Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 483
Filtrar
1.
Audiol., Commun. res ; 24: e2080, 2019. tab, graf
Artigo em Português | LILACS (Américas) | ID: biblio-1011373

RESUMO

RESUMO Objetivo Avaliar a vertical visual subjetiva em indivíduos adultos jovens sem queixas vestibulares e/ou alterações do equilíbrio corporal. Método Estudo do tipo observacional, descritivo, analítico, de delineamento transversal, no qual foram avaliados 50 adultos jovens, com idade entre 18 e 30 anos. Foram excluídos do estudo indivíduos com alteração neurológica, alteração cognitiva evidente, deficiência física que influenciasse no equilíbrio corporal, alteração visual sem uso de lentes corretivas, uso de medicamentos com ação sobre o sistema nervoso central e/ou vestibular, relato de ingestão alcoólica 24 horas antes da avaliação e indivíduos com alterações e/ou queixas vestibulares. Os participantes foram submetidos à anamnese e à avaliação da vertical visual subjetiva, por meio do teste do balde. O teste foi realizado em três condições sensoriais diferentes: 1- Indivíduo sentado, com os dois pés sobre superfície estável (piso de paviflex); 2- Indivíduo sentado, com os pés em cima de uma espuma; 3- Indivíduo em pé sobre uma espuma. Resultados A vertical visual subjetiva não apresentou diferença significativa (p= 0,93) entre as condições sensoriais estudadas. Conclusão Em adultos jovens hígidos, o sistema proprioceptivo não influenciou significativamente a avaliação da vertical visual subjetiva, realizada por meio do teste do balde.


ABSTRACT Objective To evaluate subjective visual vertical in young adults without vestibular complaints and/or body balance problems. Methods This was a descriptive cross-sectional, observational and analytical study that assessed 50 young adults aged 18 to 30 years. Adult were excluded from the study if they had neurological and cognitive disorders, physical disability that affected their balance, visual impairment with no use of corrective lenses, use of drugs with effects on the central nervous system and/or the vestibular system and self-report of alcoholic use 24 hours before the assessment, and adults with vestibular problems and/or complaints The participants answered questions in a medical history interview and underwent subjective visual vertical assessment with the bucket method. The test was performed under three different sensory conditions: 1 - Subjects sitting with both feet on a stable surface (Paviflex® flooring); 2- Subjects sitting with their feet on top of foam; 3- Subjects on top of foam. Results The subjective visual vertical did not show a significant difference (p = 0.93) among the study sensory conditions. Conclusion The proprioceptive system did not significantly influence the measurement of the subjective visual vertical in young healthy adults.


Assuntos
Humanos , Adolescente , Adulto , Propriocepção , Percepção Visual , Vestíbulo do Labirinto , Vestibulopatia Bilateral/diagnóstico , Membrana dos Otólitos , Sáculo e Utrículo , Orelha Interna , Anamnese
2.
Acta Physiologica Sinica ; (6): 1-10, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wprim-777215

RESUMO

Attention shapes what we see and what we act upon by allocating limited resources to certain parts of visual display in a selective and adaptive manner. While most previous studies in visual attention mainly focused on the attentional distribution over space or features, recent studies have revealed that temporal dynamics also plays a crucial function in visual attention. This paper reviews the representation, function and neural mechanism of temporal dynamics in visual attention from the following four aspects: (1) Tracking dynamic structure of external stimulus by attention; (2) Intrinsic dynamic characteristics of attention; (3) Time-based multiple object representation; (4) Relationship between visual dynamics and classical attentional phenomena. We propose that the dynamic structure and temporal organization are fundamental to visual attention, and the research on it might provide new solutions to many unresolved issues in visual attention research.


Assuntos
Atenção , Humanos , Percepção Visual
3.
Acta Physiologica Sinica ; (6): 11-21, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wprim-777214

RESUMO

Because of a limited capacity of information processing in the brain, the efficient processing of visual information requires selecting only a very small fraction of visual inputs at any given moment in time. Attention is the main mechanism that controls this selection process, namely selective attention. Selective attention is the mechanism by which the subset of incoming information is preferentially processed from the complex external environment. Research on selective attention has two key issues. One is what targets (inputs) are selected by attention. There are three different types of selective attention according to its selected target: space-based, feature-based, and object-based attention. Another issue is how selective attention is generated. There are two different types of selective attention according to its generating source: top-down and bottom-up attention. In this review, these two issues are introduced to systematically discuss the neural mechanism of visual selective attention.


Assuntos
Atenção , Encéfalo , Fisiologia , Cognição , Humanos , Percepção Visual
4.
Acta Physiologica Sinica ; (6): 33-44, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wprim-777212

RESUMO

Integrating different visual features into a coherent object is a central challenge for the visual system, which is referred as the binding problem. Firstly, this review introduces the conception of the binding problem and the theoretical and empirical controversies regarding whether and how the binding processes are implemented in visual system. Although many neurons throughout the visual hierarchy are known to code multiple features, feature binding is recruited by visual system. Feature misbinding (or illusory conjunction) is probably the most striking evidence for the existence of the binding mechanism. Next, this review summarizes some critical issues in feature binding literature, including early binding theories, late binding theories, neural synchrony theory, the feature integration theory and re-entry processing theory. Feature binding is not a fully automatic or bottom-up processing. Reentrant connection from higher visual areas to early visual cortex (top-down processes) plays a critical role in feature binding, especially in active feature binding (i.e. feature misbinding). In addition, with electrophysiology, electroencephalography (EEG), magnetoencephalography (MEG) and transcranial electric stimulation (tEs) approaches, recent studies explored both correlational and causal relations between brain oscillations and feature binding, suggesting that brain oscillations are of great importance for feature binding. Finally, this review discusses some potential problems and open questions associated with visual feature binding mechanisms which need to be addressed in future studies.


Assuntos
Encéfalo , Fisiologia , Eletroencefalografia , Humanos , Magnetoencefalografia , Neurônios , Fisiologia , Estimulação Transcraniana por Corrente Contínua , Córtex Visual , Fisiologia , Percepção Visual
5.
Acta Physiologica Sinica ; (6): 45-52, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wprim-777211

RESUMO

The human visual system efficiently extracts local elements from cluttered backgrounds and integrates these elements into meaningful contour perception. This process is a critical step before object recognition, in which contours often play an important role in defining the shapes and borders of the to-be-recognized objects. However, the neural mechanism of the contour integration is still under debate. The investigation of the neural mechanism underlying contour integration could deepen our understanding of perceptual grouping in the human visual system and advance the development of the algorithms for image grouping and segmentation in computer vision. Here, we review two theoretical frameworks that were proposed over the past decades. The first framework is based on hardwired horizontal connection in primary visual cortex, while the second one emphasizes the role of recurrent connections within intra- and inter-areas. At the end of review, we also raise the unsolved issues that need to be addressed in future studies.


Assuntos
Percepção de Forma , Humanos , Modelos Neurológicos , Reconhecimento Visual de Modelos , Córtex Visual , Fisiologia , Percepção Visual
6.
Acta Physiologica Sinica ; (6): 53-61, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wprim-777210

RESUMO

The core of visual processing is the identification and recognition of the objects relevant to cognitive behaviors. In natural environment, visual input is often comprised of highly complex 3-dimensional signals involving multiple visual objects. One critical determinant of object recognition is visual contour. Despite substantial insights on visual contour processing gained from previous findings, these studies have focused on limited aspects or particular stages of contour processing. So far, a systematic perspective of contour processing that comprehensively incorporates previous evidence is still missing. We therefore propose an integrated framework of the cognitive and neural mechanisms of contour processing, which involves three mutually interacting cognitive stages: contour detection, border ownership assignment and contour integration. For each stage, we provide an elaborated discussion of the neural properties, processing mechanism, and its functional interaction with the other stages by summarizing the relevant electrophysiological and human cognitive neuroscience evidence. Finally, we present the major challenges for further unraveling the mechanisms of visual contour processing.


Assuntos
Cognição , Percepção de Forma , Humanos , Córtex Visual , Fisiologia , Percepção Visual
7.
Acta Physiologica Sinica ; (6): 62-72, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wprim-777209

RESUMO

Visual memory, mainly composed of visual long-term memory (VLTM) and visual working memory (VWM), is an important mechanism of human information storage. Since Baddeley proposed the multicomponent working memory model, the idea that VWM is independent of the VLTM system has been widely accepted. However, the new theoretical evidence suggested a close connection between VLTM and VWM. For instance, the three embedded components model describes the VLTM and VWM in the same framework, which suggests that VWM is only a distinct state of VLTM. On the one hand, the operating function of VWM is supported by the persistence of VLTM. On the other hand, the evidence from neuroimaging studies shows that VWM and VLTM tasks activate some same brain areas. In addition, the whole visual memory system shows a trend of processing from early visual cortex to prefrontal cortex. The present article not only reviews the current studies about the relationship between VLTM and VWM but also gives some forecasts for future studies.


Assuntos
Encéfalo , Fisiologia , Humanos , Memória de Longo Prazo , Memória de Curto Prazo , Córtex Visual , Fisiologia , Percepção Visual
8.
Acta Physiologica Sinica ; (6): 95-104, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wprim-777206

RESUMO

Recent sensory history plays a critical role in the perception of event duration. For example, repetitive exposure to a particular duration leads to the distortion of subsequent duration perception. This phenomenon, termed duration adaptation, induces a robust repulsive duration aftereffect. In particular, adaptation to relatively long sensory events shortens the perceived duration of a subsequent event, while adaptation to relatively short sensory events lengthens the perception of subsequent event durations. This phenomenon implies the plasticity of duration perception and offers important clues for revealing the cognitive neural mechanism of duration perception. Duration aftereffect has received more and more attention in recent years. In this review, we introduce recent research advances in our understanding of duration aftereffect, especially with regards to its manifestations, origin, and cognitive neural mechanisms. We also propose possible directions for future research. In sum, we posit that studies on the duration aftereffect phenomenon are helpful in understanding general duration perception, and as such, should receive more attention in future.


Assuntos
Pós-Efeito de Figura , Humanos , Percepção de Movimento , Percepção Visual
9.
Acta Physiologica Sinica ; (6): 105-116, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wprim-777205

RESUMO

To extract the temporal structure of sensory inputs is of great significance to our adaptive functioning in the dynamic environment. Here we characterize three types of temporal structure information, and review behavioral and neural evidence bearing on the encoding and utilization of such information in visual and auditory perception. The evidence together supports a functional view that the brain not only tracks but also makes use of temporal structure from diverse sources for a broad range of cognitive processes, such as perception, attention, and unconscious information processing. These functions are implemented by brain mechanisms including neural entrainment, predictive coding, as well as more specific mechanisms that vary with the type of temporal regularity and sensory modality. This framework enriches our understanding of how the human brain promotes dynamic information processing by exploiting regularities in ubiquitous temporal structures.


Assuntos
Atenção , Percepção Auditiva , Encéfalo , Fisiologia , Humanos , Percepção do Tempo , Percepção Visual
10.
Psicol. reflex. crit ; 32: 17, 2019. graf
Artigo em Inglês | LILACS (Américas), INDEXPSI | ID: biblio-1040869

RESUMO

Abstract: Background: Edge plays a special role in spatial perception and as well as in determining the brightness of a surface within borders. The aim of our study was to measure threshold brightness in different levels of edges thickness. Methods: Steven's power law for circles modulating in luminance was estimated for 30 subjects (mean age 24 years, SD 3.3, 13 female). Stimuli were presented on the iMac display using the 11-bit graphic board and consisted of two circles of 3° of visual angle, separated by 10°. We tested 7 levels of Michelson contrast: 7, 8, 10, 15, 26, 50, and 100. Three edges filtering were tested (0.3, 0.8, and 1.5° of smoothing). The subjects' task was to judge the brightness of the edge filtered circle compared with the circle of the hard edge which was considered the modulus and received an arbitrary level of 50, representing the amount of brightness perception. In each trial, the same contrast level was presented in both circles. Five judgments were performed for each contrast level in edge filtering. Results: We found an increase in the power law exponent as the increase of the edge filtering (for sigma of 0.3 = 0.43, sigma of 0.8 = 0.73, and sigma 1.5 = 0.97). All power function fitting had high correlation coefficients (r2 = .94, r2 = .95, r2 = .97, respectively to sigma 0.3, 0.8, and 1.5) passing to the model's adhesion criteria. Conclusions: There was a progressive distortion on the figure brightness perception as increasing the edge filtering suggesting the control of edges on the polarity of the overall brightness. Also, perceived brightness was increasingly veridical with increased filtering, approaching 1:1 correspondence at 1.5 sigmas. (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Percepção Visual/fisiologia
11.
Artigo em Coreano | WPRIM (Pacífico Ocidental) | ID: wprim-765427

RESUMO

PURPOSE: Patients with brain damage suffer from limitations in performing the activities of daily living (ADL) because of their motor function and visual perception impairment. The aim of this study was to help improve the motor function and visual perception ability of patients with brain damage by providing them with virtual reality-based contents. The usability results of the patients and specialists group were also evaluated. METHODS: The ADL contents consisted of living room, kitchen, veranda, and convenience store, similar to a real home environment, and these were organized by a rehabilitation specialist (e.g., neurologist, physiotherapist, and occupational therapist). The contents consisted of tasks, such as turning on the living room lights, organizing the drawers, organizing the kitchen, watering the plants on the veranda, and buying products at convenience stores. To evaluate the usability of the virtual reality-based visual cognitive rehabilitation service, general elderly subjects (n=11), stroke patients (n=7), stroke patients with visual impairment (n=4), and rehabilitation specialists (n=11) were selected. The questionnaires were distributed to the subjects who were using the service, and the subjective satisfaction of individual users was obtained as data. The data were analyzed using SPSS 21.0 software. The general characteristics of the users and the evaluation scores of the experts were analyzed using descriptive statistics. RESULTS: The usability test result of this study showed that the mean value of the questionnaire related to content understanding and difficulty was high, between 4–5 points. CONCLUSION: The virtual reality rehabilitation service of this study is an efficient service that can improve the function, interest, and motivation of stroke patients.


Assuntos
Atividades Cotidianas , Idoso , Encéfalo , Terapia Cognitivo-Comportamental , Humanos , Motivação , Fisioterapeutas , Reabilitação , Especialização , Acidente Vascular Cerebral , Transtornos da Visão , Percepção Visual , Água
12.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wprim-785332

RESUMO

Some patients with type 1 and type 2 diabetes mellitus (DM) present with cognitive dysfunctions. The pathophysiology underlying this complication is not well understood. Type 1 DM has been associated with a decrease in the speed of information processing, psychomotor efficiency, attention, mental flexibility, and visual perception. Longitudinal epidemiological studies of type 1 DM have indicated that chronic hyperglycemia and microvascular disease, rather than repeated severe hypoglycemia, are associated with the pathogenesis of DM-related cognitive dysfunction. However, severe hypoglycemic episodes may contribute to cognitive dysfunction in high-risk patients with DM. Type 2 DM has been associated with memory deficits, decreased psychomotor speed, and reduced frontal lobe/executive function. In type 2 DM, chronic hyperglycemia, long duration of DM, presence of vascular risk factors (e.g., hypertension and obesity), and microvascular and macrovascular complications are associated with the increased risk of developing cognitive dysfunction. The pathophysiology of cognitive dysfunction in individuals with DM include the following: (1) role of hyperglycemia, (2) role of vascular disease, (3) role of hypoglycemia, and (4) role of insulin resistance and amyloid. Recently, some investigators have proposed that type 3 DM is correlated to sporadic Alzheimer’s disease. The molecular and biochemical consequences of insulin and insulin-like growth factor resistance in the brain compromise neuronal survival, energy production, gene expression, plasticity, and white matter integrity. If patients claim that their performance is worsening or if they ask about the effects of DM on functioning, screening and assessment are recommended.


Assuntos
Amiloide , Processamento Eletrônico de Dados , Encéfalo , Cognição , Demência , Diabetes Mellitus , Diabetes Mellitus Tipo 2 , Estudos Epidemiológicos , Expressão Gênica , Humanos , Hiperglicemia , Hipertensão , Hipoglicemia , Insulina , Resistência à Insulina , Programas de Rastreamento , Transtornos da Memória , Neurônios , Plásticos , Maleabilidade , Pesquisadores , Fatores de Risco , Doenças Vasculares , Percepção Visual , Substância Branca
13.
Artigo em Coreano | WPRIM (Pacífico Ocidental) | ID: wprim-766821

RESUMO

Pathological tilts of the subjective visual vertical (SVV) in the roll plane are most sensitive and frequent clinical vestibular signs of unilateral lesions extending from the labyrinths via the brainstem and thalamus to the cortex. SVV deviations in cortical lesion are usually related with the parietoinsular vestibular cortex or superior temporal gyrus. We report isolated dizziness with contralesional SVV tilt with a focal infarction restricted to the right temporo-parieto-occipital junction.


Assuntos
Tronco Encefálico , Tontura , Orelha Interna , Infarto , Acidente Vascular Cerebral , Lobo Temporal , Tálamo , Percepção Visual
14.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wprim-760720

RESUMO

OBJECTIVES: The purpose of this study was to examine the combined effects of Prism Adaptation (PA) plus functional electrical stimulation (FES) on stroke patients with unilateral neglect, and suggest a new intervention method for acute-phase stroke patients. METHODS: There were 30 patients included in this study from April to October 2016 that had unilateral neglect whilst hospitalized following a stroke (diagnosed by a professional). The participants, who were patients receiving occupational therapy, understood the purpose of the study and agreed to participate. The patients were randomly divided into 3 groups: PA plus FES group (Group A), PA group (Group B), and FES group (Group C). Treatments lasted for 50 minutes per day, 5 times per week, for 3 weeks in total. Reevaluation was conducted after 3 weeks of intervention. RESULTS: All 3 groups showed unilateral neglect reduction after the intervention, but PA plus FES (complex intervention method) was more effective than PA or FES alone [effect size: Motor-free Visual Perception Test (0.80), Albert test (0.98), CBS (0.92)]. CONCLUSION: The results of this study support further studies to examine complex intervention for the treatment of unilateral neglect.


Assuntos
Estimulação Elétrica , Humanos , Métodos , Terapia Ocupacional , Acidente Vascular Cerebral , Percepção Visual
15.
Estud. interdiscip. envelhec ; 23(3): 77-93, dez. 2018. ilus
Artigo em Português | LILACS (Américas), INDEXPSI | ID: biblio-1010253

RESUMO

O objetivo desta pesquisa foi avaliar a percepção de diferentes preparações gastronômicas entre idosos. Participaram desta pesquisa 38 idosos (idade = 67,65, DP = ± 6,15), que degustaram uma preparação montada de duas formas, uma mais e outra menos estética. Esses idosos responderam a um questionário semiestruturado para os dados sociodemográficos, além de medidas hedônicas relacionadas às preparações e medidas psicológicas para avaliação dos estados de humor. Para análise dos dados, foram utilizados os testes Shapiro-Wilks, Wilcoxon, Mann Whitney e Kruskal-Wallis. Além disso, optou-se por trabalhar com o delta da diferença com três grupos, de acordo com a sua preferência de prato, utilizando o teste Qui-Quadrado (Monte Carlo). Os resultados demonstraram que o prato mais estético foi melhor avaliado por todos os idosos (p = 0,000), que o prato mais estético foi percebido como maior quantidade de sal quando dividido por faixa etária (p = 0,020), não havendo diferença entre idosos e idosas (p ≥ 0,05). Também não foram encontradas diferenças quanto às percepções pelo fato de o idoso cozinhar ou não, tampouco pela presença de ansiedade e depressão, visto que o grupo tinha baixos escores dessas. Assim, a utilização de pratos mais estéticos na gastronomia pode vir a favorecer a melhora do comportamento alimentar neste grupo, assim como melhorar a percepção de gostos, especialmente do salgado, que é diminuído no processo de envelhecer. (AU)


The objective of this research was to evaluate the perception of different gastronomic preparations among the elderly. Thirty-eight elderly (age = 67.65, SD = ± 6.15) participated in this study, who tasted a preparation assembled in two ways, one more and one less aesthetic. Those elderly filled in a semi-structured questionnaire for sociodemographic data, as well as hedonic measures related to the preparation and psychological measures to assess mood states. For data analysis, the Shapiro-Wilks, Wilcoxon, Mann Whitney and Kruskal-Wallis tests were used. In addition, we chose to work with the difference delta with three groups, according to their plate preference, using the Chi-square test (Monte Carlo). The results showed that the most aesthetic dish was better evaluated by all the elderly (p = 0.000), that the more aesthetic dish was perceived as having a greater amount of salt when divided by age group (p = 0.020), and that there was no difference between elderly men and elderly women (p ≥ 0.05). Also, no differences on perceptions were found regarding the fact of whether the elderly cooked or not, as well as whether they had anxiety and depression, since the group had low anxiety and depression scores. Thus, the use of more aesthetic dishes in the gastronomy may favor the improvement of the food behavior in this group, as well as improve the perception of tastes, especially the salty one, that is diminished in the aging process. (AU)


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Percepção Visual , Estética/psicologia , Comportamento Alimentar/psicologia , Preferências Alimentares , Ansiedade/epidemiologia , Estudos Transversais , Fatores Etários , Culinária , Depressão/epidemiologia
16.
Arq. bras. psicol. (Rio J. 2003) ; 70(3): 274-288, set./dez. 2018.
Artigo em Português | LILACS (Américas), INDEXPSI | ID: biblio-986771

RESUMO

A ilusão da máscara côncava ocorre quando o observador a determinada distância percebe uma máscara facial côncava como convexa. Isso pode ser explicado pela sobreposição dos processos de alta ordem da percepção visual sobre os de baixa ordem. Pesquisas com indivíduos intoxicados e em Síndrome de Abstinência do Álcool (SAA) revelaram um prejuízo em perceber essa ilusão. O objetivo foi realizar uma revisão da literatura sobre o tema. Após buscas em bases indexadas, cinco pesquisas foram encontradas. Os resultados para os alcoolistas em SAA moderada revelaram uma menor frequência nas respostas de percepção da ilusão. Os resultados foram contraditórios quanto ao grupo de alcoolistas com SSA leve. Pesquisas futuras com metodologias diferentes são necessárias para testar as hipóteses explicativas da ilusão da máscara côncava em alcoolistas. É importante considerar os processos de tomada de decisão do observador diante da observação dos objetos como base a Teoria de Detecção de Sinal (TDS)


The hollow-face illusion happens when the observer perceives a concave facial mask as convex, at a given distance. This can be explained by the overlap of top-down on bottom-up visual processes. Researches demonstrated that intoxicated and Alcohol Withdrawal Syndrome (AWS) individuals had deficit in perceiving this illusion. This study aimed to review the literature on this topic. A survey of indexed databases found five studies. The results for alcoholics with moderate AWS were similar and showed a lower frequency in the answers of illusion perception. However, results were contradictory to the alcoholic group with mild AWS. Future researches with different methodologies are necessary to test the hollow-face illusion hypotheses in alcoholics. Therefore, it is also important to consider the observer's decision-making processes in the objects observation based on the Signal Detection Theory (SDT)


La ilusión de la máscara cóncava ocurre cuando el observador a cierta distancia percibe una máscara facial cóncava como convexa. Esto puede ser explicado por la superposición de los procesos de alto orden de la percepción visual sobre los de bajo orden. Las investigaciones con individuos intoxicados y en el Síndrome de Abstinencia del Alcohol (SAA) revelaron un perjuicio en percibir esa ilusión. El objetivo fue realizar una revisión de la literatura sobre el tema. Después de buscar en bases indexadas, se encontraron cinco encuestas. Los resultados para los alcohólicos en SAA moderada revelaron una menor frecuencia en las respuestas de percepción de la ilusión. Los resultados fueron contradictorios en cuanto al grupo de alcohólicos con SSA leve. Las investigaciones futuras con metodologías diferentes son necesarias para probar las hipótesis explicativas de la ilusión de la máscara cóncava en alcohólicos. Es importante considerar los procesos de toma de decisión del observador ante la observación de los objetos como base la Teoría de Detección de Señal (TDS)


Assuntos
Ilusões Ópticas , Síndrome de Abstinência a Substâncias , Percepção Visual , Alcoolismo
17.
Arq. bras. psicol. (Rio J. 2003) ; 70(2): 251-265, maio/ago. 2018.
Artigo em Português | LILACS (Américas), INDEXPSI | ID: biblio-981528

RESUMO

A ilusão da máscara côncava ocorre quando o observador a determinada distância percebe uma máscara facial côncava como convexa. Isso pode ser explicado pela sobreposição dos processos de alta ordem da percepção visual sobre os de baixa ordem. Pesquisas com indivíduos intoxicados e em Síndrome de Abstinência do Álcool (SAA) revelaram um prejuízo em perceber essa ilusão. O objetivo foi realizar uma revisão da literatura sobre o tema. Após buscas em bases indexadas, cinco pesquisas foram encontradas. Os resultados para os alcoolistas em SAA moderada revelaram uma menor frequência nas respostas de percepção da ilusão. Os resultados foram contraditórios quanto ao grupo de alcoolistas com SSA leve. Pesquisas futuras com metodologias diferentes são necessárias para testar as hipóteses explicativas da ilusão da máscara côncava em alcoolistas. É importante considerar os processos de tomada de decisão do observador diante da observação dos objetos como base a Teoria de Detecção de Sinal (TDS)


The hollow-face illusion happens when the observer perceives a concave facial mask as convex, at a given distance. This can be explained by the overlap of top-down on bottom-up visual processes. Researches demonstrated that intoxicated and Alcohol Withdrawal Syndrome (AWS) individuals had deficit in perceiving this illusion. This study aimed to review the literature on this topic. A survey of indexed databases found five studies. The results for alcoholics with moderate AWS were similar and showed a lower frequency in the answers of illusion perception. However, results were contradictory to the alcoholic group with mild AWS. Future researches with different methodologies are necessary to test the hollow-face illusion hypotheses in alcoholics. Therefore, it is also important to consider the observer's decision-making processes in the objects observation based on the Signal Detection Theory (SDT)


La ilusión de la máscara cóncava ocurre cuando el observador a cierta distancia percibe una máscara facial cóncava como convexa. Esto puede ser explicado por la superposición de los procesos de alto orden de la percepción visual sobre los de bajo orden. Las investigaciones con individuos intoxicados y en el Síndrome de Abstinencia del Alcohol (SAA) revelaron un perjuicio en percibir esa ilusión. El objetivo fue realizar una revisión de la literatura sobre el tema. Después de buscar en bases indexadas, se encontraron cinco encuestas. Los resultados para los alcohólicos en SAA moderada revelaron una menor frecuencia en las respuestas de percepción de la ilusión. Los resultados fueron contradictorios en cuanto al grupo de alcohólicos con SSA leve. Las investigaciones futuras con metodologías diferentes son necesarias para probar las hipótesis explicativas de la ilusión de la máscara cóncava en alcohólicos. Es importante considerar los procesos de toma de decisión del observador ante la observación de los objetos como base la Teoría de Detección de Señal (TDS)


Assuntos
Humanos , Ilusões Ópticas , Síndrome de Abstinência a Substâncias , Percepção Visual , Alcoolismo
18.
Memorandum ; 34: 14-32, jun. 2018.
Artigo em Português | LILACS (Américas) | ID: biblio-913980

RESUMO

Propõe-se a análise de aspectos da teoria de Hermann von Helmholtz sobre a percepção espacial a fim de destacar algumas tensões básicas que constituem o cenário de seu projeto científico. Sugere-se que a sua teoria da percepção encerra a problemática da coexistência de duas estratégias metodológicas distintas para a investigação da percepção espacial e para a elaboração de sua epistemologia empírica. Para solucionar a aparente dicotomia metodológica de dois tipos de estudos e avançar a sua própria teoria da percepção e a sua epistemologia, Helmholtz parece ter adotado a estratégia de naturalizar muitos dos problemas transcendentais provenientes da filosofia kantiana. Apresenta-se, então, em um primeiro momento, os fundamentos metodológicos das pesquisas psicofísicas de Helmholtz. Na sequência, são apresentados e discutidos alguns temas exemplares de seu método de análise e de sua teoria da percepção espacial. Por fim, são fornecidos alguns comentários sobre a sua epistemologia empirista.(AU)


An analysis of some aspects of Hermann von Helmholtz's theory of spatial perception is proposed in order to highlight some basic tensions which constitute the scenario of his scientific project. It is suggested that his theory of perception contains the problematic of the coexistence of two distinct methodological strategies for the investigation of spatial perception and for the elaboration of his empirical epistemology. In order to solve the apparent methodological dichotomy of two types of studies and to advance on his own theory of perception and epistemology, it seems Helmholtzadopted the strategy of naturalizing many of the transcendental problems arising from Kantian Philosophy. Thus, in a first moment, the methodological foundations of the Psychophysical investigations of Helmholtz are presented. In sequence, some examples of his method of analysis and his theory of spatial perception are presented and analyzed. Finally, some comments are provided in respect of his empiricist epistemology.(AU)


Assuntos
Psicologia , Psicofísica , Percepção Visual
19.
Cienc. act. fís. (Talca, En línea) ; 19(1): 1-7, ene. 2018. ilus, graf
Artigo em Espanhol | LILACS (Américas) | ID: biblio-986535

RESUMO

El objetivo de este estudio ha sido evaluar la habilidad perceptiva cognitiva de los deportistas seleccio-nados de la Universidad de Playa Ancha a través de una herramienta tecnológica de seguimiento de objetos múltiples dentro de un campo visual (Neurotracker). Se utilizó una metodología de carácter cuantitativo enmarcado dentro del paradigma positivista de tipo descriptivo. La muestra fue de 101 deportistas de diversas disciplinas y ambos sexos, todos escogidos a través del método de muestreo por conveniencia o selección intencionada. Los datos obtenidos fueron analizados a través de estadística descriptiva inferencial. Los resultados muestran que la clasificación del deporte (estructura abierta y estructura cerrada) influencia el rendimiento perceptivo-cognitivo del deportista, existiendo una estricta relación con las horas de entrenamiento. Ambas variables son directamente proporcional a los resultados y, se presentan diferencias significativas según sexo.


The objective of this study was to evaluate the cognitive-perceptive ability of selected athletes from Universidad Playa Ancha by means of a technological tracking tool for multiple objects within a visual field (Neurotracker). The researchers applied quantitative methods based on the positivist paradigm of descriptive type. The sample size consisted of 101 female and male athletes from various majors, all of whom were selected through the convenience sampling method. The data was analyzed using infe-rential descriptive statistics. The study results demonstrate that the sports classification (open struc-ture and closed structure) influences the perception/cognitive performance of the athletes, showing a strong relationship to the number of hours of athletic training. Both variables were found to be directly proportional to the results and there were significant differences based on sex/gender


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Esportes , Percepção Visual/fisiologia , Campos Visuais , Atletas , Estudos Transversais , Testes de Campo Visual
20.
Braz. j. med. biol. res ; 51(3): e6568, 2018. tab, graf
Artigo em Inglês | LILACS (Américas) | ID: biblio-889051

RESUMO

The goal of this study was to compare the visual contrast sensitivity (CS) of men and women exposed and not exposed to organic solvents. Forty-six volunteers of both genders aged between 18 and 41 years (mean±SD=27.72±6.28) participated. Gas station attendants were exposed to gas containing 46.30 ppm of solvents at a temperature of 304±274.39 K, humidity of 62.25±7.59% and ventilation of 0.69±0.46 m/s (a passive gas chromatography-based sampling method was used considering the microclimate variables). Visual CS was measured via the psychophysical method of two-alternative forced choice using vertical sinusoidal gratings with spatial frequencies of 0.2, 0.5, 1.0, 2.0, 5.0, 10.0, and 16.0 cpd (cycles per degree) and an average luminance of 34.4 cd/m2. The results showed that visual CS was significantly lower (P<0.05) in the following groups: i) exposed men compared to unexposed men at frequencies of 0.2, 0.5, 1.0, and 2.0 cpd; ii) exposed women compared to unexposed women at a frequency of 5.0 cpd; and iii) exposed women compared to exposed men at a frequency of 0.5 cpd, even at exposures below the tolerance limit (300 ppm). These results suggest that the visual CS of exposed men was impaired over a wider range of spatial frequencies than that of exposed women. This difference may have been due to the higher body fat content of women compared to that of men, suggesting that body fat in women can serve as a protective factor against neurotoxic effects.


Assuntos
Humanos , Masculino , Feminino , Adulto , Adulto Jovem , Sensibilidades de Contraste/efeitos dos fármacos , Exposição Ocupacional/efeitos adversos , Solventes/efeitos adversos , Percepção Visual/fisiologia , Tecido Adiposo/anatomia & histologia , Brasil/epidemiologia , Escolaridade , Microclima , Exposição Ocupacional/estatística & dados numéricos , Limiar Sensorial/fisiologia , Fatores Sexuais , Aprendizagem Espacial/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA