Lewy Body Disease

Lewy body disease, as a postmortem finding, was reported in an 84-year-old man with a 20-year history of RBD, but without any clinically detected neurological disorder (Uchiyama et al., 1995). Postmortem histopathological examination revealed that the patient had Lewy body disease with marked decrease of pigmented neurons in the locus ceruleus and substantia nigra. These findings represent the first documented evidence of a loss of brain stem monoaminergic neurons in clinically idiopathic RBD,...

Postictal State

Seizures that helps in distinguishing them from complex partial seizures (Delgado-Escueta et al., 1983). A lack of postictal confusion after seizures may also be seen in children with supplementary sensorimotor seizures (Connolly et al., 1995). The postictal period in complex partial seizures can vary in length usually from 2 to 10 min and is characterized by disorientation and inattention with very little motor activity (Goldensohn and Gold, 1959 Malamudu, 1967 Mohan et al., 1975). There is...

Temporal Lobe Epilepsy

In Billiard's (1982) study of 127 patients, 9.4 had sleep-related complex partial seizures. In a study of 50 patients with sleep-related complex partial seizures, Cadilhac (1982) found that 32 patients had seizures in NREM sleep, 8 in REM sleep, and 10 in both states. However, in a study of 10 patients with a diagnosis of mesial temporal lobe epilepsy, Montplaisier (1985) found that none of these patients had seizures in NREM sleep. In a study of 15 patients with temporal lobe epilepsy, only 7...

Neuropsychological Deterioration

The majority of patients have normal neuropsychological and motor functions prior to the onset of ESES, as exemplified by 18 of the 29 patients reported by Tassinari et al. (1992b), 23 of the 31 cases described by Morikawa et al. (1989), and 30 of the 43 patients discussed by Dalla Bernardina et al. (1989). The remaining patients have abnormal development prior to the occurrence of ESES. All cases exhibit further, and often severe, decrease in function during the stage of ESES. The disturbances...

Electrical Status Epilepticus Of Sleep

Electrical status epilepticus of sleep (ESES) refers to the occurrence of continuous epileptiform activity for at least 85 of slow-wave sleep. This syndrome is also known as epilepsy with continuous spike waves during slow-wave sleep. The syndrome was first described by Patry (1971). The EEG is characterized by generalized spike-wave complexes at 2-2.5 Hz. There is a marked attenuation of the pattern during REM sleep and in the wake EEG. The condition almost always occurs in patients with a...

Ekg During Sleep

Figure 13.1 REM sleep polysomnograms demonstrating the necessity of extensive extremity EMG monitoring in documenting RBD. (A) Shows customary REM sleep, with its distinct electrophysiological profile the triad of dense, high-voltage REMs (1 -2), activated EEG (3-5), and chin EMG atonia with one minor burst of phasic twitching (6). Channels 1 -6 are sufficient for scoring sleep stages throughout the night, according to the standard methods and criteria of Rechtschaffen and Kales. However, (B)...

Differential Diagnosis

The differential diagnosis of arousal disorders depends on the types of behaviors that occur. For patients with sleep terrors or sleepwalking, diagnostic considerations may include nightmares, REM sleep behavior disorder (RBD), epilepsy, nocturnal delirium, panic disorder, and dissociative states. Timing of episodes, the length of time required to attain full alertness after an episode, and amount of recall are helpful distinguishing features. Sleep terrors and sleepwalking usually begin with...

F3c3 C3p3

FIGURE 6.2 EEG from scalp and sphenoidal electrodes during wakefulness, sleep stage 3 and REM sleep for this same patient with a temporal lobe focus. Spl and Sp2 are the left and right sphenoidal electrodes. Note similarity of spiking fields in wakefulness and REM sleep and bilateral independent temporal spiking in stage 3. There is maximal focalization of spiking during REM sleep. (From Sammaritano, M., et al., Interictal spiking during wakefulness and sleep and the localization of foci in...

Info

FIGURE 8.1 The four basic mechanisms of sleep regulation. The clock time is reported on the x-axis. In homeostatic and circadian (W, wakefulness S, sleep). In ultradian (SWA, slow-wave activity). In cyclic alternating pattern (CAP) SI, stage 1 REM, rapid eye movement sleep S2, stage 2 S3, stage 3 S4, stage 4). duration of sleep episodes is strongly influenced by the phase of the body temperature rhythm. Decreasing temperature, as occurs in the nocturnal hours, is combined with longer sleep...

Predictors Of Sleepiness In Epilepsy

Several factors have been identified as predictors of sleepiness in persons with epilepsy using the Epworth Sleepiness Scale as a subjective measure of daytime sleepiness (Malow et al., 1997 Sanchez de Leon et al., 1997). The ESS is a self-administered, eight-item questionnaire designed to ascertain sleep propensity in a variety of everyday situations (Johns, 1992). The scale has been validated in a variety of situations, and was found to correlate with results of the MSLT, the gold standard...

Postictal Lethargy

The postictal state is an ambiguous and poorly understood phenomenon. The means by which the various pathophysiological mechanisms produce differing postictal manifestations are still unknown. It is commonly assumed that various phenomena seen in the postictal state represent a manifestation of neuronal exhaustion in a selected neuronal pool. The clinical symptomatology of the postictal state is almost as diverse as the variations of ictal semiology. The postictal period correlates to a time in...

Normal Rem Sleep

Rem Without Atonia

y -ttMH B REM SLEEP WITHOUT EES DESYNCHRONY B REM SLEEP WITHOUT EES DESYNCHRONY FIGURE 3.9 Evoked kindled seizures during REM sleep before A and after atropine B or pontine dissociation techniques. At B , atropine creates a SWS-like EEG synchrony in REM and selectively increased incidence of EEG seizure susceptibility in REM without clinical motor accompaniment. At C , pontine lesions that caused REM sleep without atonia selectively increased clinical motor accompaniment. Paper speed is 15 mm....

T8p8

It has been estimated that simply repeating the EEG at another point in time may increase the yield by 20 Salinsky et al., 1987 Pratt, 1968 Fountain etal., 1998 . Studies comparing sleep deprived EEG with drug-induced sleep EEGs have reported conflicting findings, some finding greater activation of ED with drug-induced sleep Degen and Degen, 1981, 1983, 1991 Veldhuisen, 1983 Degen et al., 1987 . Others Sherwin and Hooge, 1973 Rumpl et al., 1977 Rowan et al, 1982...

Mark S Scher

Department of Pediatrics Pediatric Neurology Pediatric Epilepsy and Sleep Programs Rainbow Babies and Children's Hospital University Hospitals of Cleveland Case Western Reserve University Cleveland, Ohio Unique Aspects of the Ultradian Sleep Rhythm of the Fetus and Neonate Epileptic Syndromes during Neonatal Infancy Periods Benign Familial Neonatal Infantile Convulsions Benign Epilepsies of Infancy Early Infantile Epileptic Encephalopathy Infantile Spasms or West Syndrome Severe Epileptic...

Drowsiness

Electrocorticography

FIGURE 10.1 EEG recording in a 7-year-old male child with LKS and ESES. This child started to suffer, at the age of 5 years, from rare partial seizures characterized by clonic jerks on the left side of the face, with occasional secondary generalization. At the same age a regression of language skills and behavioral disorders appeared. At the age of 6 years, a sleep EEG recording showed continuous paroxysmal activities compatible with ESES. Left panel, an awake EEG demonstrated normal background...

Frontal Lobe Epilepsy

Patients with FLE may present with one of three distinct clinical seizure types 1 asymmetrical tonic seizures SSMA , 2 focal motor seizures, and 3 complex partial seizures Salanova et al, 1995 . Patients with SSMA seizures frequently have asymmetrical tonic involvement of the extremities, at times assuming a typical fencing posture. There may be associated vocalization, thrashing movements, and kicking with preserved responsiveness. The seizures are usually brief in duration, less than 30 s,...

Min

Ontogeny Eeg

C CONTINUOUS EEG PROTOTYPICAL REM D DISCONTINUOUS EEG PROTOTYPICAL NREM PCA POST CONCEPTIONAL AGE MIN MINUTE M MIXED FREQUENTLY ACTIVE SLEEP REM HVS HIGH VOLTAGE SLOW NREM TA TRACE ALTERNANT NREM LVI VOLTAGE IRREGULAR REM FIGURE 7.2 Differences in sleep onset architecture and cycle length among fetal, neonatal, and infancy sleep cycles. PCA, coalesces over successive sleep cycles after 36 weeks PCA. A weak diurnal effect is also present in the preterm neonate, like the fetus, as illustrated by...

Neonatal Seizures

Neonates with seizures are not primarily associated with epileptic syndromes, with or without sleep activation Scher, 1997 . Newborns largely express seizures as part of transient acute encephalopathic states or severe chronic encephalopathies. Children with brain disorders because of hypoxic ischemic encephalopathy, brain infections, or cerebrovascular disease, for example, present with seizures exclusively during neonatal period, with a risk for epilepsy approximating 20 . Commonly, neonates...

Lesional Epilepsy With Frontotemporal Focus

A powerful activating effect of CAP-related events has been described also for interictal epileptic discharges in temporal lobe epilepsy TLE with a spike frequency significantly higher p lt .03 in phase A 1.71 spikes per minute than in phase B .736 spikes per minute . This study also revealed an intermediate activating effect of NCAP 1.18 spikes per minute between phase A and phase B Loh et al, 1997 . Patients with focal lesional frontotemporal lobe epilepsy FTLE Fig. 8.6 show significant IID...

Lt

Photoconvulsive Response

FIGURE 3.4 A REM transition photoconvulsive response PCR elicited by 20 per second photic stimulation PS . PS onset and offset are indicated by arrows. The PS initially evoked epileptiform K-complexes in the kindled AMY and ipsilateral LGN, followed by EEG seizure discharge propagation with clinical accompaniment. Paper speed is 10 mm. Abbreviations as in Fig. 3.2. FIGURE 3.4 A REM transition photoconvulsive response PCR elicited by 20 per second photic stimulation PS . PS onset and offset are...

To

FIGURE 13.3 REM sleep polysomnogram same patient and same night as shown in Fig. 13.2, revealing selective, dense, high-voltage left flexor arm EMG twitching 9 in conjunction with observed grabbing and squeezing behaviors of the left hand. A burst of REMs 1-2 precedes these gross behaviors. The EEG 3-6 is activated, the chin EMG 7 has minimal tone with occasional twitching, and the leg EMGs 12-15 are completely inactive. Adapted from Mahowald, M. W and Schenck, C. H. 1990 . REM Sleep Behavior...

Microarchitecture Of Sleep And Epilepsy

Terzano et al. 1985 introduced a new methodology to study the microarchitecture of NREM sleep. Each stage of NREM sleep is divided into periods of transient fluctuations of arousal referred to as cyclic alternating pattern CAP . This CAP is then superimposed on a relatively homogeneous background of EEG activity, lasting for more than 60 s in duration, referred to as non-CAP. The CAP consisted of two phases, CPAP-A, which is characterized by a paroxysm of phasic activity, representing a state...

Sudden Unexplained Nocturnal Death

Sudden unexplained nocturnal death SUND is a rare disorder in which apparently healthy adults die suddenly during sleep. It thus resembles sudden infant death syndrome. Young and middle-aged men from Southeast Asian countries including the Philippines, Japan, Thailand, Vietnam, Cambodia, and Laos are most often affected Sugai, 1959 Aponte, 1960 Baron et ai, 1983 . The syndrome has been recognized for almost a century, but attracted increased attention following the immigration to the United...

Sec

FIGURE 3.5 Photic stimulation, as described in Fig. 3.4, was applied in waking or REM sleep. Localized epileptiform activity resembling phasic arousal events can be seen in the kindled AMY, ipsilateral LGN, and motor cortex. Seizure discharge could outlast the stimulus black bars on bottom channel , as seen in drowsy wakefulness top right . Epileptiform EEG discharge was most difficult to obtain in REM sleep bottom panels , and no clinically evident seizure activity was detected in this state....

Spindles

Sleep spindles are made of the association of two distinct rhythms 1 waxing and waning waves at 7-14 Hz within sequences lasting for 1-2 s and 2 periodic recurrence of spindle sequences with a slow rhythmicity of about 0.2-0.5 Hz Fig. 2.IB . These rhythms accompany sleep onset mostly stage 2 , although their presence in deeper sleep stages 3 and 4 has been well documented Niedermeyer, 1999 . Spindles are generated within the thalamus, but their shape and synchronization are influenced by the...

Benign Epilepsy Of Childhood With Centrotemporal Spikes

Five main features Distinguish BECTS from the ESES Syndrome 1. Sleep may enhance the discharges in BECTS but an SW index greater than 85 was not reported in two large BECTS series studied by means of nocturnal polygraphy Bureau, 1995a Ambrosetto, personal communication . At variance with these studies, a true ESES has been described in some cases of BECTS after the introduction of carbamazepine Cara-ballo et al., 1989 . Dalla Bernardina et al. 1989 also described 20 cases of BECTS associated...

Penicillin Epilepsy

Injection of large dosages of penicillin 300,000-400,000 IU kg, i.m. Fig. 3.1, top induces seizure manifestations of primary generalized epilepsy, particularly juvenile myoclonic epilepsy Gloor, 1979 . This is the prototypic epilepsy on awakening at least with respect to convulsions Janz, 1962 . Spike-wave and multi-spike-wave complexes with myoclonic jerks accompany sleep EEG transients such as sleep spindles and K-complexes during slow-wave sleep SWS , the feline equivalent of human NREM, and...

Clinical Features Of Rapid Eye Movement Sleep Behavior Disorder

Although various PSG and clinical features of RBD have been identified by investigators from three continents since 1966 Mahowald and Schenck, 1994 , RBD was not formally recognized and named until 1986-1987 Schenck et al., 1986 Schenck et al., 1987 . RBD was incorporated within the international classification of sleep disorders ICSD in 1990. A typical clinical presentation of RBD is as follows Schenck et al., 1986 A 67-year-old dextral man was referred because of violent behavior during sleep...

Generalized Epilepsy and Sleep

Department of Neurology University of Munich Munich, Germany Relations of Epileptic Seizures to Sleep-Wake Cycle Sleep Pattern of Patients with Generalized Epilepsy Relation of Epileptiform Discharges to the Sleep-Wake Cycle and Sleep Stages in Generalized Epilepsy Sleep Deprivation Effects of Antiepileptic Drugs on Sleep There are several relationships between generalized epilepsy and sleep, both clinically and electroencephalographically. It has been known since the days of Aristotle...

Phasic Event Arousal

FIGURE 3.3 Continuous 2-min polygraphic recording of an evoked phasic arousal event, in this case a high-amplitude sleep spindle, by an accidental loud noise that precedes a convulsion. The spindle in the motor cortex lead channel 1 was of such high voltage as to displace the pen from the recording. Paper speed is 10 mm. Abbreviations as in Fig. 3.2. FIGURE 3.3 Continuous 2-min polygraphic recording of an evoked phasic arousal event, in this case a high-amplitude sleep spindle, by an accidental...

Other Sleeprelated Paroxysmal Events

Other sleep-related paroxysmal events were identified as epileptic as well. Peled and Lavie 1986 described 14 patients with hypersomnia secondary to recurrent nocturnal arousals, which were shown to be associated with paroxysmal epileptiform discharges occurring exclusively during stage 2 or 3 of NREM sleep three patients showed dramatic improvement after treatment with anticonvulsants. Montagna et al. 1990 made similar observations, concluding that, even though epileptic in nature, paroxysmal...

Effects Of Cyclic Alternating Pattern On Epileptic Events

Across the years, several authors have focused their attention on the dynamic relationship between epileptic paroxysms and EEG phasic events during sleep. In the feline generalized penicillin epilepsy, spike-and-wave discharges are thought to represent a pathological cortical response to afferent thalamocortical volleys, which under normal conditions are involved in sleep spindling Gloor, 1984 . In the feline amygdala-kindled model, which is generally assimilated to human temporal epilepsy...

Prakash kotagal

Section of Pediatric Epilepsy and Sleep Disorders Center Cleveland Clinic Foundation Cleveland, Ohio Effect of Sleep on Epileptiform Discharges Activating Effect of Sleep Deprivation on Epileptiform Discharges on the Electroencephalogram Effect of Sleep Deprivation on Seizures Effect of Seizures on Nocturnal Sleep and Daytime Function As far back as the last century, the relationship of seizures to sleep has been noticed. Gowers reported that 21 of epileptics had seizures predominantly during...

Diagnosis

Because only 20 of bruxist episodes are accompanied by noise, the majority of bruxists are unaware of their bruxing. Wear patterns on the teeth, tooth mobility, and fracture cusps suggest bruxing activity. Other individuals come to medical attention because of muscle or joint pain, fatigue, stiffness on waking, or headaches. The rhythmic myogenic artifact resulting from bruxism appearing on a polysomnogram has a characteristic appearance Fig. 12.2 . FIGURE 12.2 Chewing movements produced by...

Psychogenic Seizures

Psychogenic seizures usually manifest during the individuals' daytime waking hours. However, on rare occasions individuals may present with paroxysmal events restricted to the sleep period. Video recording of such patients demonstrates that the patient awakens from sleep and the EEG demonstrates a normal waking EEG pattern prior to and during the time of the recorded paroxysmal event. In addition to the normal EEG pattern during the ictus, the clinical features of the psychogenic seizure often...

References

Abe, K., Amatoni, M., and Oda, N. 1984 . Sleepwalking and recurrent sleeptalking in children of childhood sleepwalkers. Am. J. Psychiatry 141 800-801. Aldrich, M. S., and Jahnke, B. 1991 . Diagnostic value of video-EEG polysomnography. Neurology 41 1060-1066. American Psychiatric Association. 1994 . In Diagnostic and Statistical Manual of Mental Disorders DSM-1V 4th edition , Washington, DC American Psychiatric Association. American Sleep Disorders Association. 1997 . In International...

Diagnostic Evaluation

Hypersynchronous Delta Activity

For many patients, the history is sufficient to diagnose an arousal disorder no laboratory studies are required. For example, typical episodes of sleepwalking or sleep terror that occur in children or young adults generally do not require additional evaluation. Diagnostic studies are more often needed if the history has atypical features, such as stereotyped behaviors, frequent occurrence in the second half of the night, or onset during adulthood. Definitive diagnosis with laboratory studies...

Cyclic Alternating Pattern And Noncyclic Alternating Pattern

CAP is organized in sequences of two or more CAP cycles. Each CAP cycle consists of a phase A and a phase B, each lasting between 2 and 60 s. All CAP sequences begin with a phase A and end with a phase B. In NREM sleep, the phase A patterns are composed of the single or clustered arousal-related phasic events peculiar to the single sleep stages Intermittent alpha rhythms and sequences of vertex sharp waves, in stage 1 Sequences of two or more K-complexes with or without alphalike components and...

Hypogenic Paroxysmal Dystonia Or Epilepsy

Lugaresi and Cirignotta 1981 described five patients with recurrent nocturnal episodes of agitation during nonrapid eye movement NREM sleep, consisting of violent limb movements and tonic spasms of 15-45-s duration with preserved consciousness, responsive to carbamazepine. Impressed by the resemblance of these clinical manifestations to the attacks of paroxysmal kine-sigenic choreoathetosis and the absence of epileptiform EEG changes, they coined the term hypnogenic paroxysmal dystonia....

Nocturnal Dissociative Disorder

In dissociative disorder, the major symptom is a disruption of consciousness, identity, memory, or perception that has a psychogenic basis. If the disturbance affects consciousness primarily, awareness is dissociated from behavior and patients engage in complex behaviors for which they are amnestic. Identity is primarily affected in depersonalization disorder and multiple personality disorder American Psychiatric Association, 1994 . While prolonged nocturnal fugues occur in some patients, brief...

Rhythmic Movement Disorder

Rhythmic movement disorder, characterized by stereotyped repetitive movements of the head and neck, or sometimes the trunk, is also called head-banging, head-rolling, body-rocking, or body-rolling depending on the type of movement. Other terms sometimes employed include jactatio capitis nocturna and rhythmie du sommeil. The movements occur during drowsy wakefulness and stage 1 sleep at a rate of 0.5-2 Hz, rarely during deeper stages of NREM or REM sleep, and may last from a few seconds to as...

Parasomnia Overlap Disorder

Our center has reported on a group of 33 RBD patients with PSG-docu-mented overlapping NREM-REM sleep motor parasomnias consisting of sleepwalking, sleep terrors, and RBD Schenck et al., 1997b . Mean age was 34 14 years mean age of parasomnia onset was 15 16 years range 1-66 70 n 23 were males. An idiopathic subgroup n 22 had a significantly earlier mean age of parasomnia onset 9 7 years than a symptomatic subgroup n 11 27 23 years whose parasomnia began with neurological disorders, n 6...

Nonepileptic Behaviors During Sleep

Hypsarrhythmic Ecg Pattern

Nonepileptic disorders during sleep can be mistaken for epilepsy Herrmann et al., 1993 Scher and Vigevano, 1997 Fusco et al., 1999 . Three groups of patients with which potential diagnostic errors can be made have been discussed. First, LAN N. 6 mths SVP 68 111 100pV _ FIGURE 7.8A Example of infantile spasms at 5 months of age, showing an interictal recording with atypical hypsarrhythmia, with continuous and asynchronous spike and wave activity during the waking state. From Dulac, O., et al.,...

Pharmacological Manipulations In Cataplexy

Several compounds have been administered intravenously i.v. during H-reflex studies and during long-term investigation of cataplexy in humans more sophisticated studies have been performed using animal models, particularly narcoleptic-cataplectic Dobermans Delashaw et al., 1979 Foutz et al., 1981 Mignot et al., 1988 . The effects of REM sleep-modulating agents and tricyclic antidepressant compounds have been investigated. Compounds with norepinephrine and serotonin reuptake-blocking properties...

Postictal Sleep

Postictal sleep is a common phenomenon after a generalized tonic-clonic seizure. The patient may pass through several stages from sleep to delirium to drowsiness before awakening. During the late postictal state, the heart rate begins to normalize from the typical ictal tachycardia. There is a decrease in muscle tone with bladder sphincter relaxation and incontinence that typically occurs in the early postictal phase. In the immediate postictal phase, there is partial obstruction of the airway...

Electrooculography

The electrooculogram EOG is the second parameter necessary for differentiating sleep stages, and at least two channels are the recommendation. Electrodes can be placed 1 cm lateral to and above one outer canthus, while a second is placed 1 cm lateral to and below the contralateral outer canthus. By referencing these electrodes either to one or to both ear or mastoid electrodes Al, MN1 , horizontal, vertical, and oblique eye movements can all be recorded. If the need arises to distinguish...

Benign Focal Epilepsy Of Childhood

The syndrome of benign focal epilepsy of childhood, also referred to as benign rolandic epilepsy or benign childhood epilepsy with centrotemporal spikes, is a common form of childhood epilepsy. The children are of normal intelligence, have a normal neurological examination, and present with sleep-related seizures. Approximately 75 of the seizures occur during sleep Lerman and Kivity, 1975 Loiseau et al, 1973 . The seizures are focal motor usually involving the face and arm , present with...

Association Of Rapid Eye Movement Sleep Behavior Disorder With Specific Human Leukocyte Antigen Haplotypes

Narcolepsy, like RBD, is a prominent disorder of REM sleep dysregulation. Narcolepsy has a very strong association with HLA class II genes, with the DQB 1 0602 DQwl group allele being expressed in nearly all cases. Our center performed HLA class II antigen phenotyping in a group of 25 Caucasian males who had RBD but not narcolepsy 84 n 21 were DQwl DQB 1 05,06 positive and 28 n 7 were DR2 positive DQB 1 0501 n 9 and DQB 1 0602 n 7 were the most common phenotypes Schenck et al., 1996b . The 84...

Effects Of Seizures On Sleep And Vigilance

Seizures occurring both at night and during the day can affect sleep architecture and produce daytime sleepiness. In a study comparing the effects of generalized and focal seizures on sleep, nocturnal generalized seizures produced a decrease in sleep time and reduced REM sleep percentage, prolongation of REM latency, and more sleep fragmentation Touchon et al., 1991 . Stages 1 and 2 sleep were increased while the percentage of slow-wave sleep SWS was unchanged. REM rebound an increase in REM...

Mario Giovanni Terzano

Sleep Disorders Center Department of Neurology University of Parma Italy Epilepsy and Vigilance States Sleep Propensity and Body Temperature Rhythms Sleep Intensity and Slow-Wave Sleep Nonrapid Eye Movement Rapid Eye Movement Sleep Cycle Dynamics of Thalamic Neurons during Sleep Low-Frequency lt 1 Hz Oscillations in the Human Sleep Electroencephalogram Cyclic Alternating Pattern as a Marker of Sleep Instability Scoring of Cyclic Alternating Pattern Parameters Cyclic Alternating Pattern and...

Cyclic Alternating Pattern Rate

CAP time is the temporal sum of all CAP sequences. CAP time can be calculated throughout total NREM sleep and within the single NREM stages. The percentage ratio of CAP time to sleep time is referred to as CAP rate. CAP rate can be measured in NREM sleep percentage ratio of total CAP time to total NREM sleep time and in the single NREM stages percentage ratio of CAP time in a given stage to the total duration of that stage throughout sleep . In human sleep, CAP rate is an index of arousal...