Sleep in non-human animals

Abstract: 1. Normal Sleep and Its Variations History Of Sleep Physiology And Medicine Normal Human Sleep: An Overview Normal Ageing Daytime Sleepiness And Alertness Sleep Deprivation Phylogeny Of Sleep Regulation Mammalian Sleep 2. Sleep Mechanisms Brain Electrical Activity And Sensory Processing During Waking And Sleep States Brainstem Mechanisms Generating REM Sleep Basic Mechanisms Of Sleep-Wake States Control Of Motoneurons During Sleep 3. Physiology in Sleep Physiological Regulation in Sleep Cardiovascular Physiology: Central and Autonomic Regulation Cardiovascular Physiology: The Peripheral Circulation Respiratory Physiology: Central Neural Control Respiratory Physiology: Control of Ventilation Respiratory Physiology: Breathing in Normal Subjects Respiratory Physiology: Sleep at High Altitudes Host Defense Endocrine Physiology Gastrointestinal Physiology Temperature Regulation **Sleep-related Penile Erections 4. Chronobiology Introduction: Chronobiology Circadian Rhythms in Mammals: Formal Properties and Environmental Influences Anatomy and Physiology of the Mammalian Circadian System Molecular Genetic Basis for Mammalian Circadian System The Human Circadian Timing System and Sleep-Wake Regulation **Sleep Homeostasis and Models of Sleep Regulation Circadian Rhythms in Fatigue, Alertness and Performance Melatonin in the Regulations of Sleep & Circadian Rhythms 5. Pharmacology Hypnotics: Basic Mechanisms and Pharmacology Hypnotics: Efficacy and Adverse Effects Stimulants: Basic Mechanisms and Pharmacology Stimulants: Efficacy and Adverse Effects Drugs Which Disturb Sleep and Wakefulness 6. Psychobiology and Dreaming Approaches to the Study of Dream Content: Methods Measures

Abstract: The conservation of sleep across all animal species suggests that sleep serves a vital function. We here report that sleep has a critical function in ensuring metabolic homeostasis. Using real-time assessments of tetramethylammonium diffusion and two-photon imaging in live mice, we show that natural sleep or anesthesia are associated with a 60% increase in the interstitial space, resulting in a striking increase in convective exchange of cerebrospinal fluid with interstitial fluid. In turn, convective fluxes of interstitial fluid increased the rate of β-amyloid clearance during sleep. Thus, the restorative function of sleep may be a consequence of the enhanced removal of potentially neurotoxic waste products that accumulate in the awake central nervous system.

Abstract: A series of findings over the past decade has begun to identify the brain circuitry and neurotransmitters that regulate our daily cycles of sleep and wakefulness. The latter depends on a network of cell groups that activate the thalamus and the cerebral cortex. A key switch in the hypothalamus shuts off this arousal system during sleep. Other hypothalamic neurons stabilize the switch, and their absence results in inappropriate switching of behavioural states, such as occurs in narcolepsy. These findings explain how various drugs affect sleep and wakefulness, and provide the basis for a wide range of environmental influences to shape wake-sleep cycles into the optimal pattern for survival.

Abstract: obtain their surface in square centimeters. This simple method provides a means by objective measurements to make evident changes in the surface of wounds that are not apparent to the naked eye. Figure 1 shows the observations recorded with this method in a man of 42 years of age with hemiplegia and a decubital ulcer over the right buttock. The clinicians who had observed this wound daily had not noticed any remarkable change; however, it is quite obvious that the wound grew larger each time the treatment was changed, and that the use of an antibiotic was followed by a particularly striking enlargement of the lesion. In this instance the procedure of projection and gravimetric planimetry was repeated by different operators and a variation of ±5% was found (indicated by a cross-hatched area on Fig. 1). Figure 2 shows the same type of observation in a woman with hemiplegia and a decubital ulcer. This patient died from septicemia, and the decubital ulcer worsened with the general condition of the patient. A method of gravimetric planimetry by standard photographs offers a means to study the course of surface wounds more accurately than by clinical observation or by the pictorial record alone. References

Abstract: Deficits in daytime performance due to sleep loss are experienced universally and associated with a significant social, financial, and human cost. Microsleeps, sleep attacks, and lapses in cognition increase with sleep loss as a function of state instability. Sleep deprivation studies repeatedly show a variable (negative) impact on mood, cognitive performance, and motor function due to an increasing sleep propensity and destabilization of the wake state. Specific neurocognitive domains including executive attention, working memory, and divergent higher cognitive functions are particularly vulnerable to sleep loss. In humans, functional metabolic and neurophysiological studies demonstrate that neural systems involved in executive function (i.e., prefrontal cortex) are more susceptible to sleep deprivation in some individuals than others. Recent chronic partial sleep deprivation experiments, which more closely replicate sleep loss in society, demonstrate that profound neurocognitive deficits accumulate over time in the face of subjective adaptation to the sensation of sleepiness. Sleep deprivation associated with disease-related sleep fragmentation (i.e., sleep apnea and restless legs syndrome) also results in neurocognitive performance decrements similar to those seen in sleep restriction studies. Performance deficits associated with sleep disorders are often viewed as a simple function of disease severity; however, recent experiments suggest that individual vulnerability to sleep loss may play a more critical role than previously thought.