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1.
Behav Brain Funct ; 20(1): 8, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637870

RESUMO

One important role of the TPJ is the contribution to perception of the global gist in hierarchically organized stimuli where individual elements create a global visual percept. However, the link between clinical findings in simultanagnosia and neuroimaging in healthy subjects is missing for real-world global stimuli, like visual scenes. It is well-known that hierarchical, global stimuli activate TPJ regions and that simultanagnosia patients show deficits during the recognition of hierarchical stimuli and real-world visual scenes. However, the role of the TPJ in real-world scene processing is entirely unexplored. In the present study, we first localized TPJ regions significantly responding to the global gist of hierarchical stimuli and then investigated the responses to visual scenes, as well as single objects and faces as control stimuli. All three stimulus classes evoked significantly positive univariate responses in the previously localized TPJ regions. In a multivariate analysis, we were able to demonstrate that voxel patterns of the TPJ were classified significantly above chance level for all three stimulus classes. These results demonstrate a significant involvement of the TPJ in processing of complex visual stimuli that is not restricted to visual scenes and that the TPJ is sensitive to different classes of visual stimuli with a specific signature of neuronal activations.


Assuntos
Imageamento por Ressonância Magnética , Lobo Parietal , Humanos , Lobo Parietal/fisiologia , Reconhecimento Psicológico , Neuroimagem , Análise Multivariada , Estimulação Luminosa , Reconhecimento Visual de Modelos/fisiologia , Percepção Visual/fisiologia , Mapeamento Encefálico/métodos
2.
J Exp Child Psychol ; 242: 105890, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38460228

RESUMO

Attentional blink manifests in infants at 7 months of age, indicating that the working memory capacity of 7-month-olds is comparable to that of adults. However, attentional blink in infants under 7 months is not well understood. In this study, we conducted two experiments to investigate attentional blink in 5- and 6-month-old infants. The results of Experiment 1 demonstrated that attentional blinks were not observed with either a short lag (200 ms) or a long lag (800 ms). This suggests that 5- and 6-month-olds are unable to consolidate both targets regardless of the temporal distance between the two. We then split the infants into two groups by their age and conducted Experiment 2 with infants aged younger and older than 180 days to compare their consolidating ability to observe whether they could recognize a single item at 100-ms speed by presenting the same visual stream that was used in Experiment 1 except that one target was eliminated. The results showed that infants over 180 days of age could identify a single target in the visual stream at 100-ms presentation speed, whereas infants under 180 days could not. The findings of the current study indicate that the limitation of working memory capacity in infants under 7 months of age is a possible reason for the lack of attentional blink.


Assuntos
Intermitência na Atenção Visual , Adulto , Humanos , Lactente , Atenção , Reconhecimento Visual de Modelos , Memória de Curto Prazo
3.
Curr Biol ; 34(5): R195-R197, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38471446

RESUMO

The representation of visual shape is a critical component of our perception of the objects around us. A new study exploited shape aftereffects to reveal the high-dimensional space of geometric features our brains use to represent shape.


Assuntos
Percepção de Forma , Percepção Visual , Estimulação Luminosa/métodos , Visão Ocular , Reconhecimento Visual de Modelos
4.
Adv Neurobiol ; 36: 907-934, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38468069

RESUMO

People are continually exposed to the rich complexity generated by the repetition of fractal patterns at different size scales. Fractals are prevalent in natural scenery and also in patterns generated by artists and mathematicians. In this chapter, we will investigate the powerful significance of fractals for the human senses. In particular, we propose that fractals with mid-range complexity play a unique role in our visual experiences because the visual system has adapted to these prevalent natural patterns. This adaptation is evident at multiple stages of the visual system, ranging from data acquisition by the eye to processing of this data in the higher visual areas of the brain. Based on these results, we will discuss a fluency model in which the visual system processes mid-complexity fractals with relative ease. This fluency optimizes the observer's capabilities (such as enhanced attention and pattern recognition) and generates an aesthetic experience accompanied by a reduction in the observer's physiological stress levels. In addition to reviewing people's responses to viewing fractals, we will compare these responses to recent research focused on fractal sounds and fractal surface textures. We will extend our fractal fluency model to allow for stimuli across multiple senses.


Assuntos
Fractais , Tato , Humanos , Reconhecimento Visual de Modelos/fisiologia , Encéfalo , Atenção
5.
Sci Rep ; 14(1): 6628, 2024 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-38503810

RESUMO

This study examined the temporal profile of spatial frequency processing in a word reading task in 16 normal adult readers. They had to report the word presented in a 200 ms display using a four-alternative forced-choice task (4AFC). The stimuli were made of an additive combination of the signal (i.e. the target word) and of a visual white noise patch wherein the signal-to-noise ratio varied randomly across stimulus duration. Four spatial frequency conditions were defined for the signal component of the stimulus (bandpass Butterworth filters with center frequencies of 1.2, 2.4, 4.8 and 9.6 cycles per degree). In contrast to the coarse-to-fine theory of visual recognition, the results show that the highest spatial frequency range dominates early processing, with a shift toward lower spatial frequencies at later points during stimulus exposure. This pattern interacted in a complex way with the temporal frequency content of signal-to-noise oscillations. The outcome of individual data patterns classification by a machine learning algorithm according to the corresponding spatial frequency band further shows that the most salient spatial frequency signature is obtained when the time dimension within data patterns is recoded into its Fourier transform.


Assuntos
Reconhecimento Visual de Modelos , Análise de Fourier , Estimulação Luminosa
6.
Sci Rep ; 14(1): 6626, 2024 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-38503841

RESUMO

Developmental prosopagnosia (DP) is characterised by deficits in face identification. However, there is debate about whether these deficits are primarily perceptual, and whether they extend to other face processing tasks (e.g., identifying emotion, age, and gender; detecting faces in scenes). In this study, 30 participants with DP and 75 controls completed a battery of eight tasks assessing four domains of face perception (identity; emotion; age and gender; face detection). The DP group performed worse than the control group on both identity perception tasks, and one task from each other domain. Both identity perception tests uniquely predicted DP/control group membership, and performance on two measures of face memory. These findings suggest that deficits in DP may arise from issues with face perception. Some non-identity tasks also predicted DP/control group membership and face memory, even when face identity perception was accounted for. Gender perception and speed of face detection consistently predicted unique variance in group membership and face memory; several other tasks were only associated with some measures of face recognition ability. These findings indicate that face perception deficits in DP may extend beyond identity perception. However, the associations between tasks may also reflect subtle aspects of task demands or stimuli.


Assuntos
Reconhecimento Facial , Prosopagnosia , Humanos , Prosopagnosia/diagnóstico , Emoções , Reconhecimento Visual de Modelos
7.
Sci Rep ; 14(1): 6687, 2024 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509151

RESUMO

Congenital Prosopagnosia (CP) is an innate impairment in face perception with heterogeneous characteristics. It is still unclear if and to what degree holistic processing of faces is disrupted in CP. Such disruption would be expected to lead to a focus on local features of the face. In this study, we used binocular rivalry (BR) to implicitly measure face perception in conditions that favour holistic or local processing. The underlying assumption is that if stimulus saliency affects the perceptual dominance of a given stimulus in BR, one can deduce how salient a stimulus is for a given group (here: participants with and without CP) based on the measured perceptual dominance. A further open question is whether the deficit in face processing in CP extends to the processing of the facial display of emotions. In experiment 1, we compared predominance of upright and inverted faces displaying different emotions (fearful, happy, neutral) vs. houses between participants with CP (N = 21) and with normal face perception (N = 21). The results suggest that CP observers process emotions in faces automatically but rely more on local features than controls. The inversion of faces, which is supposed to disturb holistic processing, affected controls in a more pronounced way than participants with CP. In experiment 2, we introduced the Thatcher effect in BR by inverting the eye and mouth regions of the presented faces in the hope of further increasing the effect of face inversion. However, our expectations were not borne out by the results. Critically, both experiments showed that inversion effects were more pronounced in controls than in CP, suggesting that holistic face processing is less relevant in CP. We find BR to be a useful implicit test for assessing visual processing specificities in neurological participants.


Assuntos
Reconhecimento Facial , Prosopagnosia , Prosopagnosia/congênito , Humanos , Prosopagnosia/psicologia , Reconhecimento Visual de Modelos , Percepção Visual , Estimulação Luminosa
8.
Cognition ; 246: 105759, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38430752

RESUMO

A key issue in recent visual word recognition literature is whether text rotation disrupts the early stages of orthographic processing. Previous research found no masked repetition priming effect when primes were rotated ≥90° in alphabetic languages. The present study investigated the impact of text rotation using logographic (two-character Japanese kanji) words. In Experiment 1, we conducted a masked repetition priming lexical decision experiment with upright and 180° rotated primes. The rotated primes produced a significant priming effect, although the effect was smaller than the upright primes. In Experiment 2, we further examined the effectiveness of 180° rotated primes in two different conditions: the whole words were rotated vs. each constituent character was rotated at their own positions. Both prime types produced significant priming effects of similar magnitudes. These findings suggest that orthographic processing is more robust against text rotation in logographic languages than in alphabetic languages.


Assuntos
Reconhecimento Visual de Modelos , Leitura , Humanos , Rotação , Japão , Idioma , Priming de Repetição , Mascaramento Perceptivo
9.
Curr Biol ; 34(6): R235-R236, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38531313

RESUMO

An important task for the visual system is to identify and segregate objects from background. Figure-ground illusions, such as Edgar Rubin's bistable 'vase-faces illusion'1, make the point clearly: we see either a central vase or lateral faces, alternating spontaneously, but never both images simultaneously. The border is perceptually assigned to either faces or vase, which become figure, the other shapeless background2. The stochastic alternation between figure and ground probably reflects mutual inhibitory processes that ensure a single perceptual outcome3. Which shape dominates perception depends on many factors, such as size, symmetry, convexity, enclosure, and so on, as well as attention and intention4. Here we show that the assignment of the visual border can be strongly influenced by auditory input, far more than is possible by voluntary intention. VIDEO ABSTRACT.


Assuntos
Ilusões , Reconhecimento Visual de Modelos , Humanos , Estimulação Luminosa/métodos , Atenção , Face
10.
Cortex ; 173: 283-295, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38442567

RESUMO

Evidence suggests that some patients with isolated hippocampal damage appear to present with selective preservation of unfamiliar face recognition relative to other kinds of visual test stimuli (e.g., words). Bird and Burgess (2008) formulated a review and secondary analysis of a group of 10 cases all tested on a clinical assessment of word and face recognition memory (RMT, Warrington, 1984), which confirmed the key memory dissociation at the group level. The current work provides an updated secondary analysis of such cases with a larger published sample (N = 52). In addition to group-level analyses, we also re-evaluate evidence using a single case statistical approach (Crawford & Garthwaite, 2005), enabling us to determine how many would make criteria for a 'classical dissociation' (Crawford, Garthwaite, & Gray, 2003). Overall, group-level analyses indicated the key pattern of significant differences confined to words was limited to small control sample comparisons. When using the large control sample provided by Bird and Burgess (2008), hippocampal cases as a group were significantly poorer for both classes of items. Furthermore, our single-case approach indicated few had a performance pattern of a relative difference across face > word categories that would meet statistical significance; namely within individual differences across categories that would warrant a significant 'classical dissociation'. Moreover, these analyses also found several cases with a 'classical dissociation' in the reverse direction: namely preserved recognition of words. Such analyses serve to demonstrate the need for a more conservative statistical approach to be undertaken when reporting selective 'preservation' of a category in recognition memory. Whilst material specificity has important implications for understanding the role of the hippocampus in memory, our results highlight the need for statistical methods to be unquestionably rigorous before any claims are made. Lastly, we highlight other methodological issues critical to group analyses and make suggestions for future work.


Assuntos
Reconhecimento Facial , Humanos , Reconhecimento Psicológico , Amnésia , Hipocampo , Individualidade , Reconhecimento Visual de Modelos
11.
Cortex ; 173: 333-338, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38460488

RESUMO

Developmental prosopagnosia (DP) is characterised by difficulties recognising face identities and is associated with diverse co-occurring object recognition difficulties. The high co-occurrence rate and heterogeneity of associated difficulties in DP is an intrinsic feature of developmental conditions, where co-occurrence of difficulties is the rule, rather than the exception. However, despite its name, cognitive and neural theories of DP rarely consider the developmental context in which these difficulties occur. This leaves a large gap in our understanding of how DP emerges in light of the developmental trajectory of face recognition. Here, we argue that progress in the field requires re-considering the developmental origins of differences in face recognition abilities, rather than studying the end-state alone. In practice, considering development in DP necessitates a re-evaluation of current approaches in recruitment, design, and analyses.


Assuntos
Reconhecimento Facial , Prosopagnosia , Humanos , Percepção Visual , Reconhecimento Visual de Modelos
12.
J Vis ; 24(3): 1, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38427362

RESUMO

Previous work has found that feature attention can modulate electrophysiological responses to visual symmetry. In the current study, participants observed spatially overlapping clouds of black and white dots. They discriminated vertical symmetry from asymmetry in the target dots (e.g., black or white) and ignored the regularity of the distractor dots (e.g., white or black). We measured an electroencephalography component called the sustained posterior negativity (SPN), which is known to be generated by visual symmetry. There were five conditions with different combinations of target and distractor regularity. As well as replicating previous results, we found that an orthogonal axes of reflection in the distractor dots had no effect on SPN amplitude. We conclude that the visual system can processes reflectional symmetry in independent axis-orientation specific channels.


Assuntos
Eletroencefalografia , Reconhecimento Visual de Modelos , Humanos , Reconhecimento Visual de Modelos/fisiologia , Encéfalo/fisiologia , Atenção , Estimulação Luminosa
13.
J Exp Psychol Hum Percept Perform ; 50(5): 479-497, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38546626

RESUMO

How compound words are processed remains a central question in research on Chinese reading. The Chinese reading model assumes that all possible words sharing characters are activated during word processing and these activated words compete for a winner (Li & Pollatsek, 2020). The present studies aimed to examine whether embedded component words compete with whole compound words in Chinese reading. In Study 1, we analyzed two existing lexical decision databases and revealed inhibitory effects of component-word frequency and facilitative effects of character frequency on the first components. In Study 2, we conducted two factorial experiments to further examine the effects of first component-word frequency, with character frequencies controlled. The results consistently indicated significant inhibitory effects of component-word frequency. Collectively, these findings support the theoretical proposition that both component words and compound words are activated and engage in competition during word processing. This provides a new approach to compound word processing in Chinese reading and a possible solution to mixed results of character frequency effects reported in the literature. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Reconhecimento Visual de Modelos , Processamento de Texto , Humanos , China , Leitura
14.
Cortex ; 174: 70-92, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38492441

RESUMO

Reflectional (mirror) symmetry is an important visual cue for perceptual organization. The brain processes symmetry rapidly and efficiently. Previous work suggests that symmetry activates the extrastriate cortex and generates an event related potential (ERP) called the Sustained Posterior Negativity (SPN). It has been claimed that no tasks completely block symmetry processing and abolish the SPN. We tested the limits of this claim with a series of eight new Electroencephalography (EEG) experiments (344 participants in total). All experiments used the same symmetrical or asymmetrical dot patterns. When participants attended to regularity in Experiment 1, there was a substantial SPN (Mean amplitude = -2.423 µV). The SPN was reduced, but not abolished, when participants discriminated dot luminance in Experiments 2 and 3 (-.835 and -1.410 µV) or the aspect ratio of a superimposed cross in Experiments 4 and 5 (-.722 and -.601 µV). The SPN also survived when the background pattern was potentially disruptive to the primary task in Experiment 6 (-1.358 µV) and when participants classified negative superimposed words in Experiment 7 (-.510 µV). Finally, the SPN remained when participants attended to the orientation of a diagonal line in Experiment 8 (-.589 µV). While task manipulations can turn down the extrastriate symmetry activation, they cannot render the system completely unresponsive. Permanent readiness to detect reflectional symmetry at the centre of the visual field could be an evolved adaptation.


Assuntos
Potenciais Evocados , Reconhecimento Visual de Modelos , Humanos , Reconhecimento Visual de Modelos/fisiologia , Potenciais Evocados/fisiologia , Eletroencefalografia , Encéfalo/fisiologia , Campos Visuais
15.
J Exp Psychol Hum Percept Perform ; 50(5): 515-530, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38546627

RESUMO

Semantic context effects in picture naming and categorization tasks are central to the development and evaluation of current models of word production. When pictures are named in a semantically blocked context, response latencies are delayed. Belke (2013) found that when the naming task was replaced with a semantic categorization task (natural vs. man-made), response latencies were facilitated. From this pattern, she concluded that semantic interference in blocked picture naming has its locus at the lexical level but its origin at the preceding semantic level. However, other studies using the blocking procedure have failed to find facilitation in semantic categorization tasks (Damian et al., 2001; Riley et al., 2015), calling this conclusion into question. In three blocked picture naming and categorization experiments, we investigated different variables that might account for the discrepant results in semantic categorization. We used different semantic categorization tasks, different response modalities, different response set sizes, and different blocking procedures. Semantic facilitation was reliably found in naturalness categorization, but there was no semantic effect in natural size categorization. We discuss the implications of these findings for appropriate task selection. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Nomes , Semântica , Feminino , Humanos , Atenção/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Tempo de Reação/fisiologia
16.
Acta Psychol (Amst) ; 245: 104237, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38537601

RESUMO

Developmental prosopagnosia (DP) is a condition that indicates the inability to recognize individuals by their faces from birth, without any history of brain damage. The assessment of face recognition ability and diagnosis of DP involve the use of face tests such as the Cambridge Face Memory Test (CFMT) and the Cambridge Face Perception Test, along with self-reported measures like the 20-Item Prosopagnosia Index (PI20). Face recognition accuracy is affected by anxiety. However, previous studies on the relationship between face recognition ability and anxiety have not used the PI20 measure. This study aimed to investigate the relationship between self-reported measures of face recognition ability and anxiety tendencies among healthy young individuals for DP diagnosis and its implications. We used a face recognition test, involving the PI20, CFMT, Visual Perception Test for Agnosia-Famous Face Test (VPTA-FFT), and State-Trait Anxiety Inventory (STAI). We assessed the performance of 116 Japanese young adults (75 females, median age of 20.7 years, with a standard deviation of 1.2). Subsequently, we conducted a statistical analysis to examine the relationship between the outcomes of the face recognition tests and STAI scores using Pearson correlation analysis and single correlation coefficients. The results showed a positive correlation between state anxiety and PI20 (r = 0.308, p = 0.007), and a weak positive correlation was also observed between trait anxiety and PI20 (r = 0.268, p = 0.04). In contrast, there was no correlation between CFMT and VPTA-FFT with respect to STAI. The results of the hierarchical multiple regression analysis also suggested that the correlation between the performance on the PI20 (self-report) and objective measures of face recognition performance (the CFMT and the VPTA-FFT) are driven by differences in anxiety. This study is the first to explore the relationship between face recognition abilities and anxiety using the PI20 self-report measure. There are implications for future research on the diagnosis of DP and the relationship between anxiety and face recognition.


Assuntos
Reconhecimento Facial , Prosopagnosia , Feminino , Adulto Jovem , Humanos , Adulto , Prosopagnosia/diagnóstico , Reconhecimento Psicológico , Ansiedade/diagnóstico , Autorrelato , Reconhecimento Visual de Modelos
17.
J Exp Psychol Hum Percept Perform ; 50(4): 358-369, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38300565

RESUMO

Real-world object size is a behaviorally relevant object property that is automatically retrieved when viewing object images: participants are faster to indicate the bigger of two object images when this object is also bigger in the real world. What drives this size Stroop effect? One possibility is that it reflects the automatic retrieval of real-world size after objects are recognized at the basic level (e.g., recognizing an object as a plane activates large real-world size). An alternative possibility is that the size Stroop effect is driven by automatic associations between low-/mid-level visual features (e.g., rectilinearity) and real-world size, bypassing object recognition. Here, we tested both accounts. In Experiment 1, objects were displayed upright and inverted, slowing down recognition while equating visual features. Inversion strongly reduced the Stroop effect, indicating that object recognition contributed to the Stroop effect. Independently of inversion, however, trial-wise differences in rectilinearity also contributed to the Stroop effect. In Experiment 2, the Stroop effect was compared between manmade objects (for which rectilinearity was associated with size) and animals (no association between rectilinearity and size). The Stroop effect was larger for animals than for manmade objects, indicating that rectilinear feature differences were not necessary for the Stroop effect. Finally, in Experiment 3, unrecognizable "texform" objects that maintained size-related visual feature differences were displayed upright and inverted. Results revealed a small Stroop effect for both upright and inverted conditions. Altogether, these results indicate that the size Stroop effect partly follows object recognition with an additional contribution from visual feature associations. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Reconhecimento Psicológico , Percepção Visual , Humanos , Percepção Visual/fisiologia , Teste de Stroop , Reconhecimento Visual de Modelos/fisiologia
18.
J Neurosci ; 44(12)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38331583

RESUMO

Capacity limitations in visual tasks can be observed when the number of task-related objects increases. An influential idea is that such capacity limitations are determined by competition at the neural level: two objects that are encoded by shared neural populations interfere more in behavior (e.g., visual search) than two objects encoded by separate neural populations. However, the neural representational similarity of objects varies across brain regions and across time, raising the questions of where and when competition determines task performance. Furthermore, it is unclear whether the association between neural representational similarity and task performance is common or unique across tasks. Here, we used neural representational similarity derived from fMRI, MEG, and a deep neural network (DNN) to predict performance on two visual search tasks involving the same objects and requiring the same responses but differing in instructions: cued visual search and oddball visual search. Separate groups of human participants (both sexes) viewed the individual objects in neuroimaging experiments to establish the neural representational similarity between those objects. Results showed that performance on both search tasks could be predicted by neural representational similarity throughout the visual system (fMRI), from 80 ms after onset (MEG), and in all DNN layers. Stepwise regression analysis, however, revealed task-specific associations, with unique variability in oddball search performance predicted by early/posterior neural similarity and unique variability in cued search task performance predicted by late/anterior neural similarity. These results reveal that capacity limitations in superficially similar visual search tasks may reflect competition at different stages of visual processing.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Masculino , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Percepção Visual/fisiologia , Sinais (Psicologia) , Mapeamento Encefálico , Redes Neurais de Computação , Reconhecimento Visual de Modelos/fisiologia
19.
Hum Brain Mapp ; 45(3): e26605, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38379447

RESUMO

The lateral occipitotemporal cortex (LOTC) has been shown to capture the representational structure of a smaller range of actions. In the current study, we carried out an fMRI experiment in which we presented human participants with images depicting 100 different actions and used representational similarity analysis (RSA) to determine which brain regions capture the semantic action space established using judgments of action similarity. Moreover, to determine the contribution of a wide range of action-related features to the neural representation of the semantic action space we constructed an action feature model on the basis of ratings of 44 different features. We found that the semantic action space model and the action feature model are best captured by overlapping activation patterns in bilateral LOTC and ventral occipitotemporal cortex (VOTC). An RSA on eight dimensions resulting from principal component analysis carried out on the action feature model revealed partly overlapping representations within bilateral LOTC, VOTC, and the parietal lobe. Our results suggest spatially overlapping representations of the semantic action space of a wide range of actions and the corresponding action-related features. Together, our results add to our understanding of the kind of representations along the LOTC that support action understanding.


Assuntos
Lobo Occipital , Lobo Temporal , Humanos , Lobo Occipital/fisiologia , Lobo Temporal/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Mapeamento Encefálico/métodos , Estimulação Luminosa/métodos , Imageamento por Ressonância Magnética
20.
Hum Brain Mapp ; 45(3): e26616, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38379465

RESUMO

The center-periphery visual field axis guides early visual system organization with enhanced resources devoted to central vision leading to reduced peripheral performance relative to that of central vision (i.e., behavioral eccentricity effect) for many visual functions. The center-periphery organization extends to high-order visual cortex where, for example, the well-studied face-sensitive fusiform face area (FFA) shows sensitivity to central vision and the place-sensitive parahippocampal place area (PPA) shows sensitivity to peripheral vision. As we have recently found that face perception is more sensitive to eccentricity than place perception, here we examined whether these behavioral findings reflect differences in FFA's and PPA's sensitivities to eccentricity. We assumed FFA would show higher sensitivity to eccentricity than PPA would, but that both regions' modulation by eccentricity would be invariant to the viewed category. We parametrically investigated (fMRI, n = 32) how FFA's and PPA's activations are modulated by eccentricity (≤8°) and category (upright/inverted faces/houses) while keeping stimulus size constant. As expected, FFA showed an overall higher sensitivity to eccentricity than PPA. However, both regions' activation modulations by eccentricity were dependent on the viewed category. In FFA, a reduction of activation with growing eccentricity ("BOLD eccentricity effect") was found (with different amplitudes) for all categories. In PPA however, qualitatively different BOLD eccentricity effect modulations were found (e.g., at 8° mild BOLD eccentricity effect for houses but a reverse BOLD eccentricity effect for faces and no modulation for inverted faces). Our results emphasize that peripheral vision investigations are critical to further our understanding of visual processing.


Assuntos
Reconhecimento Facial , Córtex Visual , Humanos , Mapeamento Encefálico , Percepção Visual/fisiologia , Córtex Visual/diagnóstico por imagem , Córtex Visual/fisiologia , Campos Visuais , Reconhecimento Facial/fisiologia , Imageamento por Ressonância Magnética , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa
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