A New Measure of Hallucinatory States and a Discussion of REM Sleep Dreaming as a Virtual Laboratory for the Rehearsal of Embodied Cognition

Hallucinatory states are experienced not only in connection with drugs and psychopathologies but occur naturally and spontaneously across the human circadian cycle: Our nightly dreams bring multimodal experiences in the absence of adequate external stimuli. The current study proposes a new, tighter measure of these hallucinatory states: Sleep onset, REM sleep, and non‐REM sleep are shown to differ with regard to (a) motor imagery indicating interactions with a rich imaginative world, and (b) cognitive agency that could enable sleepers to recognize their hallucinatory state. Mentation reports from the different states were analysed quantitatively with regard to two grammatical–semantic constructs, motor agency and cognitive agency. The present results support earlier physiological and psychological evidence in revealing a decline in cognitive functions and an increase in simulated interactions with a hallucinatory world, en route to normal REM sleep. This leads us to introduce the hypothesis that REM sleep, which exhibits remarkably high levels of (simulated) sensorimotor processes, may have evolved to serve as a virtual laboratory for the development and rehearsal of embodied cognition. The new measure of hallucinatory states presented here may also hold implications for the study of executive functions and (meta‐)cognitions, which might be interesting, for example, for the investigation of lucid dreaming.     

Cognitive asymmetry and dreaming: lack of relationship

The present study investigated the relationship between cognitive laterality and dream recall, dream characteristics, and eye movement density in rapid eye movement (REM) sleep. Fifty-two right-handed males, age 20-30 years, were tested on a six-test battery of which three tests measure right hemisphere function and three tests measure left hemisphere function. Based on their performance, 14 subjects were selected for a sleep laboratory study. Each spent 3 experimental nights in the laboratory during which they were awakened from REM sleep for dream reports. Dream reports were scored for bizarreness, emotions, visual elements, and overall "dreamlike" versus "thoughtlike" character. Subjects were awakened from 123 REM periods, of which 96 yielded positive dream reports (78.04%). Neither the rate of recall nor the four evaluation scores were correlated with the laterality scores that were constructed from the six-test battery. Eye movement density during REM sleep was significantly positively correlated with the total performance of the two hemispheres. These results do not support the alleged lateralization of dreaming. In agreement with recent reports in the literature, it is concluded that dreaming cannot be seen as a "right hemisphere" function.     

Relation between polysomnographic measures during nocturnal sleep and a quotient of behavioral development in infants with developmental disabilities

Polysomnographic features during nocturnal sleep were investigated in 27 infants with developmental disabilities. With the use of a multiple regression analysis, 78% of the variance of a Development Quotient (DQ) measured by a questionnaire on behavioral development for infants was explained by sleep measures. Of 14 sleep measures employed in the study, (1) cumulative awakening time during a nocturnal sleep time, (2) duration of REM stage, and (3) percentage of REM to total sleep time were important in association with the DQ. The findings are consistent with the sleep-cognition hypothesis proposed by Espie, et al.     

The psychometric properties of several measures of body image

Despite the recent upsurge of interest in the construct of body image, there is relatively little information on the psychometric properties of the instruments used to measure it. This study investigated the reliability and validity of several measures of body image and compared bulimics and normals on these measures. One hundred ten normal weight females, half of whom were diagnosed as bulimic, were administered two measures of affect toward one's body, two measures of perceptions of one's entire body, and three measures of perceptions of the size of specific body sites (face, shoulders, waist, and hips). In themain, the measures provided reliable indices of body image. Examination of the correlation matrix for the measures disclosed convergence for the affective measures of body image and for all but one of the perceptual measures of body image. There was also significant covariation between the affective and the perceptual measures. The multitrait-multimethod technique was used to investigate the construct validity of the measures concerned with perceptions of the size of body sites. The multitrait-multimethod matrices disclosed substantial convergence between perceptions of face, shoulder, waist, and hip size across the three measures. However, the measure which used kinesthetic estimates of body-site size produced low reliabilities and all three of the measures showed substantial method variance. Bulimics and normals differed significantly on both the affective and the perceptual components of body image.This study is based on the first author's masters thesis. Portions of this study were represented at the 1986 meeting of the Southeastern Psychological Association. A grant to the third author from the Anclote Psychiatric Center provided support for this research project.     

Spatial and reversal learning in the Morris water maze are largely resistant to six hours of REM sleep deprivation following training

This first test of the role of REM (rapid eye movement) sleep in reversal spatial learning is also the first attempt to replicate a much cited pair of papers reporting that REM sleep deprivation impairs the consolidation of initial spatial learning in the Morris water maze. We hypothesized that REM sleep deprivation following training would impair both hippocampus-dependent spatial learning and learning a new target location within a familiar environment: reversal learning. A 6-d protocol was divided into the initial spatial learning phase (3.5 d) immediately followed by the reversal phase (2.5 d). During the 6 h following four or 12 training trials/day of initial or reversal learning phases, REM sleep was eliminated and non-REM sleep left intact using the multiple inverted flowerpot method. Contrary to our hypotheses, REM sleep deprivation during four or 12 trials/day of initial spatial or reversal learning did not affect training performance. However, some probe trial measures indicated REM sleep-deprivation-associated impairment in initial spatial learning with four trials/day and enhancement of subsequent reversal learning. In naive animals, REM sleep deprivation during normal initial spatial learning was followed by a lack of preference for the subsequent reversal platform location during the probe. Our findings contradict reports that REM sleep is essential for spatial learning in the Morris water maze and newly reveal that short periods of REM sleep deprivation do not impair concurrent reversal learning. Effects on subsequent reversal learning are consistent with the idea that REM sleep serves the consolidation of incompletely learned items.     

Adaptation of a Muslim Spiritual Attachment Scale (God attachment) for Turkish Muslims: a validity and reliability study

ABSTRACT

Despite the importance of a believer’s attachment relationship with God for mental health, there are few measures relevant to Muslims, and little work on cross-cultural validation of such measures. The objective of the present study was to examine the validity and reliability of the Muslim Spiritual Attachment Scale (M-SAS) in Turkish Muslim samples. In analyzing the data, three different samples of college students (N?=?525, N?=?341, and N?=?47 respectively) were used. The validity and reliability of M-SAS were examined through exploratory factor analysis, confirmatory factor analysis, the internal consistency coefficient and the split-half reliability coefficient. Results supported a three-factor model of M-SAS with good reliability for the factors, and convergence with an alternative God Attachment measure. As a result, it may be concluded that M-SAS can be used as a valid and reliable measurement instrument in Turkish Muslim samples. The results are discussed in the light of the relevant literature.     

Posttraining increases in REM sleep intensity implicate REM sleep in memory processing and provide a biological marker of learning potential

Posttraining rapid eye movement (REM) sleep has been reported to be important for efficient memory consolidation. The present results demonstrate increases in the intensity of REM sleep during the night of sleep following cognitive procedural/implicit task acquisition. These REM increases manifest as increases in total number of rapid eye movements (REMs) and REM densities, whereas the actual time spent in REM sleep did not change. Further, the participants with the higher intelligence (IQ) scores showed superior task acquisition scores as well as larger posttraining increases in number of REMs and REM density. No other sleep state changes were observed. None of the pretraining baseline measures of REM sleep were correlated with either measured IQ or task performance. Posttraining increases in REM sleep intensity implicate REM sleep mechanisms in further off-line memory processing, and provide a biological marker of learning potential.     

Frontal electroencephalogram alpha asymmetry during sleep: stability and its relation to affective style

Electroencephalogram (EEG) alpha (8-12 Hz) asymmetries were collected from the mid-frontal and central regions during presleep wakefulness and Stage 1, Stage 2, and rapid eye movement (REM) sleep in 11 healthy right-handed participants who were free of psychiatric, neurological, and sleep problems. The authors found significant correlations between presleep wakefulness and different stages of sleep in the frontal, but not central, EEG alpha asymmetry measure. The strongest correlation was between presleep waking and REM sleep, replicating and extending relation earlier work to a normal population. The high degree of association between presleep waking and REM sleep may be a result of high cortical activation common to these states and may reflect a predisposition to different styles of emotional reactivity.     

The case against memory consolidation in REM sleep

We present evidence disputing the hypothesis that memories are processed or consolidated in REM sleep. A review of REM deprivation (REMD) studies in animals shows these reports to be about equally divided in showing that REMD does, or does not, disrupt learning/memory. The studies supporting a relationship between REM sleep and memory have been strongly criticized for the confounding effects of very stressful REM deprivation techniques. The three major classes of antidepressant drugs, monoamine oxidase inhibitors (MAOIs), tricyclic antidepressants (TCAs), and selective serotonin reuptake inhibitors (SSRIs), profoundly suppress REM sleep. The MAOIs virtually abolish REM sleep, and the TCAs and SSRIs have been shown to produce immediate (40-85%) and sustained (30-50%) reductions in REM sleep. Despite marked suppression of REM sleep, these classes of antidepressants on the whole do not disrupt learning/memory. There have been a few reports of patients who have survived bilateral lesions of the pons with few lingering complications. Although these lesions essentially abolished REM sleep, the patients reportedly led normal lives. Recent functional imaging studies in humans have revealed patterns of brain activity in REM sleep that are consistent with dream processes but not with memory consolidation. We propose that the primary function of REM sleep is to provide periodic endogenous stimulation to the brain which serves to maintain requisite levels of central nervous system (CNS) activity throughout sleep. REM is the mechanism used by the brain to promote recovery from sleep. We believe that the cumulative evidence indicates that REM sleep serves no role in the processing or consolidation of memory.     

Field dependence and the effect of REM deprivation on thirst.

Recently a number of studies have concerned the possible function of rapid eye movement (REM) sleep and the mastery of stress. The present study was designed to explore the possibility that REM sleep might play a function in reducing the potency of a stressful physiological stimulus, thirst, as well as the possibility that such a function might be specific to individuals falling at different points along the field-dependence dimension. While there was no difference between REM deprivation and non-REM awakening nights in subsequent morning thirst, there was a significant interaction between field dependence and night on morning thirst measures for 10 college students. These results are discussed in light of previous work on stylistic differences in dreaming and their possible role in adaptation to stress.     

Hemispheric lateralization of the EEG during wakefulness and REM sleep in young healthy adults

EEG recordings confirm hemispheric lateralization of brain activity during cognitive tasks. The aim of the present study was to investigate spontaneous EEG lateralization under two conditions, waking and REM sleep. Bilateral monopolar EEG was recorded in eight participants using a 12-electrode montage, before the night (5 min eyes closed) and during REM sleep. Spectral analysis (0.75-19.75 Hz) revealed left prefrontal lateralization on total spectrum amplitude power and right occipital lateralization in Delta activity during waking. In contrast, during REM sleep, right frontal lateralization in Theta and Beta activities and right lateralization in occipital Delta activity was observed. These results suggest that spontaneous EEG activities generated during waking and REM sleep are supported in part by a common thalamo-cortical neural network (right occipital Delta dominance) while additional, possibly neuro-cognitive factors modulate waking left prefrontal dominance and REM sleep right frontal dominance.     

Use of the Sleep Assessment Device (Kelley and Lichstein, 1980) to validate insomniacs' self-report of sleep pattern

A comparison is presented of insomniacs' self-reported sleep pattern and objectively monitored sleep using the Sleep Assessment Device (SAD; Kelley & Lichstein, 1980). Analysis of 110 subject nights revealed modest but significant subjective overestimates of both sleep latency and sleep duration which were accounted for by the demands of the task (i.e., longer time periods are harder to estimate accurately). Correlations between self-report and SAD measures were, however, consistently high, suggesting that self-report may be a valid index of sleep disturbance. Results are discussed with reference to the clinician's task in evaluating sleep complaints.This research stury was supported by a grant from the Research Fund of Lanarkshire Health Board, Scotland.     

Reliability and validity of the Santa Clara Strength of Religious Faith Questionnaire

This study investigates the reliability and validity of the Santa Clara Strength of Religious Faith Questionnaire (SCSORF). The SCSORF and religiosity measures (i.e., Age Universal Religious Orientation Survey, Religious Life Inventory, and the God Control measure from the Belief in Personal Control Scale) were administered to three samples. Results suggest that the SCSORF is both reliable and valid.     

‘No Man is an Island’: Effects of social seclusion on social dream content and REM sleep

Based on the Social Simulation Theory of dreaming (SST), we studied the effects of voluntary social seclusion on dream content and sleep structure. Specifically, we studied the Compensation Hypothesis, which predicts social dream contents to increase during social seclusion, the Sociality Bias – a ratio between dream and wake interactions – and the Strengthening Hypothesis, which predicts an increase in familiar dream characters during seclusion. Additionally, we assessed changes in the proportion of REM sleep. Sleep data and dream reports from 18 participants were collected preceding (n = 94), during (n = 90) and after (n = 119) a seclusion retreat. Data were analysed using linear mixed-effects models. We failed to support the Compensation Hypothesis, with dreams evidencing fewer social interactions during seclusion. The Strengthening Hypothesis was supported, with more familiar characters present in seclusion dreams. Dream social interactions maintained the Sociality Bias even under seclusion. Additionally, REM sleep increased during seclusion, coinciding with previous literature and tentatively supporting the proposed attachment function for social REM sleep.     

Reliability conducive measures of coherence

A measure of coherence is said to be truth conducive if and only if a higher degree of coherence (as measured) results in a higher likelihood of truth. Recent impossibility results strongly indicate that there are no (non-trivial) probabilistic coherence measures that are truth conducive. Indeed, this holds even if truth conduciveness is understood in a weak ceteris paribus sense (Bovens & Hartmann, 2003, Bayesian epistemology. New York, Oxford: Oxford University Press; Olsson, 2005, Against coherence: Truth probability and justification. Oxford: Oxford University Press). This raises the problem of how coherence could nonetheless be an epistemically important property. Our proposal is that coherence may be linked in a certain way to reliability. We define a measure of coherence to be reliability conducive if and only if a higher degree of coherence (as measured) results in a higher probability that the information sources are reliable. Restricting ourselves to the most basic case, we investigate which coherence measures in the literature are reliability conducive. It turns out that, while a number of measures fail to be reliability conducive, except possibly in a trivial and uninteresting sense, Shogenji’s measure and several measures generated by Douven and Meijs’s recipe are notable exceptions to this rule.     

Social factors and the psychobiology of depression: relations between life stress and rapid eye movement sleep latency.

We examined psychosocial factors (i.e., life stress) and biological factors (i.e., REM sleep latency) that are hypothesized to be of complementary importance for defining depressive subtypes in a sample of 61 nonpsychotic, endogenous major depressives. Subjects were evaluated on several diagnostic scales for life stress, on electroencephalographic sleep data, and on 2 symptom measures for depression. As predicted, persons with severe stress that occurred shortly before depression onset had essentially normal REM latency values; patients without such stress had reduced REM latency values. Both stress and REM latency were also associated with greater severity of self-reported depressive symptoms. Alternative explanations of these findings are discussed, with particular emphasis on different roles of pre-onset and post-onset stressors.     

Reliability of the Wraparound Observation Form: An Instrument to Measure the Wraparound Process

Within the past decade, the wraparound approach has gained significant popularity in providing services to children with challenging social and family needs. While a plethora of wraparound programs have been developed and studies have been conducted to assess their effectiveness, the need to develop instruments that measure the implementation of wraparound services is clear. The purpose of the present study was to evaluate the reliability of a scale that measures wraparound services. In this study, the Wraparound Observation Form (WOF), was developed to evaluate the implementation of the wraparound process in treatment planning meetings. The WOF includes 34 closed-ended items that requires the respondent to note the occurrence or non-occurrence of specific events or behaviors at treatment planning meetings. In the present study, two data collectors attended planning meetings and independently completed the WOF. The inter-rater reliability was 95%. The WOF appears to be a reliable instrument and be appropriate in evaluating wraparound services.     

Remembering specific features of emotional events across time: The role of REM sleep and prefrontal theta oscillations

When an episode of emotional significance is encountered, it often results in the formation of a highly resistant memory representation that is easily retrieved for many succeeding years. Recent research shows that beyond generic consolidation processes, rapid eye movement (REM) sleep importantly contributes to this effect. However, the boundary conditions of consolidation processes during REM sleep, specifically whether these extend to source memory, have not been examined extensively. The current study tested the effects of putative consolidation processes emerging during REM sleep and slow wave sleep (SWS) on item and source memory of negative and neutral images, respectively. Results demonstrate superior emotional relative to neutral item memory retention after both late night REM sleep and early night SWS. Emotional source memory, on the other hand, exhibited an attenuated decline following late night REM sleep, whereas neutral source memory was selectively preserved across early night SWS. This pattern of results suggests a selective preservation of emotional source memory during REM sleep that is functionally dissociable from SWS-dependent reprocessing of neutral source memory. This was further substantiated by a neurophysiological dissociation: Postsleep emotional source memory was selectively correlated with frontal theta lateralization (REM sleep), whereas postsleep neutral item memory was correlated with SWS spindle power. As such, the present results contribute to a more comprehensive characterization of sleep-related consolidation mechanisms underlying emotional and neutral memory retention. Subsidiary analysis of emotional reactivity to previously encoded material revealed an enhancing rather than attenuating effect of late night REM sleep on emotional responses.     

Paradoxical sleep and information processing: exploration by inversion of the visual field

The purpose of this study was to test the potential relationship between REM sleep and information processing with inversion of the visual field. In the first experiment, four male subjects slept in the laboratory for two sessions of 6 consecutive nights: 2 adaptation nights, 2 nights of polysomnography, and 2 nights of dream collection. During the days preceding Nights 3, 4, 5, and 6 of each session, the subjects wore glasses which, during the second session, completely inverted (rotation of 180 degrees) their visual field. In a second experiment with four other male subjects, the order of conditions was reversed, and the experimental condition (visual inversion) was introduced a second time. When the data of the two experiments were combined, there was a significant (p less than .01) increase in the percentage of REM sleep from Nights 3 and 4 of the control condition to Nights 3 and 4 of the visual inversion condition, but there was no significant change in any of the other sleep stages. There was a significant decrease in horizontal (p less than .04) and vertical (p less than .005) REM density and in the density of vertical REM bursts (p less than .02). The increase in REM sleep supports the hypothesis that REM sleep contributes to information processing while the decrease in REM density suggests that this component of REM sleep may be involved in a homeostatic process of sensory input.     

REM need in adolescents as indicated by resistance to REM deprivation.

The hypothesis that adolescents have an exceptionally strong need for REM sleep was tested by measuring their resistance to REM deprivation. Ten adolescents (aged 16 to 17 yr.) were compared with 12 young adults (aged 25 to 27 yr.) in a standard REM deprivation procedure. The adolescents had to be awakened significantly more times than the young adults; this is consistent with the hypothesis that adolescents have a greater need for REM sleep.