Cycling reduces the entropy of neuronal activity in the human adult cortex.

Brain Complexity (BC) have successfully been applied to study the brain electroencephalographic signal (EEG) in health and disease. In this study, we employed recurrence entropy to quantify BC associated with the neurophysiology of movement by comparing BC in both resting state and cycling movement. We measured EEG in 24 healthy adults and placed the electrodes on occipital, parietal, temporal and frontal sites on both the right and left sides of the brain.

Association of Meal Timing with Sleep Quality and Anxiety According to Chronotype: A Study of University Students.

There are several determinants of mental health symptoms, ranging from individual characteristics to social factors. Consistent with patterns in the general population, students with evening characteristics tend to exhibit more anxiety symptoms and poorer sleep quality compared to morning students. Meal timing also appears to affect sleep and may be associated with mental health symptoms.

Changes in the rest-activity rhythm in migraine patients are associated with anxiety symptoms.

Objective: To characterize rest-activity rhythm in chronic migraine (CM) and to investigate the relationship between this rhythm and depressive and anxiety symptoms in patients with CM.

Methods: This was a study of adults aged 20 to 40 years. The rest-activity rhythm of patients with CM (n=23) and non-headache controls (NH, n=23) was assessed by actigraphy for 15 days, and they completed the following assessments: Visual Analogue Scale for pain intensity; Headache Diary; Headache Impact Test-6; Morningness-Eveningness Questionnaire; Pittsburgh Sleep Quality Index; Epworth Sleepiness Scale; Beck Depression Inventory; and State-Trait Anxiety Inventory.

Different sleep patterns during the COVID-19 pandemic: association with mood, exercise and light exposure.

The aim was to evaluate the sleep-wake cycle pattern, mood, perceived stress and some behaviors, such as physical exercise and exposure to natural light of college students during the COVID-19 pandemic. This is a cross-sectional study conducted between June and August 2020 using an electronic form provided by Google. The sample consisted of undergraduate students aged between 18 and 30 years old and residents of the northeast region of Brazil.

Predictors of stress in college students during the COVID-19 pandemic.

Background: College students experience high stress levels during emergency remote classes in the COVID-19 pandemic. However, it is not clear whether this is due to the summation effect of both stressors (classes and pandemic). Therefore, the aim of this study was to investigate predictors of stress in college students before and during remote classes five months after the beginning of the COVID-19 pandemic.

Structural differences between REM and non-REM dream reports assessed by graph analysis.

Dream reports collected after rapid eye movement sleep (REM) awakenings are, on average, longer, more vivid, bizarre, emotional and story-like compared to those collected after non-REM. However, a comparison of the word-to-word structural organization of dream reports is lacking, and traditional measures that distinguish REM and non-REM dreaming may be confounded by report length. This problem is amenable to the analysis of dream reports as non-semantic directed word graphs, which provide a structural assessment of oral reports, while controlling for individual differences in verbosity.

Nonparametric methods in actigraphy: An update.

Circadian rhythmicity in humans has been well studied using actigraphy, a method of measuring gross motor movement. As actigraphic technology continues to evolve, it is important for data analysis to keep pace with new variables and features. Our objective is to study the behavior of two variables, interdaily stability and intradaily variability, to describe rest activity rhythm.

A fresh look at the use of nonparametric analysis in actimetry.

Actimetry has been used to estimate the sleep-wake cycle instead of the rest-activity rhythm. Although algorithms for assessing sleep from actimetry data exist, it is useful to analyze the rest-activity rhythm using nonparametric methods. This would then allow rest-activity rhythm stability, fragmentation and amplitude to be quantified.

Dream characteristics in a Brazilian sample: an online survey focusing on lucid dreaming.

During sleep, humans experience the offline images and sensations that we call dreams, which are typically emotional and lacking in rational judgment of their bizarreness. However, during lucid dreaming (LD), subjects know that they are dreaming, and may control oneiric content. Dreaming and LD features have been studied in North Americans, Europeans and Asians, but not among Brazilians, the largest population in Latin America.

Sleep and frailty syndrome in elderly residents of long-stay institutions: a cross-sectional study.

Aim: Aging changes sleep patterns in most elderly people. Frailty shares a number of characteristics with sleep disorders and leads to similar results. However, their relationship in residents of long-stay institutions remains unclear.

Neurobiology and clinical implications of lucid dreaming.

Several lines of evidence converge to the idea that rapid eye movement sleep (REMS) is a good model to foster our understanding of psychosis. Both REMS and psychosis course with internally generated perceptions and lack of rational judgment, which is attributed to a hyperlimbic activity along with hypofrontality. Interestingly, some individuals can become aware of dreaming during REMS, a particular experience known as lucid dreaming (LD), whose neurobiological basis is still controversial.

Circadian and homeostatic changes of sleep-wake and quality of life in stroke: implications for neurorehabilitation.

The present study aimed to assess changes in the circadian and homeostatic control of the sleep-wake pattern in stroke patients and correlations with quality of life. Participants were 22 patients (55 ± 12 years) and 24 healthy subjects (57 ± 11 years). Instruments used were: the Pittsburgh Sleep Quality Index, SF-36 Questionnaire and Actigraphy.

Food entrainment: major and recent findings.

Mammals exhibit daily anticipatory activity to cycles of food availability. Studies on such food anticipatory activity (FAA) have been conducted mainly in nocturnal rodents. They have identified FAA as the behavioral output of a food entrained oscillator (FEO), separate of the known light entrained oscillator (LEO) located in the suprachiasmatic nucleus (SCN) of hypothalamus.

Sciatic nerve grafting and inoculation of FGF-2 promotes improvement of motor behavior and fiber regrowth in rats with spinal cord transection.

Purpose: Failure of severed adult central nervous system (CNS) axons to regenerate could be attributed with a reduced intrinsic growing capacity. Severe spinal cord injury is frequently associated with a permanent loss of function because the surviving neurons are impaired to regrow their fibers and to reestablish functional contacts. Peripheral nerves are known as good substrate for bridging CNS trauma with neurotrophic factor addition.

Activation of frontal neocortical areas by vocal production in marmosets.

Primates often rely on vocal communication to mediate social interactions. Although much is known about the acoustic structure of primate vocalizations and the social context in which they are usually uttered, our knowledge about the neocortical control of audio-vocal interactions in primates is still incipient, being mostly derived from lesion studies in squirrel monkeys and macaques. To map the neocortical areas related to vocal control in a New World primate species, the common marmoset, we employed a method previously used with success in other vertebrate species: Analysis of the expression of the immediate early gene Egr-1 in freely behaving animals.

[Brazilian guidelines for the treatment of narcolepsy].

This manuscript contains the conclusion of the consensus meeting of the Brazilian Sleep Association with Brazilian sleep specialists on the treatment of narcolepsy based on the review of medical literature from 1980 to 2010. The manuscript objectives were to reinforce the use of agents evaluated in randomized placebo-controlled trials and to issue consensus opinions on the use of other available medications as well as to inform about safety and adverse effects of these medications. Management of narcolepsy relies on several classes of drugs, namely, stimulants for excessive sleepiness, antidepressants for cataplexy and hypnotics for disturbed nocturnal sleep.

Does the chronotype classification need to be updated? Preliminary findings.

Traditionally, chronotype classification is based on the Morningness-Eveningness Questionnaire (MEQ). It is implicit in the classification that intermediate individuals get intermediate scores to most of the MEQ questions. However, a small group of individuals has a different pattern of answers.

[Brazilian guidelines for the diagnosis of narcolepsy].

This manuscript contains the conclusion of the consensus meeting on the diagnosis of narcolepsy based on the review of Medline publications between 1980-2010. Narcolepsy is a chronic disorder with age at onset between the first and second decade of life. Essential narcolepsy symptoms are cataplexy and excessive sleepiness.

The food-entrainable oscillator: a network of interconnected brain structures entrained by humoral signals?

Food is critical for all animal species. Its temporal availability is a relevant signal for organizing behavioral and physiological parameters. When food is restricted to a few hours per day, rats, mice, and other mammals exhibit anticipatory activity before mealtime (food-anticipatory activity).

Circadian pattern of wheel-running activity of a South American subterranean rodent (Ctenomys cf knightii).

Circadian rhythms are regarded as essentially ubiquitous features of animal behavior and are thought to confer important adaptive advantages. However, although circadian systems of rodents have been among the most extensively studied, most comparative biology is restricted to a few related species. In this study, the circadian organization of locomotor activity was studied in the subterranean, solitary north Argentinean rodent, Ctenomys knightii.

Dissociation of the circadian rhythm of locomotor activity in a 22 h light-dark cycle impairs passive avoidance but not object recognition memory in rats.

We analyzed the effect of dissociation of the circadian rhythm of locomotor activity on the performance in two memory tasks in rats. One group of animals was maintained in a normal 24 h light-dark cycle of 12:12 (T24 group, control). A second group was housed in a 22 h cycle of 11:11 (T22 group, experimental), a condition which is known to produce dissociation of the circadian rhythm of locomotor activity in two components.