◆ SpookStack

252 [122] LaBERGE/LEVI WAN DEME iwreved For Release 2000/08/08 : CIA-RDP96-00789R003100140001-2 21-51; mean=28), trained in the MILD technique of lucid dream induction (see LaBerge, 1980). Subjects were selected on the basis of their claimed abil- ity to have lucid dreams on demand and were studied in a sleep laboratory for 2-25 non-consecutive nights. Standard polysomnograms (Rechtschaffen and Kales, 1968) (i.e., electroencephalogram [EEG], electro-oculogram [EOG], and chin electromyogram [EMG)]) were recorded, as well as, in certain cases, a variety of additional physiological measures. Before bedtime on recording nights subjects were instructed to immediately signal whenever they realized they were dreaming. A variety of signals were specified, typically two pairs of extreme horizontal eye-movements (left, right, i j eived additional instructions to carry OF LUCID DREAMING 253 [123] . (HR) and respiration rate (RR) were also determined for SVLDs recorded with the relevant measures. For the first lucid epoch (during signals), STATE was unequivocal REM in 70 cases (92%). The remaining six SVLDs were less than 30” long and hence technically unscorable by the orthodox (Rechtshaffen and Kales, 1968) criteria. For these cases, the entire SVLD was treated as a single epoch and scored as if they were of standard length; with this modification, all qualified as REM. The lucid dream signals were followed by an average of 115 seconds (range: 5 to 490 seconds) of uninterrupted REM sleep. Anecodotal reports indicate that lucid dreams are sometimes initiated from out specific activities in the dream state once they became lucid. In the course of the study, 88 lucid dreams were reported subsequent to spontaneous awakenings from the following stages of sleep, scored according to the standard criteria (Rechtschaffen and Kales, 1968): REM in 83 cases (94.3%), NREM Stage-1 in four cases (4.5%), and at the transition between NREM Stage-2 and REM in one case (1.1%). The subjects reported signaling in 80 cases (90.9%), all following REM awakenings (96.4% of the REM reports). After each recording, reported lucid dream signals were verified by means of a blind judging procedure previously detailed elsewhere (LaBerge et al., 1981). Briefly, the reports mentioning lucidity signals were submitted along with the respective polysomnograms to a judge who attempted to determine which 30" epoch of the physiological records corresponded to a given reported signal. The judge (blind to the times the reports were made) successfully matched 76 (95%) of the reported signals to an epoch from the correct REM period. The probability that such a large number of matches could have been made by chance is infinitesmally small. The 13 subjects contributed varying numbers of signal-validated lucid dreams (SVLDs) ranging from 1-25, each with the median number of SVLDs per subject being four. Although four subjects furnished a single SVLD each while another two subjects together supplied 43 (56% of the total), the number of SVLDs contributed by the two sexes did not significantly differ. Potential problems arising from the unequal N of observations per subject were averted by statistically analysing summary scores for all physiological variables (i.e., the mean of each subject’s mean values, yielding a maximum N=13). The polysomnograms corresponding to each of the SVLDs were sleep- staged. Additionally, every SVLD REM period was divided into 30 second epochs aligned with the lucidity onset signal; up to 60 epochs of data from the preceding (non-lucid) REM period and 15 epochs from the lucid dream were collected. For each epoch, sleep stage (STATE) was scored and rapid eye movements (EM) were counted; if scalp skin-potential responses were observable as artifacts in the EEG, these were also counted (SP). Heart rate the-waking-state, but moretrequently_from-the-dream-state (Green, 1968; LaBerge, 1985a). Since lucid dreams initiated in these two ways would be ex- pected to differ physiologically, SVLDs were dichotomously classified as either “Wake-initiated” (WILD) or “Dream-initiated” (DILD), depending on whether or not the reports mentioned a transient awakening (i-e., conscious percep- tion of the external environment). Fifty-five (72%) of the SVLDs were classified as DILDs and che remaining 21 (28%) as WILDs. For all 13 subjects, DILDs were more common than WILDs (binomial test, p<.0001). Compared to DILDs, WILDs were more frequently immediately preceded by physiological indications of arousal (y?=38.3, Idf, p<.0001), establishing the construct valid- ity of the classification dimension. Figure 1 illustrates a typical DILD. Four channels of physiological data (cen- " tral EEG [C,-A,], left and right eye-movements [LOC and ROC], and chin muscle tone [EMG]) from the last 8 minutes of a 30 minute REM period are shown. Upon awakening the subject reported having made five eye move- ment (EM) signals (labeled 1-5). The first signal (1, two pairs of left-right EMs) marked the onset of lucidity. During the following 90 seconds the subject “flew about” exploring his dream world until he believed he had awakened, at which point he made the signal for awakening (2, four pairs of left-right EMs). After another 90 seconds the subject realized he was still dreaming and signaled (3) with three pairs of EMs. Realizing that this was too many, he correctly signaled with two pairs (4). Finally, upon awakening two minutes later he signaled appropriately (5, four pairs of EMs). Figure 2 illustrates six channels of physiology (left and right temporal EEG [T3 and T4}, left and right eye-movements [LOC and ROC], chin muscle tone [EMG], and electrocardiogram [ECG)) for a typical WILD. The subject awoke at | and after 40 seconds returned to REM sleep at 2, and realized he was dreaming 15 seconds later at 3. Next he carried out the agreed-upon dream actions, singing between signals 3 and 4, and counting between signals 4 and 5. This allowed comparison of left and right hemisphere activation dur- ing the two tasks (LaBerge and Dement, 1982a). Physiological comparison of lucid versus non-lucid epochs revealed that lucid Approved For Release 2000/08/08 : CIA-RDP96-00789R003100140001-2