The Dream Catcher experiment: blinded analyses failed to detect markers of dreaming consciousness in EEG spectral power.
William Wong, Valdas Noreika, Levente Móró, Antti Revonsuo, Jennifer Windt, Katja Valli, Naotsugu Tsuchiya
Neuroscience of Consciousness 2020 DOI: 10.1093/nc/niaa006 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Experimental study with blinded classification Peer reviewed |
|---|---|
| Sample size | 9 |
| Population | Human participants during sleep |
| Topics | Dreaming |
| Keywords | EEG Correlates Nrem sleep Dreams Unconsciousness Unsupervised machine learning |
| Citations | 35 |
| Key findings | EEG spectral power features could not be used to classify dreamful versus dreamless sleep above chance level. |
Abstract
The Dream Catcher test defines the criteria for a genuine discovery of the neural constituents of phenomenal consciousness. Passing the test implies that some patterns of purely brain-based data directly correspond to the subjective features of phenomenal experience, which would help to bridge the explanatory gap between consciousness and brain. Here, we conducted the Dream Catcher test for the first time in a step-wise and simplified form, capturing its core idea. The Dream Catcher experiment involved a Data Team, which measured participants' brain activity during sleep and collected dream reports, and a blinded Analysis Team, which was challenged to predict, based solely on brain measurements, whether or not a participant had a dream experience. Using a serial-awakening paradigm, the Data Team prepared 54 1-min polysomnograms of non-rapid eye movement sleep-27 of dreamful sleep and 27 of dreamless sleep (three of each condition from each of the nine participants)-redacting from them all associated participant and dream information. The Analysis Team attempted to classify each recording as either dreamless or dreamful using an unsupervised machine learning classifier, based on hypothesis-driven, extracted features of electroencephalography (EEG) spectral power and electrode location. The procedure was repeated over five iterations with a gradual removal of blindness. At no level of blindness did the Analysis Team perform significantly better than chance, suggesting that EEG spectral power could not be utilized to detect signatures specific to phenomenal consciousness in these data. This study marks the first step towards realizing the Dream Catcher test in practice.
Comparable studies
Other experimental studies on dreaming, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Lucid Dreaming Verified by Volitional Communication during Rem Sleep Selected subjects proficient in lucid dreaming | 1981 | Experimental study | n = 5 |
| Incorporation of concern- and nonconcern-related verbal stimuli into dream content. Seven male subjects studied during sleep Stages 2 and REM | 1981 | Experimental study | n = 7 |
| Lucid Dreaming and Alpha Activity: A Preliminary Report Good dream recallers | 1982 | Experimental study | n = 10 |
| Lucid dreaming during NREM sleep: Two case reports | 2012 | Sleep laboratory study | |
| Flying dreams stimulated by an immersive virtual reality task. Participants who underwent VR-flying and a morning nap | 2020 | Experimental study | n = 137 |
Citations in the library
Cited by 19
- Theories of consciousness. Nature Reviews Neuroscience July 1, 2022
- Consciousness among delta waves: a paradox? Brain March 6, 2021
- What about dreams? State of the art and open questions Journal of Sleep Research April 13, 2022
- How deep is the rift between conscious states in sleep and wakefulness? Spontaneous experience over the sleep–wake cycle Philosophical transactions of the Royal Society of London. Series B, Biological sciences December 13, 2020
- EEG Lempel-Ziv complexity varies with sleep stage, but does not seem to track dream experience. Frontiers in Human Neuroscience 2022
and 14 more in the library
Cites 29
- An information integration theory of consciousness BMC Neuroscience November 2, 2004
- Consciousness as Integrated Information: a Provisional Manifesto Biological Bulletin December 1, 2008
- No-Report Paradigms: Extracting the True Neural Correlates of Consciousness Trends in Cognitive Sciences November 13, 2015
- The spectral exponent of the resting EEG indexes the presence of consciousness during unresponsiveness induced by propofol, xenon, and ketamine Neuroimage January 11, 2019
- Neural Correlates of Dream Lucidity Obtained from Contrasting Lucid versus Non-Lucid REM Sleep: A Combined EEG/fMRI Case Study Sleep June 29, 2012
and 24 more in the library