SORRISO EM BEBÊS: REAÇÃO À FACE HUMANA E A VÁRIOS TIPOS DE DEGRADAÇÕES DESTE ESTÍMULO

face humana é um objeto privilegiado de percepção visual desde muito cedo no desenvolvimento.O objetivo do nosso trabalho foi investigar as alterações que ocorrem na reação a este objeto especial, aolongo do desenvolvimento inicial. Comparou-se a reação de bebês de quatro (n = 6), seis (n = 10) e novemeses (n = 11) aos seguintes tipos de estímulos: (a) rosto inteiro em posição frontal; (b) metade inferior dorosto, estando a superior tampada; (c) metade superior do rosto, estando a inferior tampada; (d) máscara deplástico, aderente à pele, com feições monstruosas. Cada estímulo era apresentado durante 60 segundos,registrando-se o tempo de sorriso e a ocorrência ou não de choro. Os bebês de nove meses sorriram durantemenos tempo (md = 2 seg) que aqueles de quatro (md = 9 seg) ao rosto todo (teste de Mann-Whitney,U = 16,0, p < 0,05), não havendo diferença entre os de seis e de nove meses. Na faixa etária menor, o rostointeiro desencadeou mais sorriso que a parte inferior do rosto (teste de Wilcoxon, T = 0,0, p < 0,05), nãohavendo diferença nas respostas ao rosto inteiro e à parte superior do rosto apenas (T = 24,0, p > 0,05). Esteresultado está de acordo com a conclusão de Spitz (1965) de que o sorriso em bebês pequenas é desencadeadopor um sinal gestáltico, que consiste numa parte circunscrita da face. Ele não reconheceria de fato oparceiro humano, mas apenas perceberia o sinal gestáltico da testa, olhos e nariz. Curiosamente, no entanto,não se encontrou diferença significativa no tempo de sorriso dos bebês de quatro e de nove meses emresposta à face de monstro

Amerindian (but not African or European) ancestry is significantly associated with diurnal preference within an admixed Brazilian population

Significant questions remain unanswered regarding the genetic versus environmental contributions to racial/ethnic differences in sleep and circadian rhythms. We addressed this question by investigating the association between diurnal preference, using the morningness–eveningness questionnaire (MEQ), and genetic ancestry within the Baependi Heart Study cohort, a highly admixed Brazilian population based in a rural town. Analysis was performed using measures of ancestry, using the Admixture program, and MEQ from 1,453 individuals. We found an association between the degree of Amerindian (but not European of African) ancestry and morningness, equating to 0.16 units for each additional percent of Amerindian ancestry, after adjustment for age, sex, education, and residential zone. To our knowledge, this is the first published report identifying an association between genetic ancestry and MEQ, and above all, the first one based on ancestral contributions within individuals living in the same community. This previously unknown ancestral dimension of diurnal preference suggests a stratification between racial/ethnic groups in an as yet unknown number of genetic polymorphisms

TNF and IL-6 levels in narcoleptic patients

Objective: To evaluate the presence of HLA-DQB1*0602 allele, tumornecrosis factor and interleukin-6 in patients with cataplexy andcontrols. Methods: A prospective controlled study with 22 patientsdiagnosed as narcoleptic according to DSM4 criteria and 17 healthycontrol subjects with no sleep disorders. All patients underwent anight-polysomnographic recording and HLA-DQB1*0602 study. Tumornecrosis factor and interleukin-6 levels of controls and patients werequantified. Results: The presence of HLA DQB1*0602 allele was foundin 10 patients with cataplexy and in 2 patients with no cataplexy (p =0.24). A significant increase in tumor necrosis factor in patients withrare cataplexy was observed when compared with controls (p =0.009), as well as a significant decrease in patients with rare cataplexyversus patients with frequent cataplexy (p < 0.0001). There were nodifferences in interleukin-6 levels between the groups. Conclusion:Discrepancies in clinical picture of narcoleptic patients may beassociated with subtle changes in the pathophysiological mechanismof the disease. The present study findings reinforce the hypothesis ofa probable immunological etiology for narcolepsy