Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Jan:97:103247.
doi: 10.1016/j.concog.2021.103247. Epub 2021 Dec 2.

Episodic thought distinguishes spontaneous cognition in waking from REM and NREM sleep

Benjamin Baird  1 , Mariel Kalkach Aparicio  2 , Tariq Alauddin  2 , Brady Riedner  2 , Melanie Boly  3 , Giulio Tononi  2
Affiliations

Episodic thought distinguishes spontaneous cognition in waking from REM and NREM sleep

Benjamin Baird et al. Conscious Cogn. 2022 Jan.

Abstract

Evidence suggests continuity between cognition in waking and sleeping states. However, one type of cognition that may differ is episodic thoughts of the past and future. The current study investigated this across waking, NREM sleep and REM sleep. We analyzed thought reports obtained from a large sample of individuals (N = 138) who underwent experience-sampling during wakefulness as well as serial awakenings in sleep. Our data suggest that while episodic thoughts are common during waking spontaneous thought, episodic thoughts of both the past and the future rarely occur in either N2 or REM sleep. Moreover, replicating previous findings, episodic thoughts during wakefulness exhibit a strong prospective bias and frequently involve autobiographical planning. Together, these results suggest that the occurrence of spontaneous episodic thoughts differs substantially across waking and dreaming sleep states. We suggest that this points to a difference in the way that human consciousness is typically experienced across the sleep-wake cycle.

Keywords: Autonoetic consciousness; Dreaming; Episodic future thought; Episodic memory; Mental time travel; Mind-wandering; Spontaneous thought.

PubMed Disclaimer

Figures

Figure 1.
Figure 1.
Proportion of episodic past and future thoughts across waking spontaneous thought, NREM and REM dreaming sleep states. Episodic thoughts are common during waking spontaneous thought and exhibit a strong prospective bias. In contrast, episodic thoughts of both the past and the future rarely occur in both N2 sleep and REM sleep.
Figure 2.
Figure 2.
Percentage of past and future thoughts involving self, goal and both self and goal-related content of spontaneous thoughts during wakefulness. Both past and future thoughts frequently involve the self, but future thought also frequently involves goal-directed operations on self-relevant information. Examples from each category are shown below for thoughts of the past and future, respectively.
See this image and copyright information in PMC

References

    1. Baird B, Mota-Rolim SA, & Dresler M (2019). The cognitive neuroscience of lucid dreaming. Neuroscience & Biobehavioral Reviews, 100, 305–323. - PMC - PubMed
    1. Baird B, Smallwood J, Lutz A, & Schooler JW (2014). The decoupled mind: mind-wandering disrupts cortical phase-locking to perceptual events. Journal of Cognitive Neuroscience, 26(11), 2596–2607. - PubMed
    1. Baird B, Smallwood J, & Schooler JW (2011). Back to the future: autobiographical planning and the functionality of mind-wandering. Consciousness and Cognition, 20(4), 1604–1611. - PubMed
    1. Bates D, Mächler M, Bolker B, & Walker S (2014). Fitting linear mixed-effects models using lme4. arXiv preprint arXiv:1406.5823.
    1. Baumeister RF, & Masicampo E (2010). Conscious thought is for facilitating social and cultural interactions: How mental simulations serve the animal–culture interface. Psychological review, 117(3), 945. - PubMed

Publication types

LinkOut - more resources