Natanael Antonio dos Santos

• PhD
• Professor (Full) at Federal University of Paraíba

There are significant gaps in understanding the extent of the damage caused by COVID-19, with few publications examining its link to contrast sensitivity function (CSF). The aim of the present study was to evaluate CSF at low, medium, and high spatial frequencies in individuals with and without a history of COVID-19. Thirty adults, both male and fe...

Identificar os impactos da pandemia na saúde mental e física dos idosos. Trata-se de um estudo descritivo, exploratório de campo e abordagem qualitativa, realizado em duas Unidades Básicas de Saúde, localizadas no interior do Ceará. A coleta de dados foi realizada no mês de maio de 2022 de forma presencial, com a aplicação de uma entrevista semiest...

Objective The present study investigated attentional biases in anxiety using facial expressions and eye-tracking measures. Method Seventy-six participants, between 18 and 36 years, took part in the study and were divided based on trait anxiety levels: Low, Moderate, and High. The stimuli were facial expressions, and the measures of interest were Pr...

Parkinson’s disease is the second most common neurodegenerative disease, but therapeutic options such as neuromodulation continue to show variable effects, making clinical management of the disease difficult. This systematic review with meta-analysis and meta-regression aimed to analyze the isolated effect of cortical modulation with transcranial d...

Obsessive-compulsive disorder (OCD) is a debilitating neuropsychiatric disorder characterized by persistent obsessive and compulsive symptoms. Dysfunctions in two inhibitory systems related to cognitive and behavioral processes are believed to be associated with the pathophysiology of OCD. These dysfunctions can affect not only the cognitive and be...

Chemotherapy is one of the most widely used treatments for breast cancer (BC). However, there is evidence of side effects like cognitive changes related to the chemotherapy treatment. The aim of the study was not only to summarize the existing evidence on the relationship between chemotherapy and cognitive performance in women with BC but also to i...

Bipolar disorder (BPD) is a chronic condition characterized by recurrent episodes of mania and depression. To date, the association of biological and psychopathological processes in BPD has not been extensively studied on a cognitive and cortical basis at the same time. We investigated whether brain atrophy (in prefrontal, temporal and occipital co...

This study investigated the efects of antineoplastic treatment (chemotherapy and hormone therapy) on visual processing of women with breast cancer. A systematic review of the published studies on the subject was conducted in the databases PubMed, Web of Science, Cochrane Library, PsycINFO, CINAHL, EMBASE and Scopus from its inception until June 1,...

Esta cartilha é direcionada aos manipuladores de alimentos de serviços de alimentação, do tipo Buffet, no qual apresenta informações importantes para o planejamento de ações que proporcione e garanta a manipulação adequada de alimentos nesses estabelecimentos. Assim, a proposta prioriza os conhecimentos básicos que envolvem o fornecimento de alimen...

Schizophrenia (SCZ) can be described as a functional dysconnectivity syndrome that affects brain connectivity and circuitry. However, little is known about how sensory stimulation modulates network parameters in schizophrenia, such as their small-worldness (SW) during visual processing. To address this question, we applied graph theory algorithms t...

Objective: The process of detecting faces can be considered one of the initial steps in face recognition, which is essential for human interaction. We sought to investigate whether a face perception task reliably detects subtle perceptual disturbances between patients with bipolar disorder (BD) and healthy controls. Methods: In this multisite st...

The main purpose of this pilot study was to investigate the immediate effects of Automatic Self-Transcending (AST) meditation on the cognitive function, EEG activity and autonomic arousal (Study 1) and characterize the frontal EEG synchrony during resting state, cognitive activity and AST mental states in traditional and wireless EEG’s (Study 2). W...

Studies reported that previous experience or training with video games can lead to improvements on perceptual and sensory processing. However, the results are scarce and often contradictory. An explanation may be related to differences in procedures, training, types of games and samples used in the studies. Here, we investigate whether or not video...

Resumo Estudos mostram que o tabagismo é responsável por afetar algumas funções cognitivas. No entanto, a nicotina é apenas um dos componentes existentes no cigarro e existem evidências de que pode servir como agente neuroprotetivo e causar melhoras em algumas funções cognitivas. O objetivo desta pesquisa foi investigar como a nicotina interage com...

Chronic tobacco consumption, identified as Tobacco Use Disorder (TUD), is a public health problem. We present a case report of a 37-year-old Brazilian male diagnosed with TUD at age 26, with no comorbidities, that presented visual improvements (i.e., lower thresholds and better discrimination) after nicotine gum administration. Here, we assessed co...

Malnutrition is characterised by deficient nutrient ingestion and absorption and is still one of the most important causes of morbidity and mortality in children worldwide. Our main rationale was that protein‐energy malnutrition (PEM) may affect eye movement in children with malnutrition. Twenty children without PEM (mean age = 10.8; SD = 1.0 years...

The use of noninvasive tools can help understand mental states and changes that are caused by medications, symptom severity, and other clinical variables. We investigated low-level visual processing using the contrast sensitivity function (CSF), a reliable, robust, and widely used approach. Our main purpose was (1) to evaluate visual impairments in...

Bipolar (BPD) patients have deficits in cognition, but there are still controversies about the effects of some medications on their cognitive performance. Here, we investigated the relationship between cognition in terms of executive function, memory, and attention in both first-episode medication-naive BPD patients and BPD patients taking olanzapi...

Earlier studies have reported visual impairments in patients with bipolar disorder (BPD), but is not clear which clinical variables are associated with those disturbances. Here, we investigate the relationship between visual functioning, in terms of chromatic discrimination, and the impact of BPD duration, mood state, and the patients' medication....

Background: This article systematically updates the literature on changes in visual functions during the phases of the normal menstrual cycle in women. Objectives: To update Guttridge's 1994 review of visual structures and functions associated with the menstrual cycle and broaden the search through psychophysical, neuroimaging and neurobehaviora...

Objective: The main purpose of this study was to investigate the isolated effects of nicotine on visual processing, namely contrast processing. Methods: Thirteen participants, aged 18–40 years, were enrolled in this double blind, randomized and pilot controlled trial involving nicotine gum administration (placebo, 2-mg and 4-mg doses). The particip...

The use of serious games and entertainment games was compared as adjuvant tools for intervention in Autism Spectrum Disorder (ASD). A comprehensive search was performed in the MEDLINE, PsycINFO, Scopus, and Web of Science databases. From 295 studies, 53 studies were selected and included in this review. Overall, studies showed improvement after int...

This systematic review aimed to verify the empirical evidence of the application of the eye tracking technique in depressive disorder. The PubMed, PsyInfo and Web of Science databases were used, using the following descriptors: ((Depression OR "Affective Disorders") AND ("Eye Tracking" OR Eye-Tracking OR "Eye Movements" OR "Eye Tracker" OR "Eye Gaz...

Previous studies have shown that patients diagnosed with schizophrenia (SCZ) have deficits in early visual processing, namely contrast processing. The brain-derived neurotropic factor (BDNF) is an important measure to investigate neuroplasticity in some visual functions like visual perception. In this study, we investigated the relationship between...

Aging has been associated with the functional decline of episodic memory (EM). Unanswered questions are whether the decline of EM occurs even during healthy aging and whether this decline is related to amyloid-β (Aβ) deposition in the hippocampus. Objective: The main purpose of this study was to investigate data on the relationship between the ag...

Objectives: The effects of smoking on color vision have been scarcely studied. To bridge such gap, this study examined if there were differences in chromatic discrimination between heavy and light smokers. Methods: The psychophysical Trivector test was used to evaluate chromatic discrimination in healthy controls (n = 36), heavy smokers (n = 29),...

Schizophrenia can be described as a functional dysconnectivity syndrome that affects the brain’s circuits in a generalized way. Global disconnection in schizophrenia has been manifold described by applying graph theory and quantifying parameters of network connectivity. However, little is known about how sensory stimulation modulates networks in sc...

Background Although some studies have shown impairments in patients with bipolar disorder (BPD) and in smokers, it is unclear how these two factors work together. Our premise was that chronic smoking affects color discrimination and this is more pronounced in BPD. Objective: Our main purpose was to investigate the influence of smoking and BPD on co...

This systematic review aimed to verify the empirical evidence of the application of the eye tracking technique in depressive disorder. The PubMed, PsyInfo and Web of Science databases were used, using the following descriptors: ((Depression OR "Affective Disorders") AND ("Eye Tracking" OR Eye-Tracking OR "Eye Movements" OR "Eye Tracker" OR "Eye Gaz...

Obesity is a serious, chronic, and progressive disease associated with physiological dysfunctions that interact with circadian clock activity. Vertical gastrectomy (VG) is currently the most frequently performed bariatric procedure for the treatment of obesity. The objective of this case study was to verify the effect of VG on sleep quality, eating...

Obesity is a serious, chronic, and progressive disease associated with physiological dysfunctions that interact with circadian clock activity. Vertical gastrectomy (VG) is currently the most frequently performed bariatric procedure for the treatment of obesity. The objective of this case study was to verify the effect of VG on sleep quality, eating...

A Fibrose cística (FC) é uma doença rara que se manifesta ainda na infância ou na adolescência, é altamente letal e multissistêmica, gerada através da mutação no gene que codifica a Proteína Reguladora da Condutância Transmembrana da Fibrose Cística, o que provoca aumento da viscosidade do muco no corpo humano e necessita-se de formas de diagnóstic...

Introduction: Deafness can be considered as partial or total hearing loss that makes it impossible to receive or process sound stimuli, and cause changes in other sensory systems, such as the visual system. Objective: This study evaluated whether hearing deprivation alters the color perception discrimination of young adults and Brazilian Sign Langu...

Background: Malnutrition is characterized by impaired nutrient ingestion and absorption, and it is still one of the most substantial causes of morbidity and mortality in children worldwide. To the best of our knowledge, this is the first study investigating eye tracking in children with protein-energy malnutrition (PEM). We sought to investigate ho...

Literature indicates that long-term experience with action video games can lead to improvements in visual information processing in some tasks. However, few studies investigate the effects on contrast sensitivity. The present study aimed to investigate whether video game players (VGPs) and non-video game players (NVGPs) would perform differently in...

COVID-19 is a highly contagious respiratory disease caused by a virus with high neuroinvasive potential. Both structural and functional alterations in the eye have been identified in post-covid patients. However, there are still gaps regarding the implications on sensory processing. Our purpose was to investigate sensory and perceptual alterations...

A tipologia circadiana é uma dimensão comportamental associada a preferências de hábitos diários. Contudo, este estudo objetivou avaliar a qualidade de sono e a sonolência excessiva de acadêmicos de Psicologia. Participaram deste estudo quase-experimental 56 estudantes com idade entre 17 e 34 anos. Utilizaram-se como instrumentos o Índice de Qualid...

O objetivo desta pesquisa foi obter dados normativos de um conjunto de faces do Karolinska Directed Emotional Faces (KDEF) em uma amostra brasileira. Para isso foi utilizada uma amostra não probabilística (por conveniência) de 100 participantes da cidade de João Pessoa-PB. Esses tinham idades entre 18 e 62 anos (M=21,6; DP=6,2), a maioria do sexo f...

Abstract The aim of this study was to analyze the contrast sensitivity of spatial luminance and the color discrimination thresholds of the protan, deutan, and tritan axes of people with leprosy. This study included 8 subjects with leprosy (M = 4, W = 4, M = 33.38 ± 8.7) and 8 healthy subjects (M = 4, W = 4, M = 30.89 ± 5.8). The contrast sensitivit...

This study aimed to verify the daily variation in the chromatic visual sensitivity of healthy subjects. The study included 35 male adults, aged between 20 and 40 years old (M = 24.97; SD = 4.9). The evaluation of color perception was made through the Cambridge Colour Test, using the Trivector and Ellipse tests. The Pittsburgh Sleep Quality Index, t...

Resumo O objetivo desta pesquisa foi adaptar a Structured Interview for Assessing Perceptual Anomalies (SIAPA) para o Brasil para ser utilizada como instrumento de autorrelato. Utilizou-se uma amostra não probabilística de 854 universitários, a maioria do sexo masculino (51,4 %) e com idades entre 16 e 65 anos (M = 23,7; DP = 6,8). Após a tradução...

Objective: Chronic tobacco consumption, classified as tobacco use disorder (TUD), has been associated with a variety of health problems. Investigations of face processing in TUD are hampered by lack of evidence. Here, we evaluated facial detection in TUD and assessed test-retest reliability for a facial detection task. Methods: Participants were...

Os antibióticos estão sendo usados como tratamento experimental nos pacientes infectados com o coronavírus, em alguns pacientes houve uma melhora dos sinais e sintomas e uma redução da carga viral. A partir desses fatos, estudos estão sendo realizados para comprovar a eficácia dos antibióticos, especialmente dos macrolídios, devido a sua capacidade...

Primeiros socorros é definido pela prestação do suporte imediato com a finalidade de manutenção dos sinais vitais da vítima até a chegada da assistência especializada. Além dos profissionais de saúde, qualquer indivíduo com o conhecimento prévio do assunto pode realizar a prestação do socorro. Esta pesquisa objetivou conhecer a importância do conhe...

Studies reported that tobacco addiction was related to visual impairments, but one unresolved issue is whether the impairments are related to the many compounds existing in the cigarettes or to the effects of nicotine. On the other hand, nicotine gum can be used as replacement therapy or as a neuroprotective agent for some diseases. The main purpos...

Objective The main purpose of this study was to investigate short-term effects of nicotine gum on facial detection. Methods: Fourteen participants (mean age = 26.8 years, SD = 2.5 years; eight males) were enrolled in this pilot randomized controlled trial of nicotine gum administration (placebo, 2-mg and 4-mg doses). The participants were instructe...

Resumo: O objetivo desse estudo foi adaptar a Escala de Ansiedade de Falar em Público (PSAS) para o contexto brasileiro. Para isso contou-se com uma amostra por conveniência de 667 estudantes universitários com idades entre 18 e 60 anos (M = 24,17; DP = 5,43), a maioria mulheres (70,5%). Em relação a evidência de validade, por meio de Análises Fato...

Resumo: O objetivo desse estudo foi adaptar a Escala de Ansiedade de Falar em Público (PSAS) para o contexto brasileiro. Para isso contou-se com uma amostra por conveniência de 667 estudantes universitários com idades entre 18 e 60 anos (M = 24,17; DP = 5,43), a maioria mulheres (70,5%). Em relação a evidência de validade, por meio de Análises Fato...

Our main purpose was to investigate how smoking and nicotine interacted with specific aspects of cognitive functioning. The research was conducted in two parts: (i) an investigation of cognition in heavy smokers and healthy nonsmokers, and (ii) an investigation of cognition in healthy nonsmokers enrolled in a clinical trial involving administration...

Com o objetivo de analisar a equipe de enfermagem quanto ao gerenciamento e procedimentos realizados para promoção da segurança paciente. Trata-se de uma Revisão Integrativa da Literatura com abordagem qualitativa, onde a busca dos artigos se deu pelas seguintes bases de dados: SciELO; LILACS e MEDLINE, utilizando-se os descritores: Gerenciamento;...

This study evaluated reproducibility of the Trivector subtest of the Cambridge Colour Test. Data for normal trichromats were obtained in Brazil ( $ N = 111 $ ) at T0, six months (T1), and 12 months later (T2), and in the United Kingdom ( ${ N}={79}$ ), with the test directly followed by a retest. Coefficients of repeatability—Bland–Altman indices—f...

This study evaluated the neurocognitive aspects and eye-tracking of a control group (CG) consisting of 38 men (aged 31 ± 1.54 years) and a study group (SG) consisting of 38 male gas station workers (with 6.82 ± 5.62 years of service). Trail Making Tests A and B (TMT-A and -B), the Rey Complex Figure Test (RCFT), eye-tracking using a 250-Hz eye trac...

RESUMO Investigou-se a relação entre percepção visual e tremor essencial (TE). Realizou-se uma revisão dos estudos publicados sobre o tema nas bases de dados PubMed, BIREME, CINAHL, Web of Science, PsycINFO, SciELO, SCOPUS e ELSEVIER desde a origem até 05 de janeiro de 2017. A triagem, extração de dados e avaliação foram realizadas por dois revisor...

This study evaluated visual sensitivity to luminance contrast during a daily period. Twenty-eight young male adults (M = 24.85; SD = 2.4) with normal color vision and 20/20 visual acuity participated in this study. The circadian pattern was assessed using the Karolinska Sleepiness Scale (KSS), the Pittsburgh Sleep Quality Index (PSQI), and a sleep...

The objective of this study was to investigate whether there is a relationship between pupil diameter and facial attractiveness. Participated in the study 60 young adults (30 men and 30 women) between 18 and 26 years of age (M = 20.65, SD = 2.20). Ten different unfamiliar neutral faces (five men and five women) were used as stimuli. The pupil diame...

Objective: Patients with schizophrenia have visual processing impairments. The main findings from the literature indicate that these deficits may be related to differences in paradigms, medications, and illness duration. This study is part of a large-scale study investigating visual sensitivity in schizophrenia. Here we aimed to investigate the co...

Objectives: The present study evaluated early visual processing, in terms of the contrast sensitivity function (CSF), in bipolar disorder (BPD) patients. Methods: Data were recorded in 17 healthy participants and 17 outpatients with type 1 BPD, from 20 to 45 years of age. The CSF was measured at spatial frequencies of .2, .6, 3.1, 8.0, 16.0, and...

Purpose: The goals of the study were to further assess contrast sensitivity to (1) investigate the existence of monocular vs. binocular differences; (2) observe possible differences between sample sizes; (3) investigate the effects of test-retest repeatability. Methods: Contrast sensitivity measurements were obtained by presenting eight horizont...

Schizophrenia (SCZ) patients show deficits in many domains, including cognition and perception. However, results are often mixed. One reason for mixed results may be differences in medication. Very little is known about the role of medication in visual processing. Here, we investigated the effects of typical vs. atypical medication on contrast sens...

It was investigate the effect of organic solvents on the neurocognitive performance of men and women with and without chronic exposure to organic solvents and verify correlations between neurocognitive performance and body composition indices. Participants included 14 men and 14 exposed women and 14 men and 14 unexposed women. The Trail Making Test...

It was investigate the effect of organic solvents on the neurocognitive performance of men and women with and without chronic exposure to organic solvents and verify correlations between neurocognitive performance and body composition indices. Participants included 14 men and 14 exposed women and 14 men and 14 unexposed women. The Trail Making Test...

Prior studies found small effects of chronic smoking on spatial and color vision, but they were inconclusive. This study tries to: (1) replicate and extend these previous findings, and (2) rule in that this relationship is pronounced by tobacco addiction. Data were recorded in 71 healthy controls (M = 33.5 years; SD = 5.4 years) and 63 individuals...

Several studies have investigated cognition in bipolar disorder (BPD), but there is a large gap in the literature with regard to visual processing in BPD. The contrast sensitivity function (CSF) is one of the main measures that is used to verify and describe spatial processing responses and their mechanisms. The present article describes a retrospe...

The aim of the present study was to investigate the ways in which tobacco addiction affects a person’s ability to recognize facial patterns. Facial detection was assessed in 16 individuals with tobacco use disorder and 16 healthy nonsmokers. Facial stimuli were taken from the Ignatian Educational Foundation (FEI) database, from which 12 male and 12...

This study, an extension of Fernandes et al. (2017), provided consistent contrast sensitivity function (CSF) measurements in a large sample. CSF was assessed for luminance stimuli in different 48 chronic smokers and 50 healthy nonsmokers. Stimuli for the CSF were Gabor patches with spatial frequencies of .2, 2.5, 5.0, 10.0, and 20.0 cycles per degr...

Schizophrenia patients (SCZ) demonstrate deficits in many domains of mental functioning, including visual perception. An issue that has been relatively unexplored, in terms of explaining variation in visual function in SCZ, however, is medication use. The present study explored potential medication effects on color vision in SCZ, a process that is...

This study aimed to measure the axes of colors confusion according to the circadian typology (CT). For this purpose, 28 young male adults aged 20 to 28 participated in this study. The characteristics of the sample were: morning moderately (MM; n = 8; M = 23.25 ± 2.6); Intermediate (I; n = 10; M = 23.30 ± 2.7) and evening moderately (EM; n = 10; M =...

This study aimed to investigate the behavioral effects of sleep on the personality traits of young adults. The sample consisted of 114 volunteers with ages between 18 and 40. The subjects were characterized into three groups according to Horne and Östberg (1975): Moderately Morning (n = 23); intermediary (n = 52) and Moderately Evening (n = 39). Th...

This study analyzed the fluctuation of the achromatic visual contrast sensitivity (CS) of adult males (M = 23.42 ± 2.6 years) during a daily period. Twenty-eight volunteers were divided into three groups according to circadian typology (CT): moderate morning (MM; n = 8); intermediate (I; n = 10) and moderate evening (ME; n = 10). The Pittsburgh Sle...

Smoking prevalence in patients who are diagnosed with schizophrenia (SCZ) is higher than in the general population. Chronic tobacco use in SCZ patients may reduce the side effects of antipsychotic drugs, thus serving as a self-medication for such side effects. Understanding the ways in which chronic tobacco use influences visual sensitivity has cli...

This study aimed to investigate the behavioral effects of sleep on the personality traits of young adults. The sample consisted of 114 volunteers with ages between 18 and 40. The subjects were characterized into three groups according to Horne and Östberg (1975): Moderately Morning (n = 23); intermediary (n = 52) and Moderately Evening (n = 39). Th...

A 28-year-old White Brazilian female diagnosed with attention-deficit hyperactivity disorder began to experience severe headaches with photosensitivity. After misdiagnosis and inconclusive tests, the exams indicated the presence of idiopathic epilepsy secondary to migraine with aura. Because of the photosensitivity presented during the seizures, ou...

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, hu...

Research about the relationship between the acute alcohol ingestion and visual and auditory changes features applicability in issues related to everyday activities, such as orientation and mobility in transit and may favor the investigations about the influence of alcohol in the central nervous system (CNS) and on visual perception. However, even t...

Cigarette smoke is a complex chemical mixture, involving health-damaging components such as carbon monoxide, ammonia, pyridine, toluene and nicotine. While cognitive functions have been well documented in heavy smokers, spatial vision has been less characterized. In the article, we investigated smoking effects through contrast sensitivity function...

Organic solvents can change CNS sensory and motor function. Eye-movement analyses can be important tools when investigating the neurotoxic changes that result from chronic organic solvent exposure. The current research measured the eye-movement patterns of men and women with and without histories of chronic organic solvent exposure. A total of 44 v...

Although some studies have reported perceptual changes in psychosis, no definitive conclusions have been drawn about visual disturbances that are related to bipolar disorder (BPD). The purpose of the present study was to evaluate colour vision in BPD patients. Data were recorded from 24 participants: healthy control group (n = 12) and type 1 BPD gr...

Alcohol is one of the most consumed psychoactive substances in the world, and the negative impact related to alcohol use has become a worldwide public health issue. Alcohol is able to affect diffusely several areas of the Central Nervous System, which could impair visual functions, including eye movements, and cognitive processes. The objective of...

Data of blood alcohol concentration (BAC) levels for alcohol and placebo conditions. (XLSX)