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Published on: August 2, 2017
The dynamics of affect across the wake-sleep cycle: From waking mind-wandering to night-time dreaming
Pilleriin Sikka1, Katja Valli1, Antti Revonsuo1
1Department of Psychology and Speech-Language Pathology, University of Turku, Finland; Turku Brain and Mind Center, University of Turku, Finland; Department of Cognitive Neuroscience and Philosophy, University of Skövde, Sweden.
Abstract:
Affective experiences occur across the wake-sleep cycle-from active wakefulness to resting wakefulness (i.e., mind-wandering) to sleep (i.e., dreaming). Yet, we know little about the dynamics of affect across these states. We compared the affective ratings of waking, mind-wandering, and dream episodes. Results showed that mind-wandering was more positively valenced than dreaming, and that both mind-wandering and dreaming were more negatively valenced than active wakefulness. We also compared participants' self-ratings of affect with external ratings of affect (i.e., analysis of affect in verbal reports). With self-ratings all episodes were predominated by positive affect. However, the affective valence of reports changed from positively valenced waking reports to affectively balanced mind-wandering reports to negatively valenced dream reports. These findings show that (1) the positivity bias characteristic to waking experiences decreases across the wake-sleep continuum, and (2) conclusions regarding affective experiences depend on whether self-ratings or verbal reports describing these experiences are analysed.
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