To investigate factors that affect the mutual entrainment of vocal activity rhythms, female general psychology students paired according to attitude similarity questionnaires engaged in 40-minute introductory conversations. Fourier analyses performed on speakers' on-off vocal activity demonstrated periodic oscillations in talkativeness. Although some dyads coordinated their vocal activity rhyth...

Although schistosomiasis has been a public health issue in Gabon for nearly a century, little is known about its current transmission dynamics. We analyzed the chronobiology of 137 cercarial emission profiles of Schistosoma haematobium from Libreville, the capital of Gabon, located in an open area for schistosomiasis. We found that 88% of the cercariae were shed between 11 a.m. and 3 p.m. and t...

Sponsored by the CNPq (Processes ns. 132203/98-7 and 301596/79-4 – National Research Council Master and Researcher I Grants) and from the Association Fund of Incentive to Psychopharmacology (AFIP). Part of the Master thesis “Study on the Bioavailability and Chronobiology of Lithium in Healthy Volunteers”, presented to the Department of Psychobiology of the Unifesp/EPM, 2000. This study was part...

Although homeostatic mechanisms remain of utmost importance, rhythmic changes are present also. The main ones have a period of 24 h (circadian) or about 2-3 h (ultradian). Circadian rhythms are derived from a body clock, found in the base of the brain, and from the pattern of our sleep-wake cycle, including activity and meal times. These rhythms promote the regular changes between an active wak...

The complaint of excessive daytime sleepiness (EDS), commonly encountered in clinical practice, may arise from a variety of psychiatric disorders, most importantly depression. Even though EDS frequently leads depressed patients to seek medical assistance, it is commonly under-evaluated and under-diagnosed. Therefore, a comprehensive understanding and management of EDS is essential in the clinic...

Although much of the emphasis in treating Bipolar Disorder patients is on pharmacotherapy, sleep loss is an important trigger for mania and plays an important role in the condition. The purpose of this paper is to fully explore the chronobiological, environmental, social, and genetic factors that contribute to the sleep disruption that is characteristic of mania and bipolar disorder. This revie...

Recent advances in archaeology, chronobiology, and history of science have made it possible to decipher hitherto obscure passages related to planets in the Indian books of the third millennium BC. A brief summary of this knowledge is presented. It is argued that the period of Mercury was obtained near the end of the Vedic age in India. This was celebrated in terms of the famous myth of Vishnu s...

BACKGROUND Circadian variation may affect many biological and pharmacological phenomena. METHODS To assess circadian variations in labour pain perception, 222 consecutive nulliparous women with uncomplicated pregnancy, spontaneous labour, cervical dilatation (3-5 cm), ruptured membranes and normal fetal heart rate tracings were studied. Visual analogue pain scores (VAPS) were analysed and div...

Chronobiology, especially the study of circadian rhythms, provides a model scientific field in which philosophers can study how investigators from a variety of disciplines working at different levels of organization are each contributing to a multi-level account of the responsible mechanism. I focus on how the framework of mechanistic explanation integrates research designed to decompose the me...