Rapid eye movement sleep eye movements in schizophrenia and depression.

OBJECTIVE: To investigate the specificity of rapid eye movement (REM) sleep eye movement measures in schizophrenics, depressives, and nonpsychiatric controls. DESIGN: Survey. SETTING: Inpatient psychiatric hospital. STUDY PARTICIPANTS: Volunteer sample of male veterans who met Research Diagnostic Criteria (RDC) for schizophrenia (n = 21) or major depressive disorder (n = 24), or male veterans recruited from the community with no history of psychiatric illness (n = 13). Patients with a concurrent RDC diagnosis of alcoholism were excluded. After data collection, three schizophrenics, two depressives, and one nonpsychiatric control were eliminated because of two or fewer REM periods on either of the two recording nights. INTERVENTION: None. MAIN OUTCOME MEASURE: Computer-detected total night and within-night measures of REM sleep eye movement density, ie, the ratio of eye movement counts to stage REM minutes. RESULTS: Using a 95% confidence interval, schizophrenics, depressives, and nonpsychiatric controls did not differ in total night or within-night measures of eye movement density. Within nights, eye movement density increased across REM periods in the schizophrenics and nonpsychiatric controls; the depressives showed a flatter within-night distribution associated with their older age. CONCLUSIONS: A broad range of REM sleep eye movement densities characterize both schizophrenics and depressives and substantially overlaps the normal range. Abnormalities of REM sleep eye movement activity should not be considered a biological marker for affective illness.

Abnormal rapid eye movement latencies in schizophrenia.

Several previous studies have observed short rapid eye movement (REM) latencies in schizophrenic patients without major affective disorder. This study was designed to meet several of the criticisms of those previous studies. Using Research Diagnostic Criteria, we compared the sleep patterns of schizophrenic patients with those of normal controls and patients with major depressive disorder and schizoaffective disorder. All patients were medication free, and REM latency was explicitly defined using both strict and lenient criteria. Chronically ill paranoid or undifferentiated schizophrenics could not be distinguished from patients with major depressive disorder or schizoaffective disorder using any definition of REM latency. These results were not due to longer REM latency in the particular sample of patients with major depressive disorder. They had abnormally low REM latencies; however, the schizophrenic patients showed similar decrements. These data cast serious doubt on the specificity of short REM latency as a biological marker for major depressive disorder.

Psychophysiological correlates of the practice of Tantric Yoga meditation.

Autonomic and electroencephalographic (EEG) correlates of Tantric Yoga meditation were studied in three groups of subjects as they progressed from normal consciousness into meditation. Groups differed in their level of meditation proficiency. Measures of skin resistance, heart rate, respiration, autonomic orienting responses, resting EEG, EEG alpha and theta frequencies, sleep-scored EEG, averaged evoked responses, and subjective experience were employed. Unlike most previously reported meditation studies, proficient meditators demonstrated increased autonomic activation during meditation while unexperienced meditators demonstrated autonomic relaxation. During meditation, proficient meditators demonstrated increased alpha and theta power, minimal evidence of EEG-defined sleep, and decreased autonomic orienting to external stimulation. An episode of sudden autonomic activation was observed that was characterized by the meditator as an approach to the Yogic ecstatic state of intense concentration. These findings challenge the current "relaxation" model of meditative states.

Three therapeutic communities. A prospective controlled study of narcotic addiction treatment: process and two-year follow-up results.

The efficacy of three different residential therapeutic communities for male veterans addicted to heroin was studied, comparing 181 subjects who were randomly assigned to one of the communities with 166 subjects briefly hospitalized only for the treatment of withdrawal symptoms. At two-year follow-up, subjects from both a professionally staffed community and a peer confrontation community were found significantly more likely than the withdrawal-only group to be working or attending school and less likely to have been convicted of a crime. An eclectic program employing both professionals and paraprofessionals was not found to exceed the withdrawal-only group on any of the major outcome variables. The two relatively successful communities, although different in structure and style, were both perceived by their residents to have greater program clarity, order, staff control, and orientation to personal problems than the unsuccessful program.

Therapeutic communities vs methadone maintenance. A prospective controlled study of narcotic addiction treatment: design and one-year follow-up.

This study compares the efficacy of three residential therapeutic communities and an outpatient methadone maintenance program for 585 male veterans addicted to heroin. Subjects were randomly assigned to the treatment modalities. More than 93% of the subjects completed both six- and 12-month questionnaires. In this report, the treatment settings, characteristics of the sample, assignment protocol, and pattern of treatment entry and first-year follow-up results are outlined. The various clinical demands that affected the research protocol, the degree to which the randomization was compromised, and the implications for the analysis of outcome are discussed. One year after admission to the study, subjects who had been in a therapeutic community for longer than seven weeks or in methadone treatment were more likely to be employed or attending school, and less likely to be in jail, using heroin, or to have been convicted of a serious crime, than subjects who received no treatment at all beyond a short detoxification period. Those who spent less than seven weeks in a therapeutic community were doing no better than subjects in the no treatment group.

Markovian analysis of phasic measures of REM sleep in normal, depressed, and schizophrenic subjects.

Rapid eye movement (REM) phasic activity refers to brief events that occur in periods of REM sleep, such as individual eye movements (EMs). REM density (RD) is the best-known measure of such activity, although reports of RD differences among normal, depressed, and schizophrenic subjects have been equivocal. RD is a measure with a large variability, and its physiological substrate is not known. We sought a more consistent measure which might also suggest the underlying physiology. Using the time intervals between individual EMs, we calculated empirical probability distributions which showed that EMs fell into two subgroups or states: "burst" and "isolated." Then, a novel Markov chain model of sequential transition between the states was calculated for nine normal, eight schizophrenic, and seven depressed male veterans. A significantly higher probability of remaining in the burst state was observed in both patient groups. The actual number of EMs in the isolated state was nearly identical in the three groups. Possible pontine neurochemical explanations involving cholinergic and serotonergic mechanisms are discussed.

REM latency in Alzheimer's disease.

Latency to the first episode of rapid eye movement sleep (REML) has been proposed as a potential biomarker for Alzheimer's disease (AD). In this study, we compared REML values from 28 AD patients and 28 age- and sex-matched controls. We employed multiple definitions of REML and multiple cutoffs to classify patients and controls. Results indicated that the best REML definition and optimal cutoff criterion resulted in only 65% correct classifications. We discuss the longer REML in AD patients relative to controls in terms of both overall sleep disturbance and selective deterioration of the REM-cholinergic system. As REML may be relatively short in other forms of psychopathology (e.g., affective disorders), REML may still hold promise in the differential diagnosis of dementia and pseudodementia.

Effects of 5-hydroxytryptophan on fragmentation of REM sleep in alcoholics.

The authors studied the effects of oral loading with 5-HTP on REM fragmentation in a group of alcoholics who were abstinent following acute ethanol withdrawal. Decreased fragmentation was found in the majority of subjects, and those subjects with low baseline REM efficiency (i.e., greater fragmentation) showed more improvement from the drug than did subjects who were less impaired initially. The authors suggest that there is an organic decrement of serotonin during ethanol withdrawal which is partially reversed by 5-HTP loading.

Middle ear muscle activity during REM sleep in schizophrenic, schizoaffective and depressed patients.

The authors measured the middle ear muscle activity during REM sleep of normal subjects (N = 13) and patients with schizophrenia (N = 11), schizoaffective disorder (N = 8), or major depressive disorder (N = 10). The rates of middle ear muscle activity for 5 schizophrenic patients were higher than the highest rates of the other groups. The patients with major depressive disorder had normal rates, and the rates of those with schizoaffective disorder were below normal. Within the schizophrenic patients, high middle ear muscle activity could not be directly attributed to background sleep disturbances, age, anxiety, depression, or diagnostic subtype.

Self-reports versus sleep laboratory findings in 122 drug-free subjects with complaints of chronic insomnia.

The authors compared the sleep laboratory recordings of 122 drug-free subjects who complained of chronic insomnia with the subjects' estimates of their habitual sleep characteristics and their estimated sleep time on the morning after sleeping in the laboratory. Most subjects consistently underestimated the amount of time they slept and overestimated the amount of time it took them to get to sleep in comparison with laboratory data. All subjects consistently underestimated the number of arousals they experienced. The authors discuss the implications of these findings for the treatment and definition of insomnia and for further research.

Middle ear muscle activity (MEMA) in schizophrenia using a noninvasive technique.

Rapid eye movement (REM) sleep middle ear muscle activity (MEMA) was recorded in four diagnostic groups: schizophrenics (n = 18), schizoaffectives (n = 8), depressives (n = 11) and healthy, nonpsychiatric controls (n = 10). Previous work suggested that schizophrenics have higher than normal rates of REM sleep MEMA; this previous study employed the MEMA recording technique of impedance audiometry, which involves a 90-dB stimulus probe tone. The present study, which utilized a silent, pressure-sensitive transducer (i.e. no acoustic stimulus), was undertaken to determine if the stimulus tone might have elicited excess MEMA in the schizophrenics. In this present study, we observed no significant differences in REM sleep MEMA among the four diagnostic groups, suggesting that REM sleep MEMA cannot be used as a biological marker to differentiate clinical disorders. This failure to replicate our previous finding of high MEMA rates in schizophrenics is likely due to sampling error; alternatively, high REM sleep MEMA rates might be elicited in a subgroup of schizophrenics with an acoustic stimulus.

Phasic events of REM sleep: phenomenology of middle ear muscle activity and periorbital integrated potentials in the same normal population.

Both periorbital integrated potentials (PIPs) and middle ear muscle activity (MEMAs) were recorded in a sample of normal male veterans. Activity measures were constructed for each REM period and for the 10 min preceding and following each REM period. PIPs and MEMAs displayed high levels of internight reliability. PIPs were more abundant than MEMAs; in REM the average PIP rate was almost 8 times the average MEMA rate. Within REM, the proportion of MEMAs and PIPs with concurrent eye movement activity was very similar, 66 and 70%, respectively. Both PIPs and MEMAs had higher rates within REM than within NREM. NREM PIP activity was similar both before and after the REM period, whereas NREM MEMA activity was higher before the REM period than after the REM period. Within REM, the distribution of PIPs and MEMAs was similar for REM periods exceeding 30 min. Within-night trends could nor be established for MEMAs due to limitations of the recording technique; PIPs, however, were generally highest in the middle of the night but still higher at the end of the night than at the beginning. Correlations with psychometric test data showed PIP rate in REM to be related to the psychoticism scale of the Minnesota Multiphasic Personality Inventory and MEMA rate in REM to be inversely related to the Barron Ego Strength scale. No associations were found between the psychometric data and measures of PIP and MEMA leakage from REM into NREM. The potential for pathological intrusion of REM phasic events into the waking stage might be conceptualized in terms of a general ungating of activity with PIP and MEMA rates increasing in both NREM and REM alike.

Evidence for the role of serotonin in the regulation of slow wave sleep in schizophrenia.

Nocturnal sleep data and cerebrospinal fluid (CSF) concentrations of the biogenic amine metabolites were measured in 20 male schizophrenics. Consistent with other reports of a stage 4 sleep deficit in schizophrenia, measures of stage 4 sleep were low relative to normal reference data. Measures of stage 4 sleep in absolute amounts and corrected for total sleep were positively correlated with CSF concentrations of the serotonin metabolite, 5-hydroxyindole acetic acid (5-HIAA). CSF 5-HIAA was also correlated with measures of stage 3 sleep and total sleep time suggesting that serotonin may modulate the amount of slow wave sleep broadly defined and possibly sleep duration. Total stage 4 time was also correlated with the dopamine metabolite HVA; consequently, the specificity of the finding might be limited. Also, in this study, schizophrenia was used as a particular model for stage 4 deficits; however, the association of measures of stage 4 sleep with CSF levels of 5-HIAA is not thought to be specific to schizophrenia.

An inexpensive alternative for recording middle ear muscle activity (MEMA) during sleep.

In past studies of middle ear muscle activity (MEMA) in sleep, one of two methods of recording has been used: an acoustic impedance bridge (AIB) or a miniaturized pressure transducer (MPT). A low-cost and less fragile piezoresistive pressure transducer was tested to determine its practicality in recording MEMA during sleep in humans. A specialized ear mold accommodating both types of pressure transducer was custom-fitted for six subjects. The sleep of each subject was analyzed epoch by epoch for one night to determine comparability of the two transducers. In no case did either transducer indicate a MEMA without confirmation by the other. It is recommended that this type of transducer would be practical for researchers interested in recording MEMA in sleep.

Middle-ear muscle activity (MEMA) and its association with motor activity in the extremities and head in sleep.

Middle-ear muscle activity (MEMA) in sleep was simultaneously recorded from both ears using extratympanic manometry. Head movement, speech movements, ankle flexion and wrist movement were monitored by electromyographic recording using surface electrodes at the back of the neck, second laryngeal notch, anterior tibialis and forearm muscle. Motor events recorded from these electrode placements were examined for correlation with MEMA to test the hypothesis that the middle-ear muscles are activated in conjunction with other motor activities, aside from eye movements, by a central motor command system. Phi coefficients were calculated for each subject; all were positive, thus indicating an association between MEMA and other noneye movement motor events. These results suggest that there is a central phasic motor system responsible for MEMA and associated phasic motor activity in sleep.

Narcolepsy and its treatment with stimulants. ASDA standards of practice.

This review is part of the standards of practice recommendations. It has been commended and reviewed by the Board of the ASDA. It reflects recommendations of the Board for the practice of sleep medicine in North America. The subcommittee is responsible for the presented write-up.

The Sleep Disorders Questionnaire. I: Creation and multivariate structure of SDQ.

The development of the Sleep Disorders Questionnaire (SDQ) from the Sleep Questionnaire and Assessment of Wakefulness (SQAW) of Stanford University is described in detail. The extraction of the best question items from the SQAW and their subsequent rewording in the SDQ to insure greater completion rates are described. Two item test-retest reliability studies are reported on 71 controls and on 130 sleep-disorder patients, which confirmed adequate reliability. To create multivariate scoring scales, SDQ was then given in a multicenter study to 519 persons, 435 of whom were sleep-disorder patients with full polysomnography. Canonical Discriminant Function Analysis was employed, which resulted in four clinical-diagnostic scales: SA for sleep apnea, NAR for narcolepsy, PSY for psychiatric sleep disorder and PLM for periodic limb movement disorder. Each was adjusted for male and female responses and transformed to a percentile using the observed distribution of raw scores. Using Receiver Operating Characteristics analysis, cutoff points were determined for each scale to maximize its sensitivity and specificity. Positive and negative predictive values were also calculated. The SA and NAR scales proved to be the most discriminating.

Disorders of excessive daytime somnolence: polygraphic and clinical data for 100 patients.

A consecutive series of 100 sleep apnea free patients with the complaint of excessive daytime somnolence (EDS) were evaluated; data from medical histories, physical examination, personality inventories, and polysomnography [nocturnal polysomnography (NPSG) and daytime multiple sleep latency testing (MSLT)] were tabulated. Significant differences were found between narcoleptic and non-narcoleptic patients in a number of parameters, including EDS severity, mean sleep latency on MSLT, sleep latency on NPSG, latency to REM sleep at night, number of REM sleep at night, number of REM sleep segments throughout the night, the total number of nocturnal myoclonic jerks (as well as the number occurring per hour of NREM and REM sleep), and the number of arousals and wake periods preceded by a myoclonic jerk. Significant differences in sleep latency during MSLT and NPSG testing were found between different EDS diagnostic groups of non-narcoleptic patients. The majority of patients in the MSLT group with long sleep latencies were in the diagnostic groups of EDS associated with psychophysiological and/or psychiatric problems or with drug abuse; patients with a diagnosis of idiopathic central nervous system hypersomnia or EDS associated with disturbed nocturnal sleep formed the majority of the MSLT group with short sleep latencies. The non-narcoleptic patients in a MSLT group with short sleep latencies had significantly shorter sleep latencies at night, more sleep cycles, higher sleep efficiency, and earlier REM sleep than patients with long sleep latencies.

Sleep-wake disorders in the elderly: polysomnographic analysis.

The experience with 83 patients aged 60 or older from the Stanford Sleep-Wake Disorders Clinic is compared with that in 423 younger clinic patients seen during the same two-year period. Each patient received a medical, psychologic and polysomnographic evaluation. The final diagnoses were recorded according to the Diagnostic Classification System of the Association of Sleep Disorders Centers. The most common major diagnoses in the elderly group were sleep apnea syndrome (39 percent) and periodic movements-restless legs syndrome (18 percent). These syndromes showed a significantly greater prevalence in the older than in the younger patients (p less than .001), and were found in 68 percent of the elderly group. The elderly manifested more objective signs of sleep disturbance, including more wake time after sleep onset, and more frequent and longer awakenings; moreover, fewer of them experienced stage-4 sleep. The diagnostic findings seemed to indicate that complaints about sleep-wake functioning in many elderly patients may be a result of specific pathologic sleep disturbances.

Sleep patterns in borderline personality disorder.

Sleep patterns of borderline patients with and without a history of affective disorder were compared to each other and to normal reference data. The three groups could not be distinguished in terms of REM latency because a wide spread of values was seen within each group. Borderlines were different from normal controls in other aspects of sleep architecture; they had less total sleep, more stage 1 sleep, and less stage 4 sleep. If one assumes that REM latency is a biological marker for mood disorder, then our results do not support the hypothesis that borderline personality disorder is a variant of affective illness. However, other data suggest that REM latency should not be used to validate the presence of affective illness.