Identification of emotional expressiveness in facial photographs over 36†h of extended vigilance in healthy young men-a preliminary study.

Changes in sleep patterns negatively influence some emotional responses, but their effects on facial expressiveness identification are unclear. To investigate these effects, 21 young, healthy, male volunteers of intermediate chronotype evaluated emotional expressiveness of faces depicting 6 basic emotions in 5 emotional gradients every 4 h over 36 h of continuous wakefulness. To measure attention and mood we used the Psychomotor Vigilance test and the Positive and Negative Affect Schedule Expanded, respectively. We found effects of emotional gradient for all types of emotions (100% > 80% > 60% > 40% > 20%) during all tested periods, with no indications of circadian effects. The only emotional rating to be affected was disgust, which was progressively blunted throughout the experiment. This effect did not parallel homeostatic and circadian changes in mood, alertness or attention. We conclude that identifying disgust on facial photographs is particularly sensitive to lack of sleep irrespective of sleep-induced changes in mood and attention in males.

Executive functioning in obstructive sleep apnea syndrome patients without comorbidities: focus on the fractionation of executive functions.

PURPOSE: Obstructive sleep apnea syndrome (OSAS) is associated with impaired cognition, especially executive functions. However, various of its comorbid conditions are also known to cause cognitive impairment, so it is unclear whether OSAS itself is responsible for cognitive deficits. Our aim was to determine the effects of OSAS on executive functions in otherwise healthy patients. METHOD: This was a parallel group design study, which involved 22 patients aged 36-65 years diagnosed with moderate to severe OSAS, whose body mass index was below 26, and who did not have diabetes, hypertension, or depression. Controls were 22 healthy individuals with similar age, gender, intelligence quotient, and schooling to those of the patients. Participants completed a test battery that included measures of 6 distinct executive domains (shifting, inhibition, updating, dual-task performance, planning, and access to long-term memory), of all subsystems of the multiple-component working memory model, attention, and mood. RESULTS: OSAS and controls were equivalent in all demographic variables and test scores. The apnea-hypopnea index did not significantly correlate with executive performance, but mean oxygen saturation did so with measurements of executive shifting and access to long-term memory. CONCLUSIONS: OSAS without comorbidities did not lead to cognitive impairment.

Equipamento portátil para ensaios simultâneos de teste de vigilância psicomotora e pupilometria / Portable equipment for simultaneous assays of psychomotor vigilance test and pupillometry

Neste artigo é descrito um sistema com potencial para identificar a privação do sono, que, com base no levantamento bibliográfico realizado, ainda não foi abordado na literatura. Este sistema integra simultaneamente duas metodologias, o teste de vigilância psicomotora (Psychomotor vigilance test, PVT) e a pupilometria, que se destacam no estudo da privação do sono. Entretanto, para atender às peculiaridades destas metodologias, permitindo que coexistam em um único sistema, algumas adaptações foram realizadas em seus procedimentos. Esta integração poderá garantir não só a complementariedade de indicadores que torna a identificação da privação do sono mais robusta, assim como estabelecer a equalização do estado psicofisiológico do sujeito, o que não é possível em testes realizados com defasagem temporal. Neste estudo, a validação das métricas do sistema foi realizada com sujeitos em estado de alerta. Os resultados mostraram-se coerentes com a literatura. Entretanto, algumas métricas apresentam um deslocamento em seus valores médios, que segundo as avaliações realizadas são determinadas pelas exigências técnicas do sistema. Os resultados obtidos nesta avaliação, somados à crescente demanda de ferramentas de aplicação em larga escala e que possam ser utilizadas além dos limites laboratoriais para estudos em distúrbios e privação do sono, apontam este sistema como uma potencial ferramenta. Entretanto, será necessário o estabelecimento de um experimento rigoroso, para avaliar se os indicadores oriundos das métricas do sistema permitem a identificação robusta da privação do sono.

This paper describes a system with potential for identification of sleep deprivation, which, based on our bibliographical survey, has not yet been described in the literature. The system combines two methodologies, i. e., Psychomotor vigilance test (PVT) and pupillometry, which are among the leading methods for the study of sleep deprivation. However, due to peculiarities of both methodologies, some adaptations were made in their procedures to allow them to co-exist in the same system. Such integration may not only ensure the complementarity of indexes, making the identification of sleep deprivation more solid, but also set up the equalization of the subject's psycho-physiological state, which is not possible in tests performed with a time lag. In this study, the performance of measurements provided by the system was assessed in subjects on alert. However, some measurements present a displacement with respect to their average values, which, according to assessment, are determined by system's technical requirements. The results obtained in this assessment, combined with the increasing demand for large scale application tools, able to be used outside the limits of the laboratory environment for studies in sleep deprivation disorders, point to this system as a potential tool. However, the undertaking of a rigorous experiment is necessary to assess whether the indexes obtained by the system allow the robust identification of sleep deprivation.