Vincent P. Zarcone

Lucid Dreaming Verified by Volitional Communication during Rem Sleep

The occurrence of lucid dreaming (dreaming while being conscious that one is dreaming) has been verified for 5 selected subjects who signaled that they knew they were dreaming while continuing to dream during unequivocal REM sleep. The signals consisted of particular dream actions having observable concomitants and were performed in accordance with pre-sleep agreement. The ability of proficient lucid dreamers to signal in this manner makes possible a new approach to dream research—such subjects, while lucid, could carry out diverse dream experiments marking the exact time of particular dream events, allowing derivation of precise psychophysiological correlations and methodical testing of hypotheses.

An Actigraphic Comparison of Sleep Restriction and Sleep Hygiene Treatments for Insomnia in Older Adults

We compared the efficacy of sleep restriction therapy combined with sleep hygiene, nap modification of sleep restriction therapy combined with sleep hygiene, and sleep hygiene alone as treatments for insomnia in 39 community-dwelling men and women 55 years and older. We used the wrist actigraph as an objective outcome measure for all subjects at baseline, end of treatment, and 3-month follow-up; polysomnography (PSG) was conducted in a subgroup of subjects. Although subjects appeared to follow restriction instructions through follow-up, we found few between-group differences in treatment efficacy. Lack of treatment effect might be explained by the efficacy of HYG as a treatment in itself and the relatively low symptom level in these healthy older poor sleepers. At baseline, actigraphic results were found to correlate more highly than sleep log data with PSG in our sample. Actigraphic total sleep time, in particular, was highly correlated with PSG. (J Geriatr Psychiatry Neurol 2000; 13:17-27).

Sleep‐Wake Disorders in the Elderly: A 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 < .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.

The Validity of Self-Reported Heroin Use

During a 2-year follow-up interview, 272 male veteran heroin addicts reported their recent heroin use and provided a urine sample. Eighty-four percent of those reporting no heroin use in the 3 months preceding the interview, and 78% of those declaring no use in the previous week had urines found negative for opiates. The subjective impressions of the interviewers were useful in predicting the veracity of the self-reports. Subjects who had been in longer-term treatment, especially therapeutic communities, were more likely to report heroin use truthfully.

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 Alzheimers 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.

Plasma cortisol correlates of impulsivity and substance abuse

Abstract Biological models of impulsivity frequently propose the concept of ‘trait low arousal’ as an explanation for the sensation-seeking and rule-breaking behavior observed in such individuals. In this work, baseline activity of the hypothalamic-pituitary-adrenal (HPA) axis, as measured by plasma cortisol, was selected to test for the relationship between impulsivity and HPA-axis arousal. In addition, differences in plasma cortisol between patients with a current diagnosis of substance abuse and normal controls were sought. Fifty-three subjects (medication free averaging 10 weeks) and 20 normal controls comprised the sample assessed. Impulsivity was measured by a subscale of the Eysenck Personality Inventory. Plasma cortisol was drawn at 8:00 a.m. after an overnight fast. Results showed that the substance abusers had a significantly lower level of plasma cortisol than the controls. Moreover, within the control group cortisol was negatively correlated with impulsivity. The findings suggest that the HPA-axis may furnish a useful signal to test arousal models of personality and behavior.

All-night sleep recordings of chronic schizophrenics in remission *

Summary 1. A group of 13 chronic male schizophrenics nearing remission and 7 male control subjects were studied with all-night sleep recordings for 3 to 5 consecutive nights. 2. The patient group tended to show increased REM time, increased REM percentage, increased eye movements during REM, failure to suppress tonic EMG activity during REM, lack of the “first night effect,” and shorter REM latency periods. 3. These results and the results of other studies were discussed in relation to the hypothesis that REM sleep deprivation plays some role in the development of psychosis.

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.

CSF hypocretin-1 levels in schizophrenics and controls: relationship to sleep architecture

Hypocretins/orexins are newly identified peptides of hypothalamic origin. Hypocretin deficiency is involved in the sleep disorder narcolepsy, suggesting the importance of hypocretin neurotransmission for the regulation of sleep. Hypocretin is known to excite midbrain dopaminergic neurons and to induce hyperactivity and stereotypy in animals. Altered hypocretin neurotransmission might therefore be involved in schizophrenia, since an involvement of dopaminergic mechanisms and an association with sleep disturbance are well demonstrated in patients with schizophrenia. Hypocretin is also known to affect the hypothalamic-pituitary-adrenal axis by stimulating the release of corticotropin releasing hormone (CRH). In the current study, we measured CSF hypocretin levels in 12 controls and 13 patients with chronic schizophrenia associated with moderate sleep disturbance, such as longer sleep onset latency, decreased total sleep time and decreased sleep efficacy. No difference in CSF hypocretin levels between schizophrenia and control subjects was found. CSF hypocretin levels were positively correlated with CSF CRH levels in the patient, control and combined subject populations, but the correlation did not reach statistical significance in any population. The hypocretin levels in schizophrenic patients were, however, positively and significantly correlated with sleep latency, one of the most consistent sleep abnormalities seen in schizophrenia. This correlation was not significant in controls, and no other significant correlation between CSF hypocretin levels and any measure of sleep architecture in either patients or controls was observed. Further studies of whether CNS hypocretin neurotransmission is involved in sleep and neuroendocrine abnormalities seen in patients with schizophrenia and other psychiatric conditions are warranted.

Human sleep-electroencephalogram: A damped oscillatory phenomenon

Human sleep-electroencephalogram, obtained on a compressed time scale, very graphically demonstrates its damped oscillatory nature. Its waveform demonstrates a constant logarithmic decrement of successive peak heights and is skewed to the right. We suggest that quantitative measures may be obtained from this type of record that may help answer the following: (i) how to quantitate the biological predisposition to fall asleep at any given time, (ii) whether a particular nights sleep was normal, (iii) what length of sleep may fulfill the biological need of the subject. The rate at which the electroencephalogram of a sleeping subject is approaching maximum amplitude may be used as a measure of a force driving the phenomenon. The logarithmic decrement of successive peak heights may be used as a test for a “normal” or a “disturbed” nights sleep. The rate of decay (decay constant, k) of the envelope of electroencephalogram may be used as an index to determine the length of sleep necessary for a subject.