Search and Match Task: Development of a Taskified Match-3 Puzzle Game to Assess and Practice Visual Search.

BACKGROUND: Visual search declines with aging, dementia, and brain injury and is linked to limitations in everyday activities. Recent studies suggest that visual search can be improved with practice using computerized visual search tasks and puzzle video games. For practical use, it is important that visual search ability can be assessed and practiced in a controlled and adaptive way. However, commercial puzzle video games make it hard to control task difficulty, and there are little means to collect performance data. OBJECTIVE: The aim of this study was to develop and initially validate the search and match task (SMT) that combines an enjoyable tile-matching match-3 puzzle video game with features of the visual search paradigm (taskified game). The SMT was designed as a single-target visual search task that allows control over task difficulty variables and collection of performance data. METHODS: The SMT is played on a grid-based (width × height) puzzle board, filled with different types of colored polygons. A wide range of difficulty levels was generated by combinations of 3 task variables over a range from 4 to 8 including height and width of the puzzle board (set size) and the numbers of tile types (distractor heterogeneity). For each difficulty level, large numbers of playable trials were pregenerated using Python. Each trial consists of 4 consecutive puzzle boards, where the goal of the task is to find a target tile configuration (search) on the puzzle board and swap 2 adjacent tiles to create a line of 3 identical tiles (match). For each puzzle board, there is exactly 1 possible match (single target search). In a user study with 28 young adults (aged 18 to 31 years), 13 older (aged 64 to 79 years) and 11 oldest (aged 86 to 98 years) adults played the long (young and older adults) or short version (oldest adults) of the difficulty levels of the SMT. Participants rated their perception and the usability of the task and completed neuropsychological tests that measure cognitive domains engaged by the puzzle game. RESULTS: Results from the user study indicate that the target search time is associated with set size, distractor heterogeneity, and age. Results further indicate that search performance is associated with general cognitive ability, selective and divided attention, visual search, and visuospatial and pattern recognition ability. CONCLUSIONS: Overall, this study shows that an everyday puzzle game-based task can be experimentally controlled, is enjoyable and user-friendly, and permits data collection to assess visual search and cognitive abilities. Further research is needed to evaluate the potential of the SMT game to assess and practice visual search ability in an enjoyable and adaptive way. A PsychoPy version of the SMT is freely available for researchers.

Nonverbal Memory Capacity in Persons with Epilepsy Is Associated with Depression Rather than Anxiety.

Epilepsy is characterized by repeated epileptic seizures, which are manifested in various ways and depend on the location and size of foci in the brain. Long-term seizures with secondary generalization can cause memory problems. Numerous studies demonstrate the connection of memory damage and lateralization in medial temporal lobe epilepsy (TLE). However, the results were not always consistent with the material-specific memory model. A possible explanation for these inconsistent data is the insufficient control of psychological variables that can affect memory. In most of the previous studies in persons with epilepsy, they were not controlled for their emotional states such as anxiety and depression. We used the Rey Complex Figure Test (RCFT) as a measure of visual memory, Beck's depression inventory as a measure of depressive symptoms, and the State-Trait Anxiety Inventory as a measure of anxiety in 57 consecutive participants. Our aim was to investigate whether there is difference in visual memory with respect to the left and right TLE, and whether the participants of different gender with higher anxiety and depression rates would achieve different results on visual memory. Persons with lower levels of depression achieved better scores in the Immediate and Delayed recall subtests of the RCFT. We also explored the potential gender differences. Testing differences between the persons with higher and lower anxiety levels did not reveal any significant differences in any of the measures tested.

Pattern-reversal visual evoked potentials as a diagnostic tool for ocular malingering / Potenciais visuais evocados por padrões reversos como uma ferramenta diagnóstica de simulação

ABSTRACT Purpose: To investigate the contributions of transient pattern-reversal visual evoked potentials in the diagnosis of ocular malingering at a Brazilian university hospital. Methods: Adult patients with suspected malingering in one or both eyes were referred for visual evoked potential testing. Data from patients' medical records were reviewed and analyzed retrospectively. Data analysis included the distance optotype visual acuity based on a ETDRS retro-illuminated chart and the transient pattern-reversal visual evoked potential parameters of latency (milliseconds) and amplitude (microvolts) for the P100 component, using checkerboards with visual subtenses of 15' and 60'. Motivations for malingering were noted. Results: The 20 subjects included 11 (55%) women. Patient ages ranged from 21 to 61 years (mean= 45.05 ± 11.76 years; median= 49 years). In 8 patients (6 women), both eyes exhibited reduced visual acuity with normal pattern-reversal visually evoked potential parameters (pure malingerers). The remaining 12 patients (7 men) exhibited reduced vision in only 1 eye, with simulated reduced vision in the contralateral eye (exaggerators). Financial motivation was noted in 18 patients (9 men). Conclusion: Normal pattern-reversal visually evoked potential parameters with suspected ocular malingering were observed in a 20 patient cohort. This electrophysiological technique appeared to be useful as a measure of visual pathway integrity in this specific population.

RESUMO Objetivo: Investigar a contribuição dos potenciais visuais evocados por padrões reversos no diagnóstico de simulação de baixa de visão em um hospital universitário do Brasil. Métodos: Um grupo de pacientes adultos com suspeita de simulação de baixa de visão em um ou ambos os olhos foi avaliado e os dados analisados retrospectivamente. Foram medidos: acuidade visual de optotipos informada para longe utilizando a tabela ETDRS, parâmetros dos potenciais visuais evocados por padrões reversos de latência (milissegundos) e amplitude (microvolts) para o componente P100 com estímulos de ângulos visuais de 15' e 60'. A motivação do paciente para a simulação foi anotada. Resultados: Os participantes foram 20 indivíduos com 11 (55%) do sexo feminino. A idade variou de 21 a 61 anos (média= 45,05 ± 11,76 anos; mediana= 49 anos). Em 8 pacientes (6 mulheres) ambos os olhos tinham acuidade visual reduzida com parâmetros dos potenciais visuais evocados por padrão reverso normais para ambos os olhos (simuladores puros). Uma subsérie separada de 12 pacientes (7 homens) tinha visão reduzida em apenas um olho e estavam simulando redução da visão no outro olho (exacerbadores). A motivação financeira foi observada em 18 pacientes (9 homens). Conclusões: Parâmetros dos potenciais visuais evocados por padrões reversos normais foram encontrados neste grupo de 20 pacientes com suspeita de simulação. Esta técnica eletrofisiológica pode ser útil como uma medida da integridade do sistema visual nesta população de doentes.

The clothes maketh the sign.

UNLABELLED: Pattern recognition is a key tool that enables radiologists to evoke certain diagnoses based on a radiologic appearance. In Shakespeare's Hamlet, Polonius tells his son Laertes to dress well because "apparel oft proclaims the man"; this phrase is now expressed in modern parlance as "the clothes maketh the man". Similarly in radiology, appearances are everything, and in the case of radiologic signs, occasionally "the clothes maketh the sign". The radiologic signs described in this pictorial review resemble items of clothing, fabric types, headwear, or accessories and are found in the musculoskeletal, pulmonary, gastrointestinal, and genitourinary systems. These "clothing signs" serve as a useful visual trigger to help radiologists to identify particular disease entities. TEACHING POINTS: • Pattern recognition enables radiologists to evoke a diagnosis based on radiologic appearance. • The radiologic signs described in this review resemble clothing, fabric, or accessories. • These "clothing signs" serve as visual triggers that evoke particular disease entities.

Effect of monocular depth perception on accommodative response / 中华实验眼科杂志

Background Different depthes or distances are prompted with many visual cues on the flat screen.Which kind of depth cues plays a major role in the accommodation of human eyes,in addition,whether this effect exists in the different distance are still below understood.Objective This study was to research the effect of the monocular space depth perception on accommodative response at different distances,and to analyze the effect of linear perspective and size-constancy perceptual depth cues on the level and amplitude of accommodative fluctation.Methods Four groups of visual targets were designed by FLASH software and placed at the front of eyes with the distance of 50 cm or 33.3 cm,representing static change from far to near and dynamic change from far to near,from near to far respectively.Twenty-six healthy volunteers aged 22-26 years were included in this study,with the spherical power of (-4.06± 1.99) D and cylindrical power of (-0.38±0.41) D under the informed consent.The accommodative response and accommodative fluctuations during monocularly watching the targets were recorded at 5 times/second by Grand Seiko WAM 5500 automatic infrared refractor.This study was approved by Ethic Committee of Wenzhou Medical University,and written informed consent was obtained from each subject before entering the study group.Results At the distance of 50 cm,the accommodative response caused by the depth perception of near was (1.52±0.46) D,the one of distance was (1.37±0.46) D,with a significant difference of 0.15 D under the combined effect of linear perspective and size-constancy (P =0.016).The accommodative response caused by the depth perception of big car was (1.43 ± 0.35) D,and the one of small car was (1.43 ± 0.36) D,without statistically significant difference under the effect of size-constancy alone (P =0.467).At the distance of 33.3 cm,the accommodative response caused by the depth perception of near was (2.40±0.53)D,and the one of distance was (2.35 ±0.51) D,without significant difference under the combined effect of linear perspective and size-constancy (P=0.379).The accommodative response caused by the depth perception of big car was (2.38±0.48)D,the one of small car was (2.39±0.52)D,without statistically significant difference under the effect of size-constancy alone (P =0.820).In addition,the total curve of accommodative microfluctuation showed apparent fluctuation periodically caused by the distance perception involving linear perspective only.Conclusions Monocular space depth perception has some impacts on the accommodative response at certain distance.Linear perspective,which is one of the depth cues of space perception,plays a major role in the accommodative response.Compared with the size-constancy,linear perspective can provide depth perception at higher level.The size-constancy has a little or contrast impact to the accommodation,because it depends on the assistance from other depth cues like linear perspective.

Individuals with 22q11.2 deletion syndrome are impaired at explicit, but not implicit, discrimination of local forms embedded in global structures.

Individuals with 22q11.2 deletion syndrome (22q11.2DS) are impaired at exploring visual information in space; however, not much is known about visual form discrimination in the syndrome. Thirty-five individuals with 22q11.2DS and 41 controls completed a form discrimination task with global forms made up of local elements. Affected individuals demonstrated clear impairment in detecting local, but not global, differences. Nevertheless, 22q11.2DS participants easily discriminated the same local elements when they were displayed in isolation, and further use of a prime demonstrated preserved facilitation of local processing in 22q11.2DS. These results did not differ by age or IQ. This study illustrates the impact of visuospatial impairments on form discrimination, and suggests how these difficulties may affect visual scanning in 22q11.2DS.

Pattern-reversal electroretinograms for the diagnosis and management of disorders of the anterior visual pathway / Eletroretinograma de padrão reverso no diagnóstico e acompanhamento das afecções da via óptica anterior

The pattern electroretinogram is an electrophysiological test that assesses the function of inner retinal layers, particularly the ganglion cells layer of retina, using a reversing checkerboard or grating pattern that produces no change in average luminance over time. The normal pattern electroretinogram is composed of a proeminent positive component (P50) and a large later negative component (N95). Since structural damage that compromises the retinal ganglion cell layer can lead to pattern electroretinogram changes, particularly in the N95 amplitude, the test can be useful in the treatment of a number of anterior visual pathway diseases. In this article, we review the methods for recording pattern electroretinogram and its usefulness in the diagnosis and management of diseases including inflammatory, hereditary, ischemic and compressive lesions of the anterior visual pathway.

O eletroretinograma de padrão reverso é um teste eletrofisiológico que avalia a função das camadas internas da retina, especialmente a camada de células ganglionares, através de um estímulo em xadrez ou em barras que não apresenta variação na luminância do estímulo. É composto de um componente positivo (P50) e um componente negativo (N95) tardio. Uma vez que lesões estruturais às células ganglionares da reitna podem levar a alterações no eletroretinograma de padrão reverso, especialmente na amplitude da onda N95, o teste pode ser útil no tratamento de várias doenças da via óptica anterior. Neste artigo revisamos os métodos de obtenção do eletroretinograma de padrão reverso e a sua utilidade no diagnóstico e acompanhamento de doenças incluindo lesões inflamatórias, hereditárias, isquemicas e compressivas na via óptica anterior.

Medida da visão em candelas: description of a psychophysical technique to quantify luminous intensity / descrição de uma técnica psicofísica para quantificar intensidade luminosa / Vision measurement in candelas

OBJETIVO: Desenvolver um método e um dispositivo para quantificar a visão em candela (cd). Os estudos de medida da visão são importantes para todas as ciências visuais. MÉTODOS: É um estudo teórico e experimental. Foram descritos os detalhes do método psicofísico e da calibração do dispositivo. Foram realizados testes preliminares em voluntários. RESULTADOS: É um teste psicofísico simples e com resultado expresso em unidades do sistema internacional de medidas. Com a descrição técnica será possível reproduzir o experimento em outros centros de pesquisa. CONCLUSÃO: Os resultados aferidos em intensidade luminosa (cd) são uma opção para estudo visual. Esses resultados possibilitarão extrapolar medidas para modelos matemáticos e para simular efeitos individuais com dados aberrométricos.

PURPOSE: To develop a method and a device for vision measurement in candela (cd). Vision measurement studies are important to all visual sciences. METHODS:It is a theoretical and experimental study. The details of psychophysical method and device calibration were described. Preliminary tests were performed on volunteers. RESULTS:It is a simple psychophysical test and results are expressed in International System of Units. With this technical description it will be possible to reproduce the experiment in others research centers. CONCLUSION: The results measured in luminous intensity (cd) are an option for visual studies. These results allow to extrapolate measurements for mathematical models and to simulate data for individual aberrometry effects.

Prism adaptation for unilateral spatial neglect / 国际脑血管病杂志

Unilateral spatial neglect is an important factor for affecting the brain damage,especially in patients with functional recovery after stroke.Seeking for the effective rehabilitation measles of unilateral spatial neglect has an important significance for improving the quality of life in patients.Currently,prism adaptation is the most widely used and well-studied treatment for unilateral spatial neglect,however,there is less domestic research in this field.This article reviews the advances in research on the therapeutic mechanism of prism adaptation for unilateral spatial neglect,the application in unilateral spatial neglect after stroke as well as its efficacy.

Figura ambígua e dislexia do desenvolvimento / Ambiguous figure and developmental dyslexia

OBJETIVO: Avaliar o processamento visual de figuras ambíguas em indivíduos disléxicos e compará-lo a um grupo controle leitor normal. MÉTODOS: Survey comparativo onde foram selecionados aleatoriamente 39 escolares cursando entre a primeira e a quarta série do ensino fundamental. Deste total, 26 não apresentavam dificuldade de leitura ou mau rendimento escolar e constituíram o grupo controle. As outras 13 crianças (grupo de estudo) eram portadoras de Dislexia do desenvolvimento. Foram apresentadas, pela ordem, uma figura de Boring, uma figura com vasos de Rubin e uma figura pato/coelho de Jastrow. RESULTADOS: Os resultados obtidos mostram que as crianças com diagnóstico de Dislexia do desenvolvimento perceberam número menor de figuras em relação às do grupo controle. CONCLUSÃO: O exame do processamento visual de crianças com Dislexia do desenvolvimento para figuras ambíguas é alterado quando comparado ao de crianças leitoras normais.

OBJECTIVE: Evaluate the visual response of children with developmental dyslexia when ambiguous figure was presented in comparison with normal readers children. METHODS: 39 children from basic school was randomly chosen. 26 were normal readers. 13 were diagnosed developmental dyslexia.Were presented the Boring figure, Rubin vessels figure and Jastrow figure. RESULTS: Participants in the clinical group with dyslexia performed marginally less well than those in the control group. CONCLUSION: The visual response of children with developmental dyslexia when ambiguous figure was presented is less well in comparison with normal readers children.

Medida da visão e testes psicofísicos / Vision measurement and psychophysical tests

A medida da visão é a base para o estudo e a padronização das ciências visuais. A medida da acuidade visual tem grande importância tanto para a pesquisa como para a prática clínica. Esta revisão bibliográfica (1) revê os conceitos fundamentais para compreender o sentido visual e as unidades de medida; (2) apresenta os limites fundamentais ao desempenho visual e os princípios das medidas da aberração ocular; e (3) discute métodos para medir e classificar a visão com novas tecnologias.

Vision measurement is the basis for the study and standardization of visual sciences. Measurement of visual acuity has great value for research and for clinical practice. This paper (1) reviews the fundamental concepts to understand visual sense and the measuring units; (2) presents the fundamental limits to visual performance and the principles of aberration measurement of the eye; and (3) discusses methods for measuring and classifying vision with new technologies.

Análise dos padrões dos movimentos oculares em tarefas de busca visual: efeito da familiaridade e das características físicas do estímulo / Analysis of the eye movement patterns in visual search tasks: effect of familiarity and stimulus features

OBJETIVOS: Analisar os movimentos oculares numa tarefa de busca visual assimétrica com letras normais e espelhadas. Explorar o efeito da familiaridade e características do estímulo. MÉTODOS: Oitenta e três universitários emétropes ou com correção óptica foram solicitados a procurar por uma letra normal ou espelhada, num contexto de letras espelhadas ou normais, respectivamente. Foram utilizados quatro tipos de letras (Z, N, E e G) e os movimentos dos olhos foram rastreados por meio de um sistema computacional especializado (eyetracking). As medidas utilizadas para análise foram: tempo de reação, duração e número de fixações, duração e distância dos movimentos sacádicos. RESULTADOS: A análise em função do tipo de letra mostrou diferenças para todas as medidas. O tempo de reação, o número de fixações e a distância média dos movimentos sacádicos foram maiores para encontrar uma letra normal em um conjunto de letras espelhadas. A duração média das fixações, entretanto, foi menor nessa situação. Houve interação dupla entre espelhamento e tipo de letra para o tempo de reação, duração média e número de fixações. O tempo de reação e o número de fixações apresentam função crescente de acordo com o grau de complexidade do estímulo, com aumento acentuado na situação em que o alvo é a letra normal. A duração das fixações, por sua vez, diminui em função da complexidade do estímulo e da situação. CONCLUSÕES: Foi mais fácil encontrar uma letra espelhada entre as normais, que o oposto, sendo que o desempenho também sofreu influência do tipo de letra. Quando o contexto é formado por estímulos não familiares e complexos, a duração média das fixações é menor, indicando um processamento visual com amplitude reduzida. Desta forma, são necessárias mais fixações com menor duração para um contexto não familiar e menos fixações com maior duração, para o familiar.

PURPOSE: To analyze eye movements in asymmetric visual search using the task of normal and mirrored position letters. To evaluate the effect of familiarity and stimulus features. METHODS: Eighty-three university students with normal or corrected-to-normal vision were asked to search for a letter in inverted position to the letters in a group of either normal or mirrored letters. Four types of letters were used (Z, N, E and G) and the eye movements were tracked by a specialized computer-based system (eyetracking). The analyzed measurements were: reaction time, fixation number and duration, saccade distance and duration. RESULTS: All measures varied with the type of letter. Reaction time, fixation number, and saccade distance were higher when the task was to find the normal letter in a group of mirrored letters. In this condition, fixation duration was smaller. Interaction was found between familiarity and the type of letter for the reaction time, fixation number and duration. The reaction time and fixation number increased together with the stimulus complexity, with a greater increase for the normal letter target. Fixation duration, however, decreased with the complexity of the stimuli and the search condition. CONCLUSIONS: Finding a mirrored letter among normal letters proved to be easier than the contrary. The letter type also affected the performance. When the context is formed of unfamiliar complex stimuli, the fixation duration is shorter, indicating a narrower span for visual processing. Therefore, a greater number of fixations with shorter duration are needed for the unfamiliar context while less fixations with greater duration are needed for the familiar context.