A Comparison of Mental Activity During Sleep Onset and Morning Awakening

Abstract

The aims of the experiment were: (1) to establish the proportion of sleep stages in morning spontaneous awakening and to observe whether any stage-dependent differences can be found in the mentation reports; and (2) to compare the characteristics of mental activity during sleep onset (SO) and during the latest sleep period. One hundred forty-four dream reports and their association reports were collected from 36 subjects in a lab experimental design. Dream reports were analyzed as to structure (length, narrative continuity), content (self, setting, lab references, nonself characters, dimensional distortions, body feelings, bizarreness and emotions), and awareness (reality testing). Associations were classified as episodic, abstract self-referred, and semantic memories. The morning awakenings results were not affected by the stage of sleep during which dreaming occurs. SO reports prevalently show a lifelike nature, while sleep-offset reports are prevalently dreamlike. On the other hand, there seems to be a similar availability of mnemonic systems in the two sleep conditions.

As we fall asleep we forget about the future: A quantitative linguistic analysis of mentation reports from hypnagogia

“…In comparison to sleep offset mentation, sleep onset mentation has been described as less dreamlike with respect to bizarreness, emotion, and awareness about the current situation (Cicogna, Natale, Occhionero, & Bosinelli,1998). However, in previous studies, report judges could not detect differences between mentation reports from sleep onset and sleep offset with regard to references to memories (Cicogna et al, 1998). In how far hypnagogic imagery draws from memory input has previously been studied by systematic self-observation procedures in which the investigator observed and analysed his own hypnagogic imagery in spontaneous drowsy episodes during the day (Nielsen, 1995): According to this investigation, four types of memory sources (immediate-, short-, medium-, and long-term) appear to feed into hypnagogic imagery (Nielsen, 1995).…”

“…In how far hypnagogic imagery draws from memory input has previously been studied by systematic self-observation procedures in which the investigator observed and analysed his own hypnagogic imagery in spontaneous drowsy episodes during the day (Nielsen, 1995): According to this investigation, four types of memory sources (immediate-, short-, medium-, and long-term) appear to feed into hypnagogic imagery (Nielsen, 1995). Content of sleep onset mentation is believed to draw from episodic memory, as participants afterwards (once awake) tended to associate the content of sleep onset mentation with specific personal events (Cicogna, Cavallero, & Bosinelli, 1991;Cicogna et al, 1998).…”

Consciousness during Dreams

“…In our opinion, and in terms of mental processes, what may differ at the psychological level is the ''engagement amount'' of the cognitive system which is influenced by the modulation of the physiological background. This may explain the occurrence of dreams of different lengths and with different amounts of imagery, bizarreness, emotions, and so on (Antrobus, 1991(Antrobus, , 1999Cavallero et al, 1992;Cicogna et al, 1991Cicogna et al, , 1998Cicogna et al, , 2000Foulkes, 1985Foulkes, , 1996. Our viewpoint also includes the hypothesis of a single dream generator for both REM and NREM mental experiences.…”

Dreaming and the default network: A review, synthesis, and counterintuitive research proposal

“…Based on the similarity of dream reports after spontaneous morning awakenings from REM and NREM 2 (Cicogna, Natale, Occhionero, & Bosinelli, 1998), and the higher level of general brain activation in the early morning hours (Antrobus, Kondo, & Reinsel, 1995;Wamsley et al, 2007), it seems likely that the putative neural network for dreaming is active during NREM 2 at this time as well (Domhoff, 2011b(Domhoff, , pp. 1168(Domhoff, -1169, for a review of the evidence).…”