We found that relative to participants with secure attachment orientations, those with an anxious orientation evidenced reduced latencies to REM sleep; relative to participants with avoidant attachment orientations those with an anxious orientation also evidenced significantly enhanced aggression/friendliness content and greater self-negativity content in dreams recalled after a REM but not a NREM awakening.
McNamara et al. (2001)
proposed that REM sleep is used by preoccupied or, more broadly conceived, attachment-anxious individuals to process attachment-related experiences and emotions, and that REM sleep is consequently up-regulated (increased in duration and intensity as measured by indices of REM sleep architecture and REM-related mentation such as dream recall and content) in such individuals. In contrast, avoidant individuals, who are known to use defenses to down-regulate (or “deactivate”; Cassidy & Kobak, 1988
; Mikulincer, Dolev, & Shaver, 2004
) attachment processes when awake, may also down-regulate the processing of attachment-related memories and emotions during sleep (as indicated by decreased duration and intensity of indices of REM sleep architecture and REM-related mentation such as dream recall and content). Those with secure orientations were predicted to fall between the high REM values associated with anxious orientations and the low REM values associated with avoidant orientations.
The results from our sleep measurements, however, provide only mixed support for McNamara et al.’s (2001)
suggestion concerning a role for REM sleep in the maintenance of attachment orientations in anxiously attached individuals. While measurements of REM sleep indices were in the predicted directions, they were not always significant. One of the main predictions flowing from McNamara et al.’s theoretical suggestions was that REM sleep-related mentation
would be associated with emotional memory content and internal working models of attachment. Thus, the self would be negatively evaluated (compared with the evaluation of a significant other) by anxious participants in REM dreams and after REM awakenings. By contrast the self would be positively evaluated by avoidant participants in their dreams and after awakenings. But statistical tests of these associations did not reach significance. Nevertheless, solid statistical support for the theory suggested by McNamara et al. (2001)
was obtained when measures of REM sleep latency and broader categories of REM dream content measures were analyzed.
There was higher REM sleep pressure (in the form of shorter latencies to REM) noted in the anxious group as compared with the secure groups. This was not due to depression, because people with a history of depression were excluded from the study and no signs of depression emerged on the DASS mood scales. Indeed there were no significant differences on the DASS depression scale between the three attachment groups. In addition, there were no significant differences between the avoidant, anxious, and secure categories on the PANAS mood scales after awakenings.
Another possibility that might explain greater REM sleep pressure and enhanced dream recall in the anxious participants was that they were simply over-aroused. But the PANAS “alert” item ratings after awakenings from REM and NREM sleep did not vary across the three attachment groups, and there were no significant differences on PSG-measured arousal or sleep efficiency across the three attachment groups ().
Why, then, do individuals who score high on anxious attachment exhibit enhanced REM sleep pressure, greater aggression and enhanced self-denigration themes in their dreams? Because there is considerable evidence that attachment-anxious individuals are emotional, expressive, ambivalent, and prone to rumination (see Mikulincer & Shaver, 2007
, for a review), they may exhibit these same kinds of tendencies while sleeping (see Mikulincer, Shaver, & Avihou-Kanza, this issue). It may also be that anxious individuals who are emotionally preoccupied with a significant other may harbor aggressive feeling toward that individual as well. Avoidant individuals, in contrast, tend to inhibit or suppress emotion and try not to think about emotional vulnerabilities while awake. Some of the same defensive processes may operate while they are asleep.
Participants in our study classified as avoidant had significantly elevated Pittsburgh Sleep Quality Index scores indicating poorer sleep, compared to participants classified as secure. This poor quality sleep is consistent with the idea that these individuals defensively resist sleep because sleep and sleep mentation involves some amount of processing of attachment-related content and unpleasant emotional memory content.
In other words, the sleeping and dreaming mind/brain shares many tendencies with the waking mind/brain. Attachment working models are well ingrained organizers of the mind, and they may continue to organize or influence mental processes during sleep. This is one of the reasons why, ever since Freud, dream reports have been valuable sources of insight about underlying conflicts, preoccupations, and defenses.
Freud also pointed to the importance of early childhood experiences in the formation of lifelong psychic and emotional functioning. These early observations of Freud suggest that it may be possible that attachment orientations that are formed in early childhood will be associated with later adult functioning, including sleep and dream function. Csóka et al. (this issue) examined potential associations in a large sample (n = 5020) of otherwise healthy adults between early maternal separation and nightmare and dream content experience in adulthood. They found significant associations between early maternal separation and frequent nightmares and negative dreams. Current depression contributed to the association between early separation and nightmares, but not the association between negative dream affect and early separation. Taken together with the results reported concerning REM pressure and negative dream content in participants classified with an anxious attachment orientation it seems clear that the deep associations between attachment and sleep and dream function that Freud pointed to over a century will require further and sustained exploration.