Givago da Silva Souza

Universidade Federal do Pará

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i-10 index

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Document Type

Co-Authors

Luiz Carlos L. Silveira

Universidade Federal do Pará

101

Bruno Gomès

Universidade Federal do Pará

Bianca Callegari

Universidade Federal do Pará

Dora Fix Ventura

Universidade de São Paulo

Eliza Maria da Costa Brito Lacerda

Universidade Federal do Oeste do Pará

Anselmo de Athayde Costa e Silva

Universidade Federal do Pará

Letícia Miquilini

Universidade Federal do Pará

Alexandre Antônio Marques Rosa

Universidade Federal do Pará

Malinda E.C. Fitzgerald

University of Tennessee Health Science Center

Maria da Conceição Nascimento Pinheiro

Universidade Federal do Pará

Cooperative Institutions

Universidade Federal do Pará

285

Universidade do Estado do Pará

105

Universidade de São Paulo

Universidade Federal de São Paulo

Universidade Federal do Amapá

Centro Universitário do Maranhão

Universidade da Amazônia

Universidade Federal do Maranhão

Amazon Research Foundation

Universidade Estadual de Campinas (UNICAMP)

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Papers

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The Role of Art Expertise and Symmetry on Facial Aesthetic Preferences

Symmetry (2022)

Luis Carlos Pereira Monteiro Victória Elmira Ferreira do Nascimento Amanda Carvalho da Silva Ana Catarina Miranda Givago da Silva Souza

Humans, like other species, have a preference for symmetrical visual stimuli, a preference that is influenced by factors such as age, sex, and artistic training. In particular, artistic training seems to decrease the rejection of asymmetry in abstract stimuli. However, it is not known whether the same trend would be observed in relation to concrete stimuli such as human faces. In this article, we investigated the role of expertise in visual arts, music, and dance, in the perceived beauty and attractiveness of human faces with different asymmetries. With this objective, the beauty and attractiveness of 100 photographs of faces with different degrees of asymmetry were evaluated by 116 participants with different levels of art expertise. Expertise in visual arts and dance was associated with the extent to which facial asymmetry influenced the beauty ratings assigned to the faces. The greater the art expertise in visual arts and dance, the more indifferent to facial asymmetry the participant was to evaluate beauty. The same effect was not found for music and neither for attractiveness ratings. These findings are important to help understand how face aesthetic evaluation is modified by artistic training and the difference between beauty and attractiveness evaluations.

Beauty

Facial symmetry

Facial attractiveness

Fluctuating asymmetry

10.3390/sym14020423

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Citations (11)

Color vision impairment with low-level methylmercury exposure of an Amazonian population – Brazil

NeuroToxicology (2018)

Cláudia Feitosa-Santana Givago da Silva Souza Esaú Ventura Pupo Sirius Anderson Raiol Rodrigues Maria Izabel Tentes Côrtes

Land exploitation that follows deforestation and mining can result in soil erosion and the release of mercury to the waters of rivers in the Amazon Basin. Inorganic mercury is methylated by bacteria that are present in the environment and it serves as a source of human contamination through fish consumption in the form of methylmercury. Long-term exposure to low-level methylmercury in the riverside populations can lead to nervous system alterations, some of which are visual impairments such as loss of luminance contrast sensitivity, restricted visual fields and color vision defects. The present study sought to examine color vision in a group of adults living in the central Brazilian Amazon who were exposed to low-levels of methylmercury. Total Hg concentrations were measured from hair collected at the time of the testing. The D15d and FM100 color vision arrangement tests were applied in a population of 36 (22 males) and 42 (25 males), respectively. Controls were healthy volunteers from the cities of São Paulo for the D15d and Belém for the FM100. There was a statistically significant difference in performance between those who were exposed and controls for both tests (p < 0.01 and p < 0.0001, respectively, Mann-Whitney U test), meaning that adults living in this region of the Amazon made more mistakes on both tests when compared to controls. A linear regression was performed using Hg concentrations and test scores. Hg concentrations accounted for 7% and 2% of color D15d and FM100 arrangement test errors, respectively. Although other studies have previously found color vision impairment in the Amazon, they tested inhabitants on the east side of the Amazon, while this study was conducted in the central Amazon region and it is the first study in a population with no direct contact with the Hg source of contamination. These results suggest that long-term exposure to low-level methylmercury in riverside populations is more widely spread in the Amazon Basin than previously reported. This information is needed to implement public health policies that will ensure a safer environment for the Amazonian population.

Methylmercury

Amazon basin

Mercury

Color Vision Defects

10.1016/j.neuro.2018.01.010

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Citations (16)

VARIEGATED MOSAIC STIMULUS COMBINING LUMINANCE AND COLOR CONTRASTS FOR VISUAL EVALUATION

Anales/Anales AFA (2018)

Givago da Silva Souza Letícia Miquilini Florencia Brito Anderson Manoel Herculano Eliza Maria da Costa Brito Lacerda

La información de color y luminancia son atributos visuales importantes para detectar e identificar objetos en susentornos. El presente artículo revisa cómo se tiene investigado con estímulos de mosaico moteado para laevaluación del proceso de color y luminancia y cómo podrían ser un modelo de imágenes naturales.

Mosaic

10.31527/analesafa.2018.invisiont.7

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Citations (0)

Effect analysis of environmental factors on the children’s Amazon community neuropsychomotor development

Journal of Human Growth and Development (2018)

Ana Paula Pureza Pantoja Givago da Silva Souza Érica Feio Carneiro Nunes Lucieny da Silva Pontes

Introduction: The early years of a child’s life are marked by a significant development, as well as high sensitivity to environmental influences such as poverty, housing, quality and family structure. Thus, the identification of environmental risk factors and delayed neurodevelopment, coupled with early intervention, are essential for an healthy development. Objective: To analyze the effect of environmental factors on the neuropsychomotor development of children in the Amazon community. Methods: This is a quantitative and qualitative study of analytical and cross-sectional approach with 50 children between 24 and 36 months of age, of both sexes, living in an Amazonian community. Two types of the socio-economic-environmental questionnaire were used; a) Infant/Toddler (IT) HOME Inventory to analyze the quality of the family environment; b) the Denver Screening Test II for screening neurodevelopment. Also, a descriptive analysis was performed using a calculation of means and standard deviations. Results: The study found that a significant majority of the children had normal neuropsychomotor development; however, children classified as delayed, the more significant impact variable in the development was the quality of the family environment, which in turn was influenced by the lower economic class, lack of water treatment, lack of electricity and external toilet. Conclusion: Environmental factors were not significant on the neuropsychomotor development of the local children of the Amazon community.

Toddler

Environmental Quality

10.7322/jhgd.152158

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Citations (4)

Uniform trichromacy in Alouatta caraya and Alouatta seniculus: behavioural and genetic colour vision evaluation

Frontiers in Zoology (2021)

Leonardo Dutra Henriques Einat Hauzman Daniela Maria Oliveira Bonci Belinda S. W. Chang José Augusto Pereira Carneiro Muniz

Abstract Primate colour vision depends on a matrix of photoreceptors, a neuronal post receptoral structure and a combination of genes that culminate in different sensitivity through the visual spectrum. Along with a common cone opsin gene for short wavelengths ( sws1 ), Neotropical primates (Platyrrhini) have only one cone opsin gene for medium-long wavelengths ( mws/lws ) per X chromosome while Paleotropical primates (Catarrhini), including humans, have two active genes. Therefore, while female platyrrhines may be trichromats, males are always dichromats. The genus Alouatta is inferred to be an exception to this rule, as electrophysiological, behavioural and molecular analyses indicated a potential for male trichromacy in this genus. However, it is very important to ascertain by a combination of genetic and behavioural analyses whether this potential translates in terms of colour discrimination capability. We evaluated two howler monkeys ( Alouatta spp.), one male A. caraya and one female A. seniculus , using a combination of genetic analysis of the opsin gene sequences and a behavioral colour discrimination test not previously used in this genus. Both individuals completed the behavioural test with performances typical of trichromatic colour vision and the genetic analysis of the sws1 , mws , and lws opsin genes revealed three different opsin sequences in both subjects. These results are consistent with uniform trichromacy in both male and female, with presumed spectral sensitivity peaks similar to Catarrhini, at ~ 430 nm, 532 nm, and 563 nm for S-, M- and L-cones, respectively.

Trichromacy

Opsin

Color Vision Defects

10.1186/s12983-021-00421-0

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Citations (6)

Color Discrimination Is Affected by Modulation of Luminance Noise in Pseudoisochromatic Stimuli

Frontiers in Psychology (2016)

Iñaki Cormenzana Méndez Andrés Martín Teaire L. Charmichael Mellina Monteiro Jacob Eliza Maria da Costa Brito Lacerda

Pseudoisochromatic stimuli have been widely used to evaluate colour discrimination and to identify colour vision deficits. Luminance noise is one of the stimulus parameters used to ensure that subject's response is due to their ability to discriminate target stimulus from the background based solely on the hue between the colours that compose such stimuli. We studied the influence of contrast modulation of the stimulus luminance noise on threshold and reaction time colour discrimination. We evaluated colour discrimination thresholds using the Cambridge Colour Test (CCT) at six different stimulus mean luminances. Each mean luminance condition was tested using two protocols: constant absolute difference between maximum and minimum luminance of the luminance noise (constant delta protocol, CDP), and constant contrast modulation of the luminance noise (constant contrast protocol, CCP). MacAdam ellipses were fitted to the colour discrimination thresholds in the CIE 1976 colour space to quantify the colour discrimination ellipses at threshold level. The same CDP and CCP protocols were applied in the experiment measuring RTs at three levels of stimulus mean luminance. The colour threshold measurements show that for the CDP, ellipse areas decreased as a function of the mean luminance and they were significantly larger at the two lowest mean luminances, 10 cd/m2 and 13 cd/m2, compared to the highest one, 25 cd/m2. For the CCP, the ellipses areas also decreased as a function of the mean luminance, but there was no significant difference between ellipses areas estimated at six stimulus mean luminances. The exponent of the decrease of ellipse areas as a function of stimulus mean luminance was steeper in the CDP than CCP. Further, reaction time increased linearly with the reciprocal of the length of the chromatic vectors varying along the four chromatic half-axes. It decreased as a function of stimulus mean luminance in the CDP but not in the CCP. The findings indicated that visual performance using pseudoisochromatic stimuli was dependent on the Weber's contrast of the luminance noise. Low Weber's contrast in the luminance noise is suggested to have a reduced effect on chromatic information and, hence, facilitate desegregation of the hue-defined target from the background.

Stimulus (psychology)

Ellipse

Second-order stimulus

Hue

10.3389/fpsyg.2016.01006

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Citations (9)

Visual Evoked Cortical Potential (VECP) Elicited by Sinusoidal Gratings Controlled by Pseudo-Random Stimulation

PLoS ONE (2013)

Carolina S. Araújo Givago da Silva Souza Bruno Gomès Luiz Carlos L. Silveira

The contributions of contrast detection mechanisms to the visual cortical evoked potential (VECP) have been investigated studying the contrast-response and spatial frequency-response functions. Previously, the use of m-sequences for stimulus control has been almost restricted to multifocal electrophysiology stimulation and, in some aspects, it substantially differs from conventional VECPs. Single stimulation with spatial contrast temporally controlled by m-sequences has not been extensively tested or compared to multifocal techniques. Our purpose was to evaluate the influence of spatial frequency and contrast of sinusoidal gratings on the VECP elicited by pseudo-random stimulation. Nine normal subjects were stimulated by achromatic sinusoidal gratings driven by pseudo random binary m-sequence at seven spatial frequencies (0.4-10 cpd) and three stimulus sizes (4°, 8°, and 16° of visual angle). At 8° subtence, six contrast levels were used (3.12-99%). The first order kernel (K1) did not provide a consistent measurable signal across spatial frequencies and contrasts that were tested-signal was very small or absent-while the second order kernel first (K2.1) and second (K2.2) slices exhibited reliable responses for the stimulus range. The main differences between results obtained with the K2.1 and K2.2 were in the contrast gain as measured in the amplitude versus contrast and amplitude versus spatial frequency functions. The results indicated that K2.1 was dominated by M-pathway, but for some stimulus condition some P-pathway contribution could be found, while the second slice reflected the P-pathway contribution. The present work extended previous findings of the visual pathways contribution to VECP elicited by pseudorandom stimulation for a wider range of spatial frequencies.

Spatial frequency

Stimulus (psychology)

Achromatic lens

Photic Stimulation

Evoked potential

10.1371/journal.pone.0070207

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Citations (5)

Division of labor between M and P visual pathways: Different visual pathways minimize joint entropy differently.

Psychology & Neuroscience (2008)

Luiz Carlos L. Silveira Cézar Akiyoshi Saito Harold Dias de Mello Vladímir de Aquino Silveira Givago da Silva Souza

Visual perception and action are strongly linked with parallel processing channels connecting the retina, the lateral geniculate nucleus, and the input layers of the primary visual cortex. Achromatic vision is provided by at least two of such channels formed by the M and P neurons. These cell pathways are similarly organized in primates having different lifestyles, including species that are diurnal, nocturnal, and which exhibit a variety of color vision phenotypes. We describe the M and P cell properties by 3D Gabor functions and their 3D Fourier transform. The M and P cells occupy different loci in the Gabor information diagram or Fourier Space. This separation allows the M and P pathways to transmit visual signals with distinct 6D joint entropy for space, spatial frequency, time, and temporal frequency. By combining the M and P impacts on the cortical neurons beyond V1 input layers, the cortical pathways are able to process aspects of visual stimuli with a better precision than it would be possible using the M or P pathway alone. This performance fulfils the requirements of different behavioral tasks. Keywords: vision, M and P pathways, visual parallel processing, fourier space, joint entropy, information theory.

Parvocellular cell

Lateral geniculate nucleus

Achromatic lens

Visual space

Visual processing

Spatial frequency

10.3922/j.psns.2008.1.002

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Citations (2)

Análise Situacional das Hortas Comunitárias do Município de Palmas, Tocantins, Brasil: Uma Visão Etnofarmacológica

Revista Cereus (2015)

L.H.A. Gratão Giuliana Rondelli P.V.S. Silva Givago da Silva Souza E. Schott

A crescente procura por metodos terapeuticos alternativos e alimentacao saudavel, fez com que se desenvolvessem no pais projetos de farmacias vivas e hortas comunitarias, assim como Politicas Nacionais que regularizam o uso de Plantas Medicinais e Fitoterapicos pela populacao e profissionais da saude. Desse modo, o objetivo deste trabalho foi realizar levantamento situacional das hortas comunitarias do municipio de Palmas-TO, assim como verificar as condicoes de manejo e cultivo de hortalicas e plantas medicinais. Foi realizado uma pesquisa com 38 beneficiarios das hortas com o auxilio de um questionario semi-estruturado e observacao da estrutura fisica das hortas, tecnicas e ferramentas de manejo. Os dados agrupados e analisados com auxilio dos programas Microsoft Office Excel e Graph Pad Prism , sendo realizada analise descritiva dos mesmos. Verificou-se que 60% das hortas nao possuiam rede de esgoto; 97% faziam uso de defensores agricolas; mais de 40% utilizavam adubo de origem bovina; e apenas 3,8% dos produtos cultivados sao destinados para consumo proprio dos beneficiarios. Foi observado que apesar do objetivo do projeto das Hortas Comunitarias ter sido alcancado em parte, falta apoio e orientacao aos beneficiarios pelos profissionais da saude alem de apoio governamental, a fim de promover melhor qualidade na alimentacao e disponibilizar uma terapeutica alternativa mais acessivel atraves das plantas medicinais.

10.18605/2175-7275/cereus.v7n2p22-42

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Citations (1)

Visual psychophysics of congenital ocular toxoplasmosis case

Revista Brasileira de Oftalmologia (2018)

Raissa Cerveira Vieira Mirian Débora Rodrigues de Sousa Filipe Mycael Campos Silva Cândida Helena Lopes Alves Mauro César de Oliveira

Congenital ocular toxoplasmosis is a manifestation of infection by the parasite Toxoplasma gondii that occurs through the placenta. This disease can lead to important visual sequelae. This paper describes a case report that uses visual psychophysics for the alterations of congenital ocular toxoplasmosis. The evaluation was performed in a 30-year-old man, a resident of São Luís (MA), with a history of his mother have had toxoplasmosis in the gestational period. Only at 26 years-old he did the detailed medical evaluation [...]

Toxoplasmosis

Congenital toxoplasmosis

10.5935/0034-7280.20180064

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Citations (2)