Um Retrato da Área de Neurociência e Comportamento no Brasil

Neuroscience comprises the study of the neural control of vegetative, sensory and motor functions; of the locomotion, reproduction and feeding behaviors; and of the mechanisms of attention, memory, learning, emotion, language and communication. It has, therefore, an important area of interface with Psychology. Among its goals, neuroscience seeks to explain the mechanisms of neurologic and mental diseases through the study of the normal and pathologic nervous system. Its evolution in Brazil has occurred since the middle of the past century, and its development was encouraged by the creation of specific scientific societies. The present article describes this development and the main active groups in Brazilian neuroscience.  A neurociência compreende o estudo do controle neural das funções vegetativas, sensoriais e motoras; dos comportamentos de locomoção, reprodução e alimentação; e dos mecanismos da atenção, memória, aprendizagem, emoção, linguagem e comunicação. Tem, portanto, uma importante área de interface com a Psicologia. Dentre seus objetivos, a neurociência busca esclarecer os mecanismos das doenças neurológicas e mentais por meio do estudo do sistema nervoso normal e patológico. Sua evolução no Brasil tem ocorrido desde meados do século passado, e seu desenvolvimento foi incentivado pela criação de sociedades científicas específicas. O presente artigo relata esse desenvolvimento e descreve os principais grupos atuantes na neurociência brasileira. &nbsp

Psychophysical measurements of luminance and chromatic spatial and temporal contrast sensitivity in Duchenne muscular dystrophy

In children with Duchenne muscular dystrophy, color vision losses have been related to dystrophin deletions downstream of exon 30, which affect a dystrophin isoform, Dp260, present in the retina. To further evaluate visual function in DMD children, we measured spatial, temporal, and chromatic red-green and blue-yellow contrast sensitivity in two groups of DMD children with gene deletion downstream and upstream of exon 30. Psychophysical spatial contrast sensitivity was measured for low, middle, and high spatial frequencies with achromatic gratings and for low and middle frequencies with red-green and blue-yellow chromatic gratings. Temporal contrast sensitivity was also measured with achromatic stimuli. A reduction in sensitivity at all spatial luminance contrasts was found for the DMD patients with deletion downstream of exon 30. Similar results were found for temporal luminance contrast sensitivity. Red-green chromatic contrast sensitivity was reduced in DMD children with deletion downstream of exon 30, whereas blue-yellow chromatic contrast sensitivity showed no significant differences. We conclude that visual function is impaired in DMD children. Furthermore, we report a genotype-phenotype relationship because the visual impairment occurred in children with deletion downstream but not upstream of exon 30, affecting the retinal isoform of dystrophin Dp260.FAPESPConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Visual impairment in children with spastic cerebral palsy measured by psychophysical and electrophysiological grating acuity tests

Background: This study measured grating visual acuity in 173 children between 6-48 months of age who had different types of spastic cerebral palsy (CP). Method: Behavioural acuity was measured with the Teller Acuity Cards (TAC) using a staircase psychophysical procedure. Electrophysiological visual acuity was estimated using the sweep VEP (sVEP). Results: The percentage of children outside the superior tolerance limits was 44 of 63 (69%) and 50 of 55 (91%) of tetraplegic, 36 of 56 (64%) and 42 of 53 (79%) of diplegic, 10 of 48 (21%) and 12 of 40 (30%) of hemiplegic for sVEP and TAC, respectively. For the sVEP, the greater visual acuity deficit found in the tetraplegic group was significantly different from that of the hemiplegic group (p < 0.001). In the TAC procedure the mean visual acuity deficits of the tetraplegic and diplegic groups were significantly different from that of hemiplegic group (p < 0.001). The differences between sVEP and TAC means of visual acuity difference were statistically significant for the tetraplegic (p < 0.001), diplegic (p < 0.001), and hemiplegic group (p = 0.004). Discussion: Better visual acuities were obtained in both procedures for hemiplegic children compared to diplegic or tetraplegic. Tetraplegic and diplegic children showed greater discrepancies between the TAC and sVEP results. Inter-ocular acuity difference was more frequent in sVEP measurements. Conclusions: Electrophysiologically measured visual acuity is better than behavioural visual acuity in children with CP.FAPESP [02/12733-8]CNPq [523303/95-5]USP-PROPESPCAPES/PROCAD [0019/01-1

A review of experimental task design in psychophysical eye tracking research

While eye tracking is a technique commonly used in the experimental study of higher-level perceptual processes such as visual search, working memory, reading, and scene exploration, its use for the quantification of basic visual functions (visual acuity, contrast sensitivity, color vision, motion detection) is less explored. The use of eye movement features as dependent variables in a psychophysical investigation can serve multiple roles. They can be central in studies with neurological patients or infants that cannot comply with verbal instructions, understand task demands, and/or emit manual responses. The technique may also serve a complementary role, determining the conditions under which a manual or verbal response is given, such as stimulus position in the visual field, or it can afford the analysis of new dependent variables, such as the time interval between oculomotor and manual responses. Our objective is to review the literature that applied the eye tracking technique to psychophysical problems. The two questions our review raises are: can eye movements (reflex or voluntary) be an objective index of stimulus detection in psychophysical tasks? If so, under what conditions, and how does it compare with traditional paradigms requiring manual responses? Our (non-systematic) methodological review selected studies that used video-oculography as the technique of choice and had a basic visual function as their primary object of investigation. Studies satisfying those criteria were then categorized into four broad classes reflecting their main research interest: (1) stimulus detection and threshold estimation, (2) the effects of stimulus properties on fixational eye movements, (3) the effects of eye movements on perception, and (4) visual field assessment. The reviewed studies support the idea that eye tracking is a valuable technique for the study of basic perceptual processes. We discuss methodological characteristics within each of the proposed classification area, with the objective of informing future task design

Avaliação visual de sujeitos expostos de forma ocupacional a solventes orgânicos através de métodos psicofísicos

Les solvants organiques sont des substances neurotoxiques que peuvent causer des effets préjudiciables dans le système visuel. Lexposition professionnelle de ces types de substances est commune parce quils sont utilisés dans une grande variété dactivités. Ces effets peuvent être quantifiés par des tests spécifiques de psychophysique. Les tests les plus utilisés dans cette évaluation sont, pour la vision des couleurs, le Lanthony Panel D-15 désaturé et le test Farnsworth-Munsell 100-Hue, et pour lévaluation de la sensibilité au contraste, le MCT 8000 Vistech, le VCTS 6500 Vistech et le FACT 101. Généralement, ces tests révèlent une réduction de discrimination des couleurs, des effets dans les axes bleu-jaune et rouge-vert, et une diminution de sensibilité au contraste, spécialement dans les basses fréquences spatiales. Il y a une corrélation positive entre les résultats psychophysiques et les marqueurs biologiques environnementaux, mais cette corrélation dépend du marqueur et du type de solvant auquel le sujet a été exposé. Des facteurs tels que lalcool et le tabac peut nuire à la corrélation des résultats.Los solventes orgánicos son sustancias neurotóxicas que pueden causar efectos dañinos en el sistema visual. La exposición ocupacional a estas sustancias es común, ya que se utilizan en una amplia variedad de actividades. Estos efectos pueden ser cuantificados por las pruebas psicofísicas específicas. Las pruebas más utilizadas para la evaluación de la visión del color son las pruebas de acuerdo, tales como el Panel de Lanthony D-15 desaturado de prueba y la prueba de Farnsworth-Munsell 100-hue, y para evaluar la sensibilidad al contraste, pruebas impresas panel como el MCT 8000 VISTECH, VCTS 6500VISTECH, y el hecho 101 pruebas. En general, estas pruebas demuestran que las pérdidas de color la discriminación en el eje azul-amarillo y rojo-verde, y una disminución de la sensibilidad al contraste, sobre todo a bajas frecuencias espaciales. Hay una correlación positiva entre los resultados de estudios biológicos y psicofísicos marcadores del medio ambiente, pero esta relación depende de la marca y del tipo de disolvente para que los individuos estén expuestos. Factores tales como el alcohol y el tabaco pueden interferir con la correlación de los resultados.Organic solvents are neurotoxic substances that can cause damaging effects in the visual system. Occupational exposure to these substances is common because they are used in a wide variety of activities. These effects can be quantified by specific psychophysical tests. The most commonly used tests for color vision assessment are arrangement tests, such as the Lanthony Panel D-15 desaturated test and the Farnsworth-Munsell 100-hue test, and for contrast sensitivity assessment, printed panel tests such as the MCT 8000 VISTECH, VCTS 6500VISTECH, and FACT 101 tests. Generally, these tests show color discrimination losses in the blue-yellow and red-green axis, and a decrease in contrast sensitivity, mainly at low spatial frequencies. There is a positive correlation between psychophysical results and biological environmental markers, but this correlation depends on the marker and on the kind of solvent to which the individuals are exposed. Factors such as alcohol and tobacco can interfere with the correlation of the results.Os solventes orgânicos são substâncias neurotóxicas que podem causar efeitos danosos sobre as funções visuais. É comum a exposição ocupacional a esses tipos de substâncias, pois elas apresentam grande aplicabilidade em inúmeras atividades. Os efeitos podem ser quantificados por testes psicofísicos. Os testes mais usados nesse tipo de avaliação são de ordenamento de matizes, como o Teste D15 Dessaturado de Lanthony e o Teste dos 100 Matizes de Farnsworth-Munsell, e avaliação de sensibilidade ao contraste espacial de luminância, como MCT 8000 Vistech, VCTS 6500 Vistech e FACT 101. Em geral esses testes descrevem perda de discriminação de cores, afetando tanto o eixo azul-amarelo quanto o eixo verde-vermelho, e diminuição da sensibilidade ao contraste de luminância principalmente para as frequências espaciais mais baixas. Existe correlação positiva entre os resultados da avaliação psicofísica e vários marcadores biológicos e ambientais, mas essa correlação depende do marcador e do tipo de solvente ao qual os indivíduos são expostos. Fatores como alcoolismo crônico e tabagismo inveterado podem interferir no processo de correlacionar esses resultados

Behavior profile and social competence in children and adolescents with Duchenne muscular dystrophy

A distrofia muscular de Duchenne é uma doença genética caracterizada por enfraquecimento muscular progressivo e degeneração irreversível, acompanhados por danos sensoriais e neuropsicológicos. Os objetivos do estudo consistiram em avaliar o perfil comportamental de crianças/adolescentes com DMD e a influência do prejuízo motor, da idade no início do uso de cadeira de rodas e da idade no diagnóstico. Participaram 34 pacientes e 20 controles. Os pacientes formaram dois grupos conforme o quociente de inteligência (QI). Os pais responderam ao Inventário de Comportamentos da Infância e da Adolescência. Pacientes com DMD obtiveram escores mais baixos em Atividades e Sociabilidade (p < 0,01; ANCOVA). Os pacientes com QI < 80 apresentaram menores índices de Escolaridade. O prejuízo motor e as idades referentes à cadeira e ao diagnóstico correlacionaram-se com sintomas psiquiátricos/somáticos e problemas escolares. Os achados enfatizam a necessidade de programas educacionais acerca da doença como base para o desenvolvimento de estratégias de inclusão social

Psychophysical Measurements of Luminance Contrast Sensitivity and Color Discrimination with Transparent and Blue-Light Filter Intraocular Lenses

The purpose of this study was to measure luminance contrast sensitivity and color vision thresholdfs in normal subjects using a blue light filter lens and transparent intraocular lens material. Monocular luminance grating contrast sensitivity was measured with Psycho for Windows (version 2.36; Cambridge Research Systems) at 3.0, 6.0, 12.0, 20.0, and 30.0 cycles per degree of visual angle (cpd) in 15 normal subjects (eight female), with a mean age of 21.6 years (SD = 3.8 years). Chromatic discrimination was assessed with the Cambridge colour test (CCT) along the protan, deutan, and tritan color confusion axes. Both tests were performed in a darkened room under two situations: with a transparent lens and with blue light filter lens. Subjective impressions were taken by subjects regarding their visual experience under both conditions. No difference was found between the luminance contrast sensitivity measured with transparent and blue light filter. However, 13/15 (87%) of the subjects reported more comfortable vision with the blue filter. In the color vision test, tritan thresholds were significantly higher for the blue filter compared with the transparent filter (p = 0.003). For protan and deutan thresholds no differences were found. Blue-yellow color vision is impaired with the blue light filter, and no impairment occurs with the transparent filter. No significant differences in thresholds were found in the luminance contrast sensitivity comparing the blue light and transparent filters. The impact of short wavelength light filtering on intrinsically photosensitive retinal ganglion cells is also discussed.FAPESP Projeto TematicoFINEPCNPqUniv Sao Paulo, Dept Psicol Expt, Inst Psicol, Sao Paulo, BrazilUniv Sao Paulo, Nucleo Neurociencias & Comportamento & Neurocienc, Sao Paulo, BrazilUniv Fed Sao Paulo, Dept Oftalmol, Sao Paulo, BrazilHosp Israelita Albert Einstein, Sao Paulo, BrazilUniv Fed Sao Paulo, Dept Oftalmol, Sao Paulo, BrazilFAPESP Projeto Tematico: 02/12733-8FINEP: 66.95.0407.00CNPq: 523303/95-5Web of Scienc