This article was downloaded by: [University North Carolina - Chapel Hill] On: 01 December 2014, At: 11:12 Publisher: Routledge Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK
Journal of Sex & Marital Therapy Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/usmt20
Women's vaginal responses during REM sleep a
b
Gene G. Abel MD , William D. Murphy PhD , Judith V. Becker PhD & Adib Bitar MD
c
a
Department of Psychiatry , College of Physicians and Surgeons, Columbia University , New York, N.Y. b
Department of Psychiatry , University of Tennessee , Memphis
c
University of Southern California , L.A. Published online: 14 Jan 2008.
To cite this article: Gene G. Abel MD , William D. Murphy PhD , Judith V. Becker PhD & Adib Bitar MD (1979) Women's vaginal responses during REM sleep, Journal of Sex & Marital Therapy, 5:1, 5-14, DOI: 10.1080/00926237908403713 To link to this article: http://dx.doi.org/10.1080/00926237908403713
PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http://www.tandfonline.com/page/termsand-conditions
a
Journal of Sex It Marital 'Therapy Vol. 5. N o . 1, Spring 197'3
Women's Vaginal Responses During REM Sleep Downloaded by [University North Carolina - Chapel Hill] at 11:12 01 December 2014
Gene G . Abel, MD, William D . Murphy, PhD, Judith V . Becker, PhD, and Adib B itar, MD
ABSTRACT: Eight female subjects underwent vaginal photoplethysmographic recordings while asleep. Results demonstrated consistent findings of decreases in relative blood volume and increases in relative pulse pressure within the vagina during REM periods. These vascular changes indicate that females undergo phasic shifts in vascular blood flow in the vagina d u r i n g REM sleep, similar to the phasic shifts of blood flow in the male's penis d u r i n g REM sleep.
Major advances have been made recently in the physiological measurement of sexual arousal in males, allowing a more objective means of studying the male sexual response. Of the numerous physiologic measures possible, Zuckerman' indicates that direct measurement of penile tumescence is the most reliable and valid. This measurement procedure has been used primarily to quantify sexual arousal in sexual deviates and monitor treatment effectiveness in this Another application of this measurement of special relevance to therapists in the area of sexual dysfunction is the use of nocturnal erection measures during rapid eye movement (REM) sleep to differentiate psychogenic impotence from organic impotence. T h e clinical value of this method has received initial support 69'*8 because it provides a more direct means of separating these two diagnostic categories* l 2 and cannot be distorted by the patient's self-report. Dr. Abel. Research Psychiatrist, and Dr. Becker, Assistant Professor of Psychology, are with the Department of Psychiatry, College of Physicians and Surgeons, Columbia University (New York, N.Y.); Dr. Murphy is Assistant Professor of Psychology, Department of Psychiatry, University of Tennessee (Memphis); and Dr. Bitar is Assistant Professor of Psychiatry, University of Southern California (LA.). Requests for reprints should be sent to Dr. Gene G. Abel, Department of Psychiatry, College of Physicians and Surgeons, Columbia University, 722 West 168th Street, New York, N.Y. 10032. The authors wish to acknowledge the assistance of Emily Coleman in the conduction of these studies and Peter Hoon, PhD, in preparation of the manuscript. Portions of this research were supported by USPHS Grant AM-20844.
5 0092-623X/7911300-0005$00.95
@ 1979 Human Sciences Press
Journul q J Sex and Maiitul Therupy
Downloaded by [University North Carolina - Chapel Hill] at 11:12 01 December 2014
6
I n contrast, similar diagnostic procedures are almost nonexistent for females. This is due, in part, to a lack of technology for the objective measurement of sexual arousal in females until very recently. A vaginal photoplethysmograph system has now been developed 1 3 * 1 4 that provides a reliable, valid measure of female sexual a r o ~ s a l . ' ~ - ' ~ Since REM erection measures have furthered our understanding of male sexual physiology and provided a valuable diagnostic aide in separating psychogenic from organic impotence, it seems appropriate to attempt REM vaginal measures in females to determine if phasic vascular changes occur in females as well as males. If present, further investigation may provide the means of separating psychogenic sexual dysfunction problems from organically caused problems in the female. Although the recording of women's vaginal responses during sleep might have significant clinical relevance, a review of the literature revealed only three articles (all published in abstract form) that dealt with this issue. Cohen and Shapiro'!' and Shapiro, Cohen, DiBianco, and Rosenz0report increases in vaginal blood flow in three females during REM sleep. They used an isothermal relative vaginal blood flow device, but no actual data were reported. A second device similar to that used to record penile size2' recorded clitoral engorgement during REM sleep in two females with congenital clitoral enlargement. These three studies suggest that perineal engorgement does occur in females during REM sleep. This report extends the limited data and delineates the parameters of nocturnal sexual responding in normal females using the vaginal photoplethysmograph. This measurement device has greater utility and applicability than that used to measure the congenitally enlarged clitoris and has more validity data associated with it than the isothermal blood flow device. In addition, a larger sample size is included in this report.
METHOD
Subjects Eight females, ages 23 to 35 were recruited from nursing staff and from acquaintances of the researchers. Requirements for the experiment were that the subjects reported being orgasmic and agreed to sign thc informed consent form describing this experimental procedure. All subjccts were paid $25 for two nights of sleep recording. N o subject was run during their menstrual period, if they reported an active vaginal infection o r any vaginal anomaly that would preclude insertion of the vaginal photophlethysmograph. In addition, subjects were required to have had a pelvic examination within a 6-month period prior to the study.
Apparatus All physiological measurements were made with a Grass Model-7 polygraph, equipped with appropriate preamplifiers. To assist in defining REM periods the electromyograph
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Gene G.Abel, MD,et d.
7
(EMG) was recorded from the frontalis muscle via a Grass 7P3 preamplifier while the electrooculograph (EOG) was recorded between the outer canthi of each eye via a Grass 7P 1 preamplifier. Blood changes in the vagina were recorded using a reflective photoplethysmographic system similar to that described by Sintchak and Geer.I4 In brief, the system consisted of a photocell and light source enclosed in a clear acrylic cylinder approximately 1.3 cm in diameter and 4.5 cm in length, attached to a bridge circuit. Both the DC component (relative blood volume) and the AC component (relative pulse pressure) were recorded. Blood volume was recorded through a Grass 7P 1 preamplifier with the sensitivity level set on .2 mvlcm. Initial calibration of this DC signal was made by placing the vaginal photoplethysmograph in each of two boxes (10 cm x 10 cm x 10 cm) lined with materials differing in optical reflectance. For calibration purposes the 7P1 preamplifier sensitivity was set at 5 mv/cm, the vaginal photoplethysmograph was placed in a high reflectance box (90% reflective), and the baseline was set in the middle of the channel using the balance voltage controls of the 7P1. Next the photoplethysmograph was moved to a low reflectance box (18% reflective) and the sensitivity of the 7P1 was adjusted to provide a pen deflection of' 2 cm. For recording purposes the sensitivity was then returned to .2 mvkm. T h e AC component of' the photoplethysmograph (relative pulse pressure) was recorded via a Grass 7P3 AC preamplifier with a sensitivity of I mvkm and a time constant of .08 seconds. For data purposes the raw relative pulse pressure (PP, signal was averaged through the integration circuit (time constant set at .05) of' the 7P3 preamplitier and displayed on a separate channel of the polygraph. T h e %-amp-high-frequency switch of the driver amplifier associated with the averaged pulse pressure was set at .5 Hz to smooth the incoming signal. In addition, this averaged pulse pressure was passed through the Grass 7P10 cumulative integrator, which provided a cumulative value for the pulse pressure each minute. However, this derived measure produced data identical to the averaged pulse pressure and, therefore, will not be reported here. All recording equipment was housed in a separate room adjacent to the room in which the subject slept. Verbal communication was provided through an intercom system, and no visual communication was possible.
Procedure Prior to the night recording, all subjects were interviewed, the procedures involved in the night recordings were explained, and subjects were asked to sign informed consent forms. All subjects were also given a series of sexual questionnaires to complete at their convenience prior to their actual night recordings. These are part of our ongoing research and are not presented here. For the sleep recordings, subjects reported to the laboratory at approximately 10:OO pm. At this time the experimenter explained in detail the insertion of the vaginal probe and the attachment of the EMG and EOG electrodes. Subjects were instructed to insert the probe as they would a tampon but only into the outer third of the vagina (where vascularization is greatest during sexual arousal). T h e experimenter then left the room while the subject dressed for bed and inserted the probe. Once the subject was in bed, shc called thc experimenter over the intercotn, who then returned, attached the EMG and EOG electrodes, and gave any final instructions. After these instructions the experimenter returned to the equipment room, and once the vaginal measures had stabilized (usually 15 to 20 minutes after probe insertion), the experimenter instructed the subject to have a sexual fantasy. The fantasy lasted until the subject reported she could no longer hold the fantasy or for 5 minutes, whichever came first. Following the fantasy, the subject was asked to provide subjective ratings of the degree of sexual arousal and pleasure produced by the fantasy, plus the clarity of the imagery. Once the measures had again stabilized, the subject was asked to have a second sexual fantasy. Initially, we had planned on comparing the sexual arousal associated with the fantasies with the sexual arousal during REM sleep, similar to the procedure of Cohen
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8
Journal of Sex and Marital Therupy
and Shapiro.'% However, the large variability between subjects' data during the fantasies as compared to the relatively small variability between subjects' data associated with the REM responses precluded any meaningful comparison. Following the second fantasy, subjects were told they could go to sleep. Either one of the experimenters or a technician monitored the record throughout the night, labeling on the record any movement artifact or any time the subjects reported being awake during the night. In the morning when the subject awoke, the experimenter entered the room, removed the electrodes, and left so the subject could remove the photoplethysrnograph. Between recording nights the vaginal probe was sterilized in Zephiran Chloride ( I to 750 dilution) and rinsed in water. T h e procedures for the second night of recording were identical to those used during the first night. 'Time between recordings ranged from the next night t o one week.
Quantifzcation of data. To determine REM periods, the polygraph was visually inspected and REM periods were defined by increases in EOG activity with concommitant decreases in EMG activity. Because of equipment limitation, an EEG was not available, which at times complicated a clear determination of REM periods. However, a conservative approach was taken, and any questionable REM periods were not included, even though they were associated with typical changes in the vaginal recordings. Once the REM period was det.ermined, the following data were scored for that period: (1) maximum relative blood volume in mm of pen deflection from the middle of the polygraph channel, (2) minimum blood volume in mm of pen deflection from the middle of the polygraph channel, and (3) maximum averaged pulse pressure from the 7P3 integrator scored in mm of pen deflection from the bottom of the polygraph channel. For comparison purposes a pre-REM period was established by sampling a 2-minute interval beginning 4 minutes prior to the onset of each REM period. This pre-REM period was scored as above for the same three dependent variables. Data were excluded that were accompanied by movement artifact detected on the basis of either polygraph recordings o r subject-produced movement sounds heard over the intercom. Data to he presented include the three vaginal measures during REM sleep periods for the one night of clearest recording. Only one night of dat:a is reported because, i n some instances, excessive artifact due to problems sleeping o r equipment difficulties preclude the use of data from the other night's recording.
RESULTS Figures 1 through 3 reflect the results of a typical subject during the various instructions and during sleep. Figure 1 shows the EOG, EMG, the three measures of relative pulse pressure (cumulative, averaged, and A.C. pulse amplitudes), and the D.C. relative blood volume during no instructions (pre-fantasy) and instructions to have a sexual fantasy (fantasy). While awake and reporting a sexual fantasy, the subject's A.C. pulse amplitude and D.C. blood volume both increase. Figure 2 shows the same subject's physiologic measures during a preREM period with minimal EOG activity, high EMG activity, and baseline D.C. and A.C. measures. With the onset of REM sleep (Figure 3) EOG activity increases, the EMG amplitude decreases, and there is both a marked increase in pulse amplitude and a concomitant, dramatic decrease in blood volume.
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Gene G.Abel, MD. el al.
4,
FIGURE 1: EOG, EMG, A.C., and D.C. Vaginal Pulse Amplitudes Before and D u r ing Sexual Fantasies.
A summary of all REM periods for all subjects is presented in Table 1, which indicates change scores for each subject from pre-REM baselines including maximum relative blood volume‘(MAX-BV), minimal relative blood volume (MIN-BV), and maximum averaged relative pulse pressure (MAX-PP). Table 1 is a summary of individual subject data for the largest response of the night based on each subject’s MAX-PP (left-hand columns) and the means for all REM periods observed in each subject during a single night (right-hand columns). From Table 1, a typical vaginal response pattern can be observed with a drop in MIN-BV and a concomitant increase in the MAX-PP measures. This pattern is observed for all eight subjects and is the same whether the maximum response of the night is inspected or the mean values are taken for all REM periods during the night. T h e MAX-BV score is less consistent with a slight overall increase in MAX-BV during REM when the means of all the REM periods are inspected. T h e conclusions from visual inspection of the data are supported statistically when correlated t-tests22are applied to the data. For the maximum response of the night (left-hand columns of Table 1) this analysis indicates no significant difference between the pre-REM periods and REM
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Journal of Sex and Murital Therapy
FIGURE 2: LOG, EMG, A.C., and D.C. Vaginal Pulse Amplitudes during Non-KEM Sleep.
periods for MAX-BV (t = 1.47, df = 7, n.s.); a significant increase in the MAX-PP ( t = 10.55, df = 7 , p < .001) over the pre-REM period; and a significant decrease in MIN-BV ( t = 7.70. df = 7, p < ,001). When the mean values (right-hand columns of Table 1) were analyzed with the same statistical procedure, the results were similar to the analysis of MIN-BV and MAX-PP (with p < -001) during the MAX-REM period. However, in this second analysis, the increase in MAX-BV ( t = -3.48,df = 7,p < .02), indicated a significant increase in blood volume over the pre-REM period for the mean values during REM. It should be noted that the MIN-BV changes are somewhat smaller than what actually occurred because in four of the REM periods (two of which are represented in the MAX-REM periods in Table 1) the recording pen dropped off channel. When this occurred, the value recorded was the mm of pen deflection at the point the pen dropped off channel, which is an underestimation of what the true value would have been if the total drop in BV could have been recorded.
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Gene G . Abel, MD, et al.
11
FIGURE 3: EOG, EMG, A.C., and D.C. Vaginal Pulse Amplitudes During REM Sleep.
The data for the means of all REM periods for each subject and the MAX-REM response of the night indicate a high degree of consistency. To further investigate this consistency, all 31 REM periods observed across all subjects were inspected. A frequency count was taken for all periods where the MAX-BV, MIN-BV, and MAX-PP showed a change of 10 mm or more from the pre-REM period. Results from this analysis indicate that for MAX-BV an increase of 10 or greater was found in only 9/3 1 of the REM periods, while for MIN-BV a decrease of 10 or more was found in 2613 1 of the REM periods. For the MAX-PP an increase of 10 or greater occurred in 19/31 of the REM periods. It was also observed that in none of the 31 REM periods was the MAX-PP measure less than that observed in the pre-REM periods nor was the drop in BV less than or equal to drops observed in pre-REM periods. However in 6/31 periods the value observed for MAX-BV was less than or equal to that observed in the pre-REM periods, suggesting again that MAX-BV increases are an inconsistent finding during REM periods.
Journal of Sex and Marital Therapy
12
I
W. REM PERIOD
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8
MEAN
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DISCUSSION
These results indicate that normal females have a specific vaginal response pattern during sleep. Females show periodic increases in relative pulse pressure and, contrary to our expectations, a concomitant decrease in relative blood volume during REM sleep. In some instances there is a biphasic response in BV; however, the increase in BV observed during REM is small and not as dramatic as the decrease in BV or the increase in PP. The increased BV may be a reflection of the scoring system used. Until further data are collected, the vaginal responses of females during sleep are most reliably described as a decrease in BV associated with an increased in PP. Within the limitations of the physiological measures obtained, these phasic changes appear to occur during REM sleep similar to the nocturnal REM erection observed in male^.^,',^ Cohen and Shapirol9 and Shapiro, Cohen, DiBianco, and Rosen,20 have shown increases in blood flow to the vagina during sleep in females using an isothermal measurement device. These studies are consistent with the increases in pulse pressure observed in the present investigation since pulse pressure has been found to correlate with blood f10w.23*24In
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Gene G . Abel. MD,et al.
13
contrast, it would appear that the blood volume measure obtained from the walls of the vagina is inconsistent with the data reported by Karacan et aL8 They found increased engorgement of the clitoris while recording from females with congenitally enlarged clitorises. It is possible that during REM sleep the vascular response of the clitoris is different physiologically from the vascular response of the walls of the vagina or that the physiologic abnormalities of the subjects measured by Karacan led to results different from the normal females used in this study. Further research is necessary to explore the discrepancies in these studies. The decrease in blood volume during REM sleep was unexpected, given the results of Masters and Johnson,25which suggest that during the waking state, female sexual arousal is accompanied by vasocongestion. In addition, photoplethysmographic studies demonstrate increases in blood volume and pulse pressure during sexual a r o u ~ a l . ’ ~ ” ~However, ”* if the photoplethysmographic response is recorded during orgasm rather than the early excitement phase, a pattern is observed very similar to the sleep records of the present study. Geer and Q ~ a r t a r a r o ’reported ~ photoplethysmographic records of seven females during masturbation. In each case a decrease in BV was observed when orgasm was reported. Because of artifact, the PP measure could not be observed during six of the seven orgasms. However, there was an increase in PP during masturbation, which was maintained during the resolution phase following orgasm. In the one case where PP could be interpreted, an increase was observed during orgasm while the BV decreased concomitantly, similar to the present sleep data. It is possible that the pattern of results in this sleep study are similar to the orgasmic phase of sexual arousal rather than the excitement or plateau phase.25 Although speculative, this hypothesis does seem to warrant further investigation. The major criticism of the present study is the failure to include an EEG measurement to assist in defining REM periods. However, the scoring of the data was conservative, leading to the exclusion of some of the largest vaginal responses of the night, even though these responses followed the exact pattern of the data presented. Secondly, the measures that were obtained (EMG and EOG) are consistently associated with REM sleep. EMG decreases seem especially indicative of REM sleepz6and was one of the variables used to define REM in the present study. Whether the pattern of vaginal responses observed in this study occurred during REM or non-REM periods may not be critical should the presence or absence of these responses be found to be of diagnostic value in separating the organic from psychogenic causes of sexual dysfunctions in females. Currently, the phasic erections observed in males do not depend on their being coincident with REM periods to assist in the differential diagnosis of sexual dysfunctions. Instead, it is the absolute size
14
Journal o j Sex und Marital Therupy
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of erection that the male gets during sleep that allows impotence to be categorized as psychogenic or organic in etiology. Only further studies measuring the sexual responses of dysfunctional women during REM will determine if vaginal photoplefhysmographic measures will separate the psychogenic from the organic sexual dysfunctions of women.
REFERENCES 1. Zuckerman M: Physiological measures of sexual arousal in the human. PsycholBull75: 297-329,
1971. 2 . Abel GG: Recent research on the evaluation and treatment of the rapist. In M Walkcr (Ed), Rape: Research, Acfion, Prevention. Proceedings of the Sixth Alabama Symposium on Justice and the Behavioral Sciences, Tuscaloosa, 1975. 3 . Abel GG: Assessment of Sexual deviation in the male. In M Hersen, AS Bellack (Eds). Behavioral Assessment: A Practical Handbook. New York, Pergamon, 1976, p 437. 4 . Abel GG, Blanchard EB: T h e measurement and generation of sexual arousal in male sexual deviates. In M Hersen, R Eider, PM Miller (lids), Progress in Behavior Modijication, Vol 2. New York, Academic Press. 1976, p 99. 5. Freund K: Laboratory differential diagnosis of homo- and heterosexuality: An experiment with faking. Rev Crrch Mtd 7:20-3 I , 196 1. 6. Fisher C, Schiavi R, Lear H , e t al: T h e assessment of nocturnal REM erection in the differential diagnosis of sexual impotence. J Sex Marital Ther lr277-289, 1975. 7 . Karacan I : Clinical value of nocturnal erection in the prognosis and diagnosis of impotence. Med Aspects Hum Sex 4:27-34, 1970. 8. Karacan I, Williams RI., ‘I’hornby JI. Salk PJ: Sleep-related penile tumescence as a function of age. A m J Psychiatry 132:932-937, 1975. 9. Abelson D: Diagnostir value of the penile pulse and blood pressure: A doppler study of impotence in diabetics. J Ur01113:636-639, 1975. 10. Britt DR, Kcmmerer WI’, Robison JR: Penile blood flow determination by mercury strain gauge plethysmography. Inue.$t Urol8:673-678, 1971. 1 1 . Ellenberg M : Impotence in diabetes: T h e neurologic factor. Ann Intern Med 75:213-219, 1971. 12. Ellenberg M, Weber H : T h e incipient asymtomatic diabetic bladder. Diabetes 16:331-339, 1967. 13. Ceer J , Morokoff P, Greenwood P: Sexual arousal in women: T h e development of a measurement device for vaginal blood volume. Arch Sex B t h v ?:559-564, 1974. 14. Sintchak G,Geer J: A vaginal photoplethysmograph system. Psychophysiology 12: 113-1 15, 1975. 1.5. Geer J H , Quartararo JD: Vaginal blood volume responses during masturbation. Arch Sex Behau 5:403-413, 1976. 16. Heiman JR: T h e physiology of erotica: Women’s sexual arousal. Psycho1 Today, April 1975,91-94. 17. Hciman JR: A psychophysiological exploration of sexual arousal patterns in females and males. Psychophysiology 14:266-274, 1977. 18. Hoon PW, Wincze JP, Hoon EF: Physiological assessment of sexual arousal in women. Psychophysiology 13: 196-204, 1976. 19. Cohen HD, Shapiro A: Vaginal blood flow during sleep. Psychophysiology 7:338, 1970. 20. Shapiro A, Cohen H, DiBianco P, Rosen G: Vaginal blood flow changes during sleep and sexual arousal. Psychophysiology 4:394, 1972. 21. Karacan I , Rosenbloom AL, Williams KL: T h e clitoral erection cycle during sleep. Psychophysiology 7:338, 1970. 22. Bruning JL, Kin12 BL: Computational Handbook of Statistics. Glenview, Ill, ScotdForesman, 1968. 23. Burton AC: T h e range and variability of the blood flow in the human fingers and vasomotor regulation of body temperature. Am J Physiol 127:437-453, 1939. 24. Hertzman AB, Randall WC, ]ochim KE: The estimation of the cutaneous blood flow with the photoelectric plethysmograph. A m J Physiol 145:716-726, 1946. 25. Masters WH,Johnson VE: Human Sexual Response. Boston, Little Brown, 1966. 26. Bliwise D, Coleman R, Bergman B, Wincor RT, Pivik RT, Rechtschaffen A: Facial muscle tonus during REM and NREM sleep. Psychophysiology 11:497-508, 1974.
Journal of Sex & Marital Therapy Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/usmt20
Women's vaginal responses during REM sleep a
b
Gene G. Abel MD , William D. Murphy PhD , Judith V. Becker PhD & Adib Bitar MD
c
a
Department of Psychiatry , College of Physicians and Surgeons, Columbia University , New York, N.Y. b
Department of Psychiatry , University of Tennessee , Memphis
c
University of Southern California , L.A. Published online: 14 Jan 2008.
To cite this article: Gene G. Abel MD , William D. Murphy PhD , Judith V. Becker PhD & Adib Bitar MD (1979) Women's vaginal responses during REM sleep, Journal of Sex & Marital Therapy, 5:1, 5-14, DOI: 10.1080/00926237908403713 To link to this article: http://dx.doi.org/10.1080/00926237908403713
PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http://www.tandfonline.com/page/termsand-conditions
a
Journal of Sex It Marital 'Therapy Vol. 5. N o . 1, Spring 197'3
Women's Vaginal Responses During REM Sleep Downloaded by [University North Carolina - Chapel Hill] at 11:12 01 December 2014
Gene G . Abel, MD, William D . Murphy, PhD, Judith V . Becker, PhD, and Adib B itar, MD
ABSTRACT: Eight female subjects underwent vaginal photoplethysmographic recordings while asleep. Results demonstrated consistent findings of decreases in relative blood volume and increases in relative pulse pressure within the vagina during REM periods. These vascular changes indicate that females undergo phasic shifts in vascular blood flow in the vagina d u r i n g REM sleep, similar to the phasic shifts of blood flow in the male's penis d u r i n g REM sleep.
Major advances have been made recently in the physiological measurement of sexual arousal in males, allowing a more objective means of studying the male sexual response. Of the numerous physiologic measures possible, Zuckerman' indicates that direct measurement of penile tumescence is the most reliable and valid. This measurement procedure has been used primarily to quantify sexual arousal in sexual deviates and monitor treatment effectiveness in this Another application of this measurement of special relevance to therapists in the area of sexual dysfunction is the use of nocturnal erection measures during rapid eye movement (REM) sleep to differentiate psychogenic impotence from organic impotence. T h e clinical value of this method has received initial support 69'*8 because it provides a more direct means of separating these two diagnostic categories* l 2 and cannot be distorted by the patient's self-report. Dr. Abel. Research Psychiatrist, and Dr. Becker, Assistant Professor of Psychology, are with the Department of Psychiatry, College of Physicians and Surgeons, Columbia University (New York, N.Y.); Dr. Murphy is Assistant Professor of Psychology, Department of Psychiatry, University of Tennessee (Memphis); and Dr. Bitar is Assistant Professor of Psychiatry, University of Southern California (LA.). Requests for reprints should be sent to Dr. Gene G. Abel, Department of Psychiatry, College of Physicians and Surgeons, Columbia University, 722 West 168th Street, New York, N.Y. 10032. The authors wish to acknowledge the assistance of Emily Coleman in the conduction of these studies and Peter Hoon, PhD, in preparation of the manuscript. Portions of this research were supported by USPHS Grant AM-20844.
5 0092-623X/7911300-0005$00.95
@ 1979 Human Sciences Press
Journul q J Sex and Maiitul Therupy
Downloaded by [University North Carolina - Chapel Hill] at 11:12 01 December 2014
6
I n contrast, similar diagnostic procedures are almost nonexistent for females. This is due, in part, to a lack of technology for the objective measurement of sexual arousal in females until very recently. A vaginal photoplethysmograph system has now been developed 1 3 * 1 4 that provides a reliable, valid measure of female sexual a r o ~ s a l . ' ~ - ' ~ Since REM erection measures have furthered our understanding of male sexual physiology and provided a valuable diagnostic aide in separating psychogenic from organic impotence, it seems appropriate to attempt REM vaginal measures in females to determine if phasic vascular changes occur in females as well as males. If present, further investigation may provide the means of separating psychogenic sexual dysfunction problems from organically caused problems in the female. Although the recording of women's vaginal responses during sleep might have significant clinical relevance, a review of the literature revealed only three articles (all published in abstract form) that dealt with this issue. Cohen and Shapiro'!' and Shapiro, Cohen, DiBianco, and Rosenz0report increases in vaginal blood flow in three females during REM sleep. They used an isothermal relative vaginal blood flow device, but no actual data were reported. A second device similar to that used to record penile size2' recorded clitoral engorgement during REM sleep in two females with congenital clitoral enlargement. These three studies suggest that perineal engorgement does occur in females during REM sleep. This report extends the limited data and delineates the parameters of nocturnal sexual responding in normal females using the vaginal photoplethysmograph. This measurement device has greater utility and applicability than that used to measure the congenitally enlarged clitoris and has more validity data associated with it than the isothermal blood flow device. In addition, a larger sample size is included in this report.
METHOD
Subjects Eight females, ages 23 to 35 were recruited from nursing staff and from acquaintances of the researchers. Requirements for the experiment were that the subjects reported being orgasmic and agreed to sign thc informed consent form describing this experimental procedure. All subjccts were paid $25 for two nights of sleep recording. N o subject was run during their menstrual period, if they reported an active vaginal infection o r any vaginal anomaly that would preclude insertion of the vaginal photophlethysmograph. In addition, subjects were required to have had a pelvic examination within a 6-month period prior to the study.
Apparatus All physiological measurements were made with a Grass Model-7 polygraph, equipped with appropriate preamplifiers. To assist in defining REM periods the electromyograph
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(EMG) was recorded from the frontalis muscle via a Grass 7P3 preamplifier while the electrooculograph (EOG) was recorded between the outer canthi of each eye via a Grass 7P 1 preamplifier. Blood changes in the vagina were recorded using a reflective photoplethysmographic system similar to that described by Sintchak and Geer.I4 In brief, the system consisted of a photocell and light source enclosed in a clear acrylic cylinder approximately 1.3 cm in diameter and 4.5 cm in length, attached to a bridge circuit. Both the DC component (relative blood volume) and the AC component (relative pulse pressure) were recorded. Blood volume was recorded through a Grass 7P 1 preamplifier with the sensitivity level set on .2 mvlcm. Initial calibration of this DC signal was made by placing the vaginal photoplethysmograph in each of two boxes (10 cm x 10 cm x 10 cm) lined with materials differing in optical reflectance. For calibration purposes the 7P1 preamplifier sensitivity was set at 5 mv/cm, the vaginal photoplethysmograph was placed in a high reflectance box (90% reflective), and the baseline was set in the middle of the channel using the balance voltage controls of the 7P1. Next the photoplethysmograph was moved to a low reflectance box (18% reflective) and the sensitivity of the 7P1 was adjusted to provide a pen deflection of' 2 cm. For recording purposes the sensitivity was then returned to .2 mvkm. T h e AC component of' the photoplethysmograph (relative pulse pressure) was recorded via a Grass 7P3 AC preamplifier with a sensitivity of I mvkm and a time constant of .08 seconds. For data purposes the raw relative pulse pressure (PP, signal was averaged through the integration circuit (time constant set at .05) of' the 7P3 preamplitier and displayed on a separate channel of the polygraph. T h e %-amp-high-frequency switch of the driver amplifier associated with the averaged pulse pressure was set at .5 Hz to smooth the incoming signal. In addition, this averaged pulse pressure was passed through the Grass 7P10 cumulative integrator, which provided a cumulative value for the pulse pressure each minute. However, this derived measure produced data identical to the averaged pulse pressure and, therefore, will not be reported here. All recording equipment was housed in a separate room adjacent to the room in which the subject slept. Verbal communication was provided through an intercom system, and no visual communication was possible.
Procedure Prior to the night recording, all subjects were interviewed, the procedures involved in the night recordings were explained, and subjects were asked to sign informed consent forms. All subjects were also given a series of sexual questionnaires to complete at their convenience prior to their actual night recordings. These are part of our ongoing research and are not presented here. For the sleep recordings, subjects reported to the laboratory at approximately 10:OO pm. At this time the experimenter explained in detail the insertion of the vaginal probe and the attachment of the EMG and EOG electrodes. Subjects were instructed to insert the probe as they would a tampon but only into the outer third of the vagina (where vascularization is greatest during sexual arousal). T h e experimenter then left the room while the subject dressed for bed and inserted the probe. Once the subject was in bed, shc called thc experimenter over the intercotn, who then returned, attached the EMG and EOG electrodes, and gave any final instructions. After these instructions the experimenter returned to the equipment room, and once the vaginal measures had stabilized (usually 15 to 20 minutes after probe insertion), the experimenter instructed the subject to have a sexual fantasy. The fantasy lasted until the subject reported she could no longer hold the fantasy or for 5 minutes, whichever came first. Following the fantasy, the subject was asked to provide subjective ratings of the degree of sexual arousal and pleasure produced by the fantasy, plus the clarity of the imagery. Once the measures had again stabilized, the subject was asked to have a second sexual fantasy. Initially, we had planned on comparing the sexual arousal associated with the fantasies with the sexual arousal during REM sleep, similar to the procedure of Cohen
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Journal of Sex and Marital Therupy
and Shapiro.'% However, the large variability between subjects' data during the fantasies as compared to the relatively small variability between subjects' data associated with the REM responses precluded any meaningful comparison. Following the second fantasy, subjects were told they could go to sleep. Either one of the experimenters or a technician monitored the record throughout the night, labeling on the record any movement artifact or any time the subjects reported being awake during the night. In the morning when the subject awoke, the experimenter entered the room, removed the electrodes, and left so the subject could remove the photoplethysrnograph. Between recording nights the vaginal probe was sterilized in Zephiran Chloride ( I to 750 dilution) and rinsed in water. T h e procedures for the second night of recording were identical to those used during the first night. 'Time between recordings ranged from the next night t o one week.
Quantifzcation of data. To determine REM periods, the polygraph was visually inspected and REM periods were defined by increases in EOG activity with concommitant decreases in EMG activity. Because of equipment limitation, an EEG was not available, which at times complicated a clear determination of REM periods. However, a conservative approach was taken, and any questionable REM periods were not included, even though they were associated with typical changes in the vaginal recordings. Once the REM period was det.ermined, the following data were scored for that period: (1) maximum relative blood volume in mm of pen deflection from the middle of the polygraph channel, (2) minimum blood volume in mm of pen deflection from the middle of the polygraph channel, and (3) maximum averaged pulse pressure from the 7P3 integrator scored in mm of pen deflection from the bottom of the polygraph channel. For comparison purposes a pre-REM period was established by sampling a 2-minute interval beginning 4 minutes prior to the onset of each REM period. This pre-REM period was scored as above for the same three dependent variables. Data were excluded that were accompanied by movement artifact detected on the basis of either polygraph recordings o r subject-produced movement sounds heard over the intercom. Data to he presented include the three vaginal measures during REM sleep periods for the one night of clearest recording. Only one night of dat:a is reported because, i n some instances, excessive artifact due to problems sleeping o r equipment difficulties preclude the use of data from the other night's recording.
RESULTS Figures 1 through 3 reflect the results of a typical subject during the various instructions and during sleep. Figure 1 shows the EOG, EMG, the three measures of relative pulse pressure (cumulative, averaged, and A.C. pulse amplitudes), and the D.C. relative blood volume during no instructions (pre-fantasy) and instructions to have a sexual fantasy (fantasy). While awake and reporting a sexual fantasy, the subject's A.C. pulse amplitude and D.C. blood volume both increase. Figure 2 shows the same subject's physiologic measures during a preREM period with minimal EOG activity, high EMG activity, and baseline D.C. and A.C. measures. With the onset of REM sleep (Figure 3) EOG activity increases, the EMG amplitude decreases, and there is both a marked increase in pulse amplitude and a concomitant, dramatic decrease in blood volume.
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Gene G.Abel, MD. el al.
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FIGURE 1: EOG, EMG, A.C., and D.C. Vaginal Pulse Amplitudes Before and D u r ing Sexual Fantasies.
A summary of all REM periods for all subjects is presented in Table 1, which indicates change scores for each subject from pre-REM baselines including maximum relative blood volume‘(MAX-BV), minimal relative blood volume (MIN-BV), and maximum averaged relative pulse pressure (MAX-PP). Table 1 is a summary of individual subject data for the largest response of the night based on each subject’s MAX-PP (left-hand columns) and the means for all REM periods observed in each subject during a single night (right-hand columns). From Table 1, a typical vaginal response pattern can be observed with a drop in MIN-BV and a concomitant increase in the MAX-PP measures. This pattern is observed for all eight subjects and is the same whether the maximum response of the night is inspected or the mean values are taken for all REM periods during the night. T h e MAX-BV score is less consistent with a slight overall increase in MAX-BV during REM when the means of all the REM periods are inspected. T h e conclusions from visual inspection of the data are supported statistically when correlated t-tests22are applied to the data. For the maximum response of the night (left-hand columns of Table 1) this analysis indicates no significant difference between the pre-REM periods and REM
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Journal of Sex and Murital Therapy
FIGURE 2: LOG, EMG, A.C., and D.C. Vaginal Pulse Amplitudes during Non-KEM Sleep.
periods for MAX-BV (t = 1.47, df = 7, n.s.); a significant increase in the MAX-PP ( t = 10.55, df = 7 , p < .001) over the pre-REM period; and a significant decrease in MIN-BV ( t = 7.70. df = 7, p < ,001). When the mean values (right-hand columns of Table 1) were analyzed with the same statistical procedure, the results were similar to the analysis of MIN-BV and MAX-PP (with p < -001) during the MAX-REM period. However, in this second analysis, the increase in MAX-BV ( t = -3.48,df = 7,p < .02), indicated a significant increase in blood volume over the pre-REM period for the mean values during REM. It should be noted that the MIN-BV changes are somewhat smaller than what actually occurred because in four of the REM periods (two of which are represented in the MAX-REM periods in Table 1) the recording pen dropped off channel. When this occurred, the value recorded was the mm of pen deflection at the point the pen dropped off channel, which is an underestimation of what the true value would have been if the total drop in BV could have been recorded.
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Gene G . Abel, MD, et al.
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FIGURE 3: EOG, EMG, A.C., and D.C. Vaginal Pulse Amplitudes During REM Sleep.
The data for the means of all REM periods for each subject and the MAX-REM response of the night indicate a high degree of consistency. To further investigate this consistency, all 31 REM periods observed across all subjects were inspected. A frequency count was taken for all periods where the MAX-BV, MIN-BV, and MAX-PP showed a change of 10 mm or more from the pre-REM period. Results from this analysis indicate that for MAX-BV an increase of 10 or greater was found in only 9/3 1 of the REM periods, while for MIN-BV a decrease of 10 or more was found in 2613 1 of the REM periods. For the MAX-PP an increase of 10 or greater occurred in 19/31 of the REM periods. It was also observed that in none of the 31 REM periods was the MAX-PP measure less than that observed in the pre-REM periods nor was the drop in BV less than or equal to drops observed in pre-REM periods. However in 6/31 periods the value observed for MAX-BV was less than or equal to that observed in the pre-REM periods, suggesting again that MAX-BV increases are an inconsistent finding during REM periods.
Journal of Sex and Marital Therapy
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I
W. REM PERIOD
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8
MEAN
OF ALL REM PERIODS
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-16.20
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I
DISCUSSION
These results indicate that normal females have a specific vaginal response pattern during sleep. Females show periodic increases in relative pulse pressure and, contrary to our expectations, a concomitant decrease in relative blood volume during REM sleep. In some instances there is a biphasic response in BV; however, the increase in BV observed during REM is small and not as dramatic as the decrease in BV or the increase in PP. The increased BV may be a reflection of the scoring system used. Until further data are collected, the vaginal responses of females during sleep are most reliably described as a decrease in BV associated with an increased in PP. Within the limitations of the physiological measures obtained, these phasic changes appear to occur during REM sleep similar to the nocturnal REM erection observed in male^.^,',^ Cohen and Shapirol9 and Shapiro, Cohen, DiBianco, and Rosen,20 have shown increases in blood flow to the vagina during sleep in females using an isothermal measurement device. These studies are consistent with the increases in pulse pressure observed in the present investigation since pulse pressure has been found to correlate with blood f10w.23*24In
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contrast, it would appear that the blood volume measure obtained from the walls of the vagina is inconsistent with the data reported by Karacan et aL8 They found increased engorgement of the clitoris while recording from females with congenitally enlarged clitorises. It is possible that during REM sleep the vascular response of the clitoris is different physiologically from the vascular response of the walls of the vagina or that the physiologic abnormalities of the subjects measured by Karacan led to results different from the normal females used in this study. Further research is necessary to explore the discrepancies in these studies. The decrease in blood volume during REM sleep was unexpected, given the results of Masters and Johnson,25which suggest that during the waking state, female sexual arousal is accompanied by vasocongestion. In addition, photoplethysmographic studies demonstrate increases in blood volume and pulse pressure during sexual a r o u ~ a l . ’ ~ ” ~However, ”* if the photoplethysmographic response is recorded during orgasm rather than the early excitement phase, a pattern is observed very similar to the sleep records of the present study. Geer and Q ~ a r t a r a r o ’reported ~ photoplethysmographic records of seven females during masturbation. In each case a decrease in BV was observed when orgasm was reported. Because of artifact, the PP measure could not be observed during six of the seven orgasms. However, there was an increase in PP during masturbation, which was maintained during the resolution phase following orgasm. In the one case where PP could be interpreted, an increase was observed during orgasm while the BV decreased concomitantly, similar to the present sleep data. It is possible that the pattern of results in this sleep study are similar to the orgasmic phase of sexual arousal rather than the excitement or plateau phase.25 Although speculative, this hypothesis does seem to warrant further investigation. The major criticism of the present study is the failure to include an EEG measurement to assist in defining REM periods. However, the scoring of the data was conservative, leading to the exclusion of some of the largest vaginal responses of the night, even though these responses followed the exact pattern of the data presented. Secondly, the measures that were obtained (EMG and EOG) are consistently associated with REM sleep. EMG decreases seem especially indicative of REM sleepz6and was one of the variables used to define REM in the present study. Whether the pattern of vaginal responses observed in this study occurred during REM or non-REM periods may not be critical should the presence or absence of these responses be found to be of diagnostic value in separating the organic from psychogenic causes of sexual dysfunctions in females. Currently, the phasic erections observed in males do not depend on their being coincident with REM periods to assist in the differential diagnosis of sexual dysfunctions. Instead, it is the absolute size
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Journal o j Sex und Marital Therupy
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of erection that the male gets during sleep that allows impotence to be categorized as psychogenic or organic in etiology. Only further studies measuring the sexual responses of dysfunctional women during REM will determine if vaginal photoplefhysmographic measures will separate the psychogenic from the organic sexual dysfunctions of women.
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1971. 2 . Abel GG: Recent research on the evaluation and treatment of the rapist. In M Walkcr (Ed), Rape: Research, Acfion, Prevention. Proceedings of the Sixth Alabama Symposium on Justice and the Behavioral Sciences, Tuscaloosa, 1975. 3 . Abel GG: Assessment of Sexual deviation in the male. In M Hersen, AS Bellack (Eds). Behavioral Assessment: A Practical Handbook. New York, Pergamon, 1976, p 437. 4 . Abel GG, Blanchard EB: T h e measurement and generation of sexual arousal in male sexual deviates. In M Hersen, R Eider, PM Miller (lids), Progress in Behavior Modijication, Vol 2. New York, Academic Press. 1976, p 99. 5. Freund K: Laboratory differential diagnosis of homo- and heterosexuality: An experiment with faking. Rev Crrch Mtd 7:20-3 I , 196 1. 6. Fisher C, Schiavi R, Lear H , e t al: T h e assessment of nocturnal REM erection in the differential diagnosis of sexual impotence. J Sex Marital Ther lr277-289, 1975. 7 . Karacan I : Clinical value of nocturnal erection in the prognosis and diagnosis of impotence. Med Aspects Hum Sex 4:27-34, 1970. 8. Karacan I, Williams RI., ‘I’hornby JI. Salk PJ: Sleep-related penile tumescence as a function of age. A m J Psychiatry 132:932-937, 1975. 9. Abelson D: Diagnostir value of the penile pulse and blood pressure: A doppler study of impotence in diabetics. J Ur01113:636-639, 1975. 10. Britt DR, Kcmmerer WI’, Robison JR: Penile blood flow determination by mercury strain gauge plethysmography. Inue.$t Urol8:673-678, 1971. 1 1 . Ellenberg M : Impotence in diabetes: T h e neurologic factor. Ann Intern Med 75:213-219, 1971. 12. Ellenberg M, Weber H : T h e incipient asymtomatic diabetic bladder. Diabetes 16:331-339, 1967. 13. Ceer J , Morokoff P, Greenwood P: Sexual arousal in women: T h e development of a measurement device for vaginal blood volume. Arch Sex B t h v ?:559-564, 1974. 14. Sintchak G,Geer J: A vaginal photoplethysmograph system. Psychophysiology 12: 113-1 15, 1975. 1.5. Geer J H , Quartararo JD: Vaginal blood volume responses during masturbation. Arch Sex Behau 5:403-413, 1976. 16. Heiman JR: T h e physiology of erotica: Women’s sexual arousal. Psycho1 Today, April 1975,91-94. 17. Hciman JR: A psychophysiological exploration of sexual arousal patterns in females and males. Psychophysiology 14:266-274, 1977. 18. Hoon PW, Wincze JP, Hoon EF: Physiological assessment of sexual arousal in women. Psychophysiology 13: 196-204, 1976. 19. Cohen HD, Shapiro A: Vaginal blood flow during sleep. Psychophysiology 7:338, 1970. 20. Shapiro A, Cohen H, DiBianco P, Rosen G: Vaginal blood flow changes during sleep and sexual arousal. Psychophysiology 4:394, 1972. 21. Karacan I , Rosenbloom AL, Williams KL: T h e clitoral erection cycle during sleep. Psychophysiology 7:338, 1970. 22. Bruning JL, Kin12 BL: Computational Handbook of Statistics. Glenview, Ill, ScotdForesman, 1968. 23. Burton AC: T h e range and variability of the blood flow in the human fingers and vasomotor regulation of body temperature. Am J Physiol 127:437-453, 1939. 24. Hertzman AB, Randall WC, ]ochim KE: The estimation of the cutaneous blood flow with the photoelectric plethysmograph. A m J Physiol 145:716-726, 1946. 25. Masters WH,Johnson VE: Human Sexual Response. Boston, Little Brown, 1966. 26. Bliwise D, Coleman R, Bergman B, Wincor RT, Pivik RT, Rechtschaffen A: Facial muscle tonus during REM and NREM sleep. Psychophysiology 11:497-508, 1974.
