ∼100 ms. Our results provide an objective neural signature for synesthetic experience and temporal evidence consistent with higher-level processing in synesthesia.


Assuntos
Percepção de Cores/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Sinestesia/fisiopatologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Magnetoencefalografia , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa , Tempo de Reação/fisiologia , Sinestesia/diagnóstico por imagem , Adulto Jovem
16.
J Vis ; 21(2): 1, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33533878

RESUMO

The deleterious effect of nearby flankers on target identification in the periphery is known as visual crowding. Studying visual crowding can advance our understanding of the mechanisms of visual awareness and object recognition. Alleviating visual crowding is one of the major ways to improve peripheral vision. The aim of the current study was to examine whether transcranial direct current stimulation (tDCS) was capable of alleviating visual crowding at different visual eccentricities and with different visual tasks. In the present single-blind sham-controlled study, subjects were instructed to perform an orientation discrimination task or a letter identification task with isolated and crowded targets in the periphery, before and after applying 20 minutes of 2 mA anodal tDCS to visual cortex of the hemisphere contralateral or ipsilateral to visual stimuli. Contralateral tDCS significantly alleviated the orientation crowding effect at two different eccentricities and the letter crowding effect. This alleviation was absent after sham or ipsilateral stimulation and could not be fully explained by the performance improvement with the isolated targets. These findings demonstrated that offline tDCS was effective in alleviating visual crowding across different visual eccentricities and tasks, therefore providing a promising way to improve spatial vision rapidly in crowded scenes.


Assuntos
Aglomeração , Reconhecimento Visual de Modelos/fisiologia , Mascaramento Perceptivo/fisiologia , Estimulação Transcraniana por Corrente Contínua/métodos , Córtex Visual/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Orientação , Método Simples-Cego , Adulto Jovem
17.
J Vis ; 21(2): 2, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33533879

RESUMO

Observing and recognizing materials is a fundamental part of our daily life. Under typical viewing conditions, we are capable of effortlessly identifying the objects that surround us and recognizing the materials they are made of. Nevertheless, understanding the underlying perceptual processes that take place to accurately discern the visual properties of an object is a long-standing problem. In this work, we perform a comprehensive and systematic analysis of how the interplay of geometry, illumination, and their spatial frequencies affects human performance on material recognition tasks. We carry out large-scale behavioral experiments where participants are asked to recognize different reference materials among a pool of candidate samples. In the different experiments, we carefully sample the information in the frequency domain of the stimuli. From our analysis, we find significant first-order interactions between the geometry and the illumination, of both the reference and the candidates. In addition, we observe that simple image statistics and higher-order image histograms do not correlate with human performance. Therefore, we perform a high-level comparison of highly nonlinear statistics by training a deep neural network on material recognition tasks. Our results show that such models can accurately classify materials, which suggests that they are capable of defining a meaningful representation of material appearance from labeled proximal image data. Last, we find preliminary evidence that these highly nonlinear models and humans may use similar high-level factors for material recognition tasks.


Assuntos
Percepção de Forma/fisiologia , Imageamento Tridimensional , Iluminação , Reconhecimento Visual de Modelos/fisiologia , Adulto , Feminino , Humanos , Masculino , Redes Neurais de Computação , Adulto Jovem
18.
J Vis ; 21(2): 5, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33560290

RESUMO

Defining target textures by increased bandwidths in spatial frequency and orientation, we observed strong cue combination effects in a combined texture figure detection and discrimination task. Performance for double-cue targets was better than predicted by independent processing of either cue and even better than predicted from linear cue integration. Application of a texture-processing model revealed that the oversummative cue combination effect is captured by calculating a low-level summary statistic (\(\Delta CE_m\)), which describes the differential contrast energy to target and reference textures, from multiple scales and orientations, and integrating this statistic across channels with a winner-take-all rule. Modeling detection performance using a signal detection theory framework showed that the observers' sensitivity to single-cue and double-cue texture targets, measured in \(d^{\prime }\) units, could be reproduced with plausible settings for filter and noise parameters. These results challenge models assuming separate channeling of elementary features and their later integration, since oversummative cue combination effects appear as an inherent property of local energy mechanisms, at least for spatial frequency and orientation bandwidth-modulated textures.


Assuntos
Orientação Espacial/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Adulto , Sensibilidades de Contraste , Feminino , Humanos , Masculino , Modelos Psicológicos , Adulto Jovem
19.
J Vis ; 21(2): 8, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33595646

RESUMO

Categorization performance is a popular metric of scene recognition and understanding in behavioral and computational research. However, categorical constructs and their labels can be somewhat arbitrary. Derived from exhaustive vocabularies of place names (e.g., Deng et al., 2009), or the judgements of small groups of researchers (e.g., Fei-Fei, Iyer, Koch, & Perona, 2007), these categories may not correspond with human-preferred taxonomies. Here, we propose clustering by increasing the rand index via coordinate ascent (CIRCA): an unsupervised, data-driven clustering method for deriving ground-truth scene categories. In Experiment 1, human participants organized 80 stereoscopic images of outdoor scenes from the Southampton-York Natural Scenes (SYNS) dataset (Adams et al., 2016) into discrete categories. In separate tasks, images were grouped according to i) semantic content, ii) three-dimensional spatial structure, or iii) two-dimensional image appearance. Participants provided text labels for each group. Using the CIRCA method, we determined the most representative category structure and then derived category labels for each task/dimension. In Experiment 2, we found that these categories generalized well to a larger set of SYNS images, and new observers. In Experiment 3, we tested the relationship between our category systems and the spatial envelope model (Oliva & Torralba, 2001). Finally, in Experiment 4, we validated CIRCA on a larger, independent dataset of same-different category judgements. The derived category systems outperformed the SUN taxonomy (Xiao, Hays, Ehinger, Oliva, & Torralba, 2010) and an alternative clustering method (Greene, 2019). In summary, we believe this novel categorization method can be applied to a wide range of datasets to derive optimal categorical groupings and labels from psychophysical judgements of stimulus similarity.


Assuntos
Reconhecimento Visual de Modelos/fisiologia , Reconhecimento Psicológico/fisiologia , Adolescente , Adulto , Atenção/fisiologia , Feminino , Humanos , Julgamento , Masculino , Psicofísica , Córtex Visual/fisiologia , Adulto Jovem
20.
J Vis ; 21(2): 9, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33620380

RESUMO

Visual translation tolerance refers to our capacity to recognize objects over a wide range of different retinal locations. Although translation is perhaps the simplest spatial transform that the visual system needs to cope with, the extent to which the human visual system can identify objects at previously unseen locations is unclear, with some studies reporting near complete invariance over 10 degrees and other reporting zero invariance at 4 degrees of visual angle. Similarly, there is confusion regarding the extent of translation tolerance in computational models of vision, as well as the degree of match between human and model performance. Here, we report a series of eye-tracking studies (total N = 70) demonstrating that novel objects trained at one retinal location can be recognized at high accuracy rates following translations up to 18 degrees. We also show that standard deep convolutional neural networks (DCNNs) support our findings when pretrained to classify another set of stimuli across a range of locations, or when a global average pooling (GAP) layer is added to produce larger receptive fields. Our findings provide a strong constraint for theories of human vision and help explain inconsistent findings previously reported with convolutional neural networks (CNNs).


Assuntos
Redes Neurais de Computação , Reconhecimento Automatizado de Padrão/métodos , Reconhecimento Visual de Modelos/fisiologia , Aprendizado Profundo , Feminino , Humanos , Masculino , Adulto Jovem
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