| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
ORIGINAL ARTICLES |
From the Department of Psychology, University of Rome "La Sapienza," Rome, Italy.
Address reprint requests to: Luigi De Gennaro, PhD, Sezione di Neuroscienze, Dipartimento di Psicologia–Università degli Studi di Roma "La Sapienza," Via dei Marsi, 78, 00185 Roma, Italy. Email: luigi.degennaro{at}uniroma1.it
 |
ABSTRACT |
|---|
 TOP ABSTRACT INTRODUCTIONMETHODSRESULTSDISCUSSIONNOTESACKNOWLEDGMENTSREFERENCES |
|---|
METHODS: Ten alexithymic and 10 nonalexithymic women were selected from a larger sample of 160 undergraduate students. The transcriptions of their audio-recorded dream reports on 14 consecutive morning awakenings were compared with regard to their length and emotional content. Self-ratings obtained from sleep and dream diaries were further considered to assess between-groups differences in dream recall frequency and in the emotional valence, vividness, and bizarreness of dreams.
RESULTS: Dream recall frequency and mean length of dream reports were lower in alexithymic than in nonalexithymic subjects. There were no significant between-groups differences in emotional valence, vividness, bizarreness, and emotions scored according to the Hall and Van de Castle coding system.
CONCLUSIONS: The results suggest a general difficulty of alexithymics in accessing (recalling) their dreams.
Key Words: alexithymia, • emotional regulation, • dream recall, • sleep.
Abbreviations: ANCOVA = analysis of covariance;; ANOVA = analysis of variance;; EEVD = external emotional valence of dream;; IEVD = internal emotional valence of dream;; REM = rapid eye movement;; SEM = standard error of mean;; TAS-20 = 20-item Toronto Alexithymia Scale;; TNE = total number of emotions;; TWC = total word count.
|
INTRODUCTION |
|---|
|
TOPABSTRACTINTRODUCTIONMETHODSRESULTSDISCUSSIONNOTESACKNOWLEDGMENTSREFERENCES |
|---|
The early clinical impression that alexithymia is also associated with lower and/or impoverished dream recall (2) has been empirically assessed in the last years. Indirect evidence came from two studies in patients with asthma and eczema. Monday et al. (3) found more content-less dreams in asthmatic patients, who usually score highly on alexithymia (4), and Tantam et al. (5) reported a lack of involvement in dreams of eczematic patients with alexithymia. Furthermore, a moderate negative relationship between alexithymia, particular externally oriented thinking, and frequency of dream recall was shown by Nielsen et al. (6) in a retrospective study of asthmatic men; this correlation was not significant in women. More directly, Ouellet et al. (7) awakened six alexithymic and five nonalexithymic women from all REM sleep periods, collecting their dreams. They showed a lower proportion of recalled dreams in alexithymics without any significant difference in length or emotions of dream reports. With the same approach, Parker et al. (8) compared an alexithymic group (N = 8) to a nonalexithymic group (N = 8) of subjects whose dreams were recorded after three nocturnal awakenings from REM sleep but found no difference in the number, length, and emotional valence of dreams. The only significant difference was in the fantasy ratings scored by the experimenters, which were lower in alexithymics. Finally, Lumley and Bazydlo (9) carried out one retrospective and one prospective study. In the retrospective study, they surveyed a large number of nonclinical subjects, assessing the relationship between alexithymia and answers to four questions on dream activity. They found only a moderate negative correlation (r = -0.11) between externally oriented thinking and dream recall frequency, whereas difficulty identifying feelings and difficulty describing feelings correlated positively with the number of dreams without details and the number of disturbing dreams. In the prospective study, they asked 153 nonclinical subjects to write their dreams after morning awakening for 7 consecutive days, showing as main results significant correlations between externally oriented thinking and dreams without details (r = -0.24), lack of dreams (r = 0.17), and number of words (r = -0.27).
In short, results seem to be contrasting, and effects (when present) are moderate and often imply different aspects of dream recall in different studies. This puzzling picture is partially explained by discrepancies in the procedure of collecting dream reports and by the representativeness of subject dream production (ie, the problem of having a stable measure of individual dream production).
There is no doubt that awakening subjects during REM sleep periods is the best procedure for maximizing the frequency of dream recall (eg, Stickgold et al. (10) reported a recall rate of 85%; Foulkes and Schmidt (11) reported a rate of 83%). But the costs of sleep polysomnography preclude the collection of a large sample of dream reports, which could be obtained only by studying the same subjects for several consecutive nights or by studying many subjects. Furthermore, laboratory dreams are usually different from those recalled at home (12,13) . On the other hand, retrospective investigation based on dream recall is quite inaccurate and provides only a poorly reliable estimation of dream activity (14). Home diaries seem to be the only available procedure that guarantees a representativeness of dream production, because subjects can be asked to collect their dreams in their own homes over long periods. In this case, the most direct protocol to collect dreams is represented by the use of tape recording, instead of writing dreams, just on morning awakening (10); moreover, this protocol allows us to more reliably assess qualitative (content) aspects of dream activity.
In addition to these methodological remarks on the previous studies on the issue of impoverishment of dreaming in alexithymia, no psychometric evaluation of the emotional characteristics of dreaming in alexithymic and nonalexithymic subjects has yet been provided.
Since the 1960s, the Hall and Van de Castle coding system (15) has been the most widely used (and comprehensive) method for studying dream content; this system scores all explicitly mentioned emotions experienced by the dreamers in five subcategories: anger, apprehension, happiness, sadness, and confusion. In line with the hypothesis that differences in emotional regulation (or dysregulation) in alexithymics also spreads to dream production, the emotions category of the Hall and Van de Castle system could discriminate emotional contents in the dream reports of two groups of alexithymic and nonalexithymic subjects.
We selected subjects from a large sample of undergraduate students and collected a 2-week dream diary (by audio recordings) on morning awakening to compare quantitative (length and frequency) and qualitative (content) aspects of dream production of alexithymic and nonalexithymic subjects. Furthermore, sleep quality, as measured by subjective estimates of sleep characteristics of the preceding night (sleep onset latency, number of awakenings, total sleep time), were compared between the two groups.
|
METHODS |
|---|
|
TOPABSTRACTINTRODUCTIONMETHODSRESULTSDISCUSSIONNOTESACKNOWLEDGMENTSREFERENCES |
|---|
Depression was also assessed by means of the Italian version of the Center for Epidemiologic Studies Depression Scale (17), and the two groups did not show significant differences (alexithymic: mean = 22.22, SEM = 3.75; nonalexithymic: mean = 15.40, SEM = 3.50; F(1,18) = 1.77, p = .20).2
Participants were required to maintain regular sleep habits during the 2 weeks in which they recollected their dreams. They were unaware of the purpose of the experiment. Experimenters were blind to subjects’ group assignments.
Procedure
Subjects were asked to record their dreams after each morning awakening by dictating them into a handheld tape recorder. Each subject was instructed to give an explicit description of any aspect of the dream and, when more than one dream was recalled, to specify in the dictation when a different dream was reported.
After recording the dream on tape, the subject completed a sleep and dream diary. This provided information on subjective estimates of sleep characteristics (sleep onset latency, number of awakenings, total sleep time, sleep quality) and on dream experience (number of dreams and emotional valence, vividness, bizarreness, and length, which were rated using a 6-point scale) during the preceding night.
The Hall and Van de Castle Coding System
This system applies content analysis to dream reports to categorize units of qualitative material to obtain frequencies that can be subjected to statistical analyses. Application of the Hall and Van de Castle system provides the largest and most systematic body of findings about what people dream. This system consists of eight general categories (most of them are also divided into two or more subcategories): characters (animals, humans, creatures), social interactions (friendly, aggressive, sexual), activities (physical, nonphysical), striving (success, failure), misfortune and good fortune, emotions (anger, apprehension, happiness, sadness, confusion), physical surroundings (settings, objects), and descriptive elements (modifiers, temporality, negativity). For the emotions category, the coding system measures only explicit dream emotions.
Because categories are nominal in nature and are clearly defined, interscorer reliability is very high, and it is usually determined by the method of "perfect agreement" (ie, the number of similar codings divided by the sum between the number of agreements and of disagreements). Hall and Van de Castle (15) provided normative values for young men and women based on five dreams each from 100 male and 100 female college students. All or parts of these normative values have been confirmed many times (18–21 ). With regard to the emotions category, Hall and Van de Castle (15) analyzed 1000 home dream reports from 500 male and 500 female college students. About 700 emotions were counted, and 80% of them were negative. About half of these were categorized as apprehension; the remaining half were anger, sadness, or confusion.
Data Analysis
Tape recordings were transcribed verbatim into dream reports. Two independent experimenters (L.D.G. and V.M.) scored the dream reports according to the Hall and Van de Castle coding system (15), using its emotions category, which is divided into five subcategories: anger, apprehension, happiness, sadness, and confusion. Total number of emotions (TNE) is the sum of the five subcategories. Means of the five subcategories and TNE were based on the ratio between the number of emotions and the number of days in which subjects recalled dreams. Furthermore, these two judges provided a comprehensive rating (based on a 6-point scale) of the emotional intensity of each dream (external emotional valence of dream, EEVD) corresponding to subjects’ self-ratings of emotional intensity (internal emotional valence of dream, IEVD) included within the sleep and dream diary. In other words, judges also gave a comprehensive rating of emotional intensity for each dream provided by the subjects in the daily sleep and dream diary.
Finally, the number of dreams was counted for each daily dream report (total number of dreams/14 days), and the total word count was expressed both by a similar index (total number of words/14 days; TWC1) and by the ratio between the total number of words and the number of days in which subjects recalled dreams (TWC2).
Dependent variables for the between-groups comparisons were mean sleep characteristics, subjectively estimated by the subjects in the sleep and dream diary (sleep latency; total sleep time; difficulty in falling asleep; number of awakenings; difficulty in falling asleep after nightly awakenings; total awakening time; time in bed after final awakening; sleep comfort and depth; sleepiness, satisfaction, tiredness and calmness on final awakening); number of dreams/14 days; TWC; EEVD; IEVD; anger; apprehension; happiness; sadness; confusion; and TNE (which corresponded to anger + apprehension + happiness + sadness + confusion).
Interrater reliability was as follows: for EEVD, r = 0.68; anger, r = 0.86; apprehension, r = 0.79; happiness, r = 0.94; sadness, r = 0.74; confusion, r = 0.81; and TNE, r = 0.85. Differences in coding were resolved by a third independent scorer so that there would be one set of codings.
Each dependent variable was submitted to a one-way analysis of variance (ANOVA) to compare alexithymic vs. nonalexithymic subjects. Furthermore, correlations between EEVD and IEVD and between TWC and TNE were calculated. The former were carried out to assess the correspondence between subjective and objective estimates of emotion in dreams, the latter to control if TNE was related to the length of dream reports. To control for report length in case of a significant correlation, analysis of covariance (ANCOVA) was used to compare the two groups on TNE with TWC as a covariate measure; the aim of this analysis was to assess between-groups differences in the number of emotions partialing out the contribution of dream report length to the probability of describing an emotion.
|
RESULTS |
|---|
|
TOPABSTRACTINTRODUCTIONMETHODSRESULTSDISCUSSIONNOTESACKNOWLEDGMENTSREFERENCES |
|---|
|
|
Variables obtained by scoring the dream reports correlated with the corresponding subjective estimates provided by the sleep and dream diary. The number of dreams scored within transcriptions was highly correlated with the subjective estimate of the number of dreams (r = 0.88, p = .0001), and a significant correlation was also found between subjective (IEVD) and objective (EEVD) emotional valence of dreams (r = 0.68, p = .001).
The variables obtained by the scoring of dream reports were then compared between groups by means of ANOVAs. Table 2 details these comparisons. A significantly higher number of dreams and total word count (considering both TWC1 and TWC2) was found in the nonalexithymic group. Because the length of dream reports and dream recall frequency were also intercorrelated (r = 0.89, p < .0001), these between-groups differences reflect a general decrease of the quantitative aspects of dream mentation in the alexithymic subjects. Smaller differences were found with respect to the qualitative aspects of dream mentation, that is, the number and the type of emotions. Although the five subscales of the Hall and Van de Castle system did not show any significant between-groups difference, there was a statistical tendency (p < .10) toward a greater prevalence in TNE by the nonalexithymic subjects as compared with alexithymic subjects.
However, it should be considered that the probability of showing emotions in a dream report can be related to dream report length. In fact, the correlations between TNE and TWC1 (r = 0.44, p = .05) and TWC2 (r = 0.50, p = .03) were significant. Therefore, an ANCOVA was carried out on the TNE values of the two groups with TWC1 as a covariate. Any difference between groups dis-appeared (F(1,17) = 1.01, p = .33), and the effect of the covariate was also not significant (F(1,17) = 1.84, p = .19).
Because it could be argued that longer dream reports may be needed to describe more emotions, another ANCOVA was carried out, comparing the two groups on TWC1 with TNE as a covariate. In this case the difference between alexithymic and nonalexithymic subjects did not disappear but approached significance (F(1,17) = 2.98, p = .10), whereas the effect of the covariate was again not significant (F(1,17) = 1.46, p = .24).
Finally, it should be mentioned that the accuracy in estimating characteristics of dreams seems to depend on the characteristics of the dream production (ie, quantitative or qualitative aspects): alexithymic subjects show a much higher correlation between their subjective estimate of length and the word count (r = 0.63, p = .03) than nonalexithymic subjects (r = 0.17, p = .67), whereas the correlation between EEVD and IEVD is lower in the alexithymic group (r = 0.57, p = .09) as compared with the nonalexithymic group (r = 0.84, p = .002).
|
DISCUSSION |
|---|
|
TOPABSTRACTINTRODUCTIONMETHODSRESULTSDISCUSSIONNOTESACKNOWLEDGMENTSREFERENCES |
|---|
One limitation of our study is that it included only female subjects.3 This choice was aimed at maximizing the probability of having more and longer reports, because large-scale surveys have shown that women have a higher frequency of dream recall (22) and that gender difference is not affected by sleep quality or emotional balance (23). Future research should assess whether the impoverished dream mentation of alexithymic women is also confirmed in men.
The congruity of results between dream recall frequency and dream report length points to a general difficulty of alexithymics in accessing (recalling) dream production. Whether there is indeed only a deficit in accessing or even in producing dream experience is open to speculation. By definition, the direct study of dream experience is still inaccessible to experimental investigation, and dream mentation is the only way to approach dreaming. However, if alexithymia also affects the mechanisms of dream production, it should be associated with changes in polysomnographic measures, that is, the physiological scenario in which dreaming is produced. In fact, the few studies on this specific issue do not seem to indicate the existence of unequivocal differences in sleep staging (7, 24, 25) . At present we think it is more parsimonious to hypothesize that alexithymia negatively affects only the phenomenon of recalling dreams.
The association between alexithymia (or some of its facets) and a decrease of dream recall frequency is in general consistent with the previous studies (eg, Refs. 6, at least for their male subjects, 7, and 9) with the exception of Parker et al.(8), who reported a nonsignificant prevalence of TWC of nonalexithymic as compared with alexithymic subjects.
Our results on the quantitative aspects of dream mentation and the concomitant failure in showing any difference between groups with respect to the emotional contents of dream mentation (both internally or externally rated) could shed some light on the puzzling picture of results depicted in the "Introduction." The few findings of a relationship between alexithymia and content aspects of dream mentation (Tantam et al. (5), more content-less dreams; Monday et al. (3), lack of involvement in dreams) could be explained as a byproduct of the lower length of dream reports of alexithymics. A similar explanation concerns the lower fantasy ratings scored in the dream reports of alexithymic subjects reported by Parker et al. (8) since they also found a correlation between fantasy ratings and word counts (r = 0.68). Actually, the only finding controlling for dream mentation length (9) indicated more unregulated (3% of explained variance) and less engaging (5% of explained variance) dreams in subjects scoring higher in alexithymia, but it failed to showing any correlation with emotions.
Interestingly, our alexithymic subjects seemed more accurate in estimating the length of dreams because the correlation between their subjective estimates and the word counts was much higher than that of nonalexithymic subjects. But the alexithymic subjects seemed to have more difficulty in estimating the emotional valence of dreams; that is, their correlation with external estimates of emotional valence was lower than that of nonalexithymic subjects. Although the greater accuracy in estimating dream length is probably explained by the brevity of their reports, the rate of the emotional valence adheres to their difficulty in identifying emotions. It could be said that some minutes before (during sleep), they were not different from nonalexithymic subjects in expressing emotions during their dreams, whereas some minutes after (on awakening, when they were asked to recall and record their dreams), they again became less capable of recognizing emotions.
|
ACKNOWLEDGMENTS |
|---|
|
TOPABSTRACTINTRODUCTIONMETHODSRESULTSDISCUSSIONNOTESACKNOWLEDGMENTSREFERENCES |
|---|
|
NOTES |
|---|
|
TOPABSTRACTINTRODUCTIONMETHODSRESULTSDISCUSSIONNOTESACKNOWLEDGMENTSREFERENCES |
|---|
2 According to the Italian cutoff point of 23 (17), four alexithymic and three nonalexithymic subjects were classified as depressed.
3 Nevertheless, it should also be mentioned that the only study reporting sex differences with respect to the association between alexithymia and dream features (6) found a correlation between alexithymia scores and a retrospective measure of dream recall frequency in only male subjects.
Received for publication September 5, 2001.
|
REFERENCES |
|---|
|
TOPABSTRACTINTRODUCTIONMETHODSRESULTSDISCUSSIONNOTESACKNOWLEDGMENTSREFERENCES |
|---|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
