Human Brain Mapping
August 21, 2020
Lukasz Smigielski, Michael Kometer, Milan Scheidegger et al.
42 citations
A placebo-controlled, double-blind experiment with 17 participants found that psilocybin, a serotonin receptor agonist, alters self-perception by disrupting the brain's ability to distinguish between self- and other-related stimuli. Participants performed a verbal self-monitoring task while brain activity was recorded. Psilocybin reduced accuracy in identifying whether auditory feedback was their own voice or another's, and it eliminated the typical difference in electrical brain patterns (P300) between self and other stimuli. This effect was linked to changes in the anterior cingulate and insular cortex. The strength of this brain change correlated with feelings of unity and altered meaning. The findings suggest that serotonin signaling modulates how the brain processes self-referential information, offering insight into self-disturbances in mental health conditions.
Brain Topography
March 1, 2024
Sarah Diezig, Simone Denzer, Peter Achermann et al.
19 citations
During the transition to sleep, reflective awareness—the ability to recognize experiences as internally generated—breaks down before phenomenal awareness, the basic experience itself, fades. Dream-like experiences, characterized by uncontrolled thinking and perceptual images mistaken as real, are associated with an inverse relationship between cognitive effects and physiological activation in the brain. In 45 healthy young subjects, EEG microstate analysis showed that dream-like experiences correlated with increased presence of a microstate sourced in the superior and middle frontal gyrus and precuneus, and decreased presence of a microstate linked to higher-order visual areas. This suggests disengagement of cognitive control systems mediated by specific inhibitory microstates.
European Journal of Neuroscience
September 11, 2024
Simone Denzer, Sarah Diezig, Peter Achermann et al.
6 citations
Monitoring whether an experience is real or not is crucial for everyday functioning, but this reality monitoring can go awry during dreams or hallucinations. To investigate brain processes underlying perceptual reality monitoring—the online assessment of reality during an experience—healthy young participants were immersed in a highly naturalistic virtual reality environment containing either realistic or dream-like bizarre elements. Dream-like bizarreness altered subjective experiences of reality and bizarreness and increased the contribution of a specific EEG microstate, labeled C'. This microstate is linked to suspending disbelief, or suppressing mismatches that seem bizarre. The findings suggest that prefrontal meta-conscious control processes are important for perceptual reality monitoring.
Schizophrenia Research
June 2, 2025
Maria Chiara Piani, Martin Jandl, Thomas Koenig et al.
3 citations
Self-disorders, which disrupt the basic sense of being a conscious subject, are central to schizophrenia spectrum disorders. Using 7 Tesla fMRI, 27 patients and 32 healthy controls performed a trait-judgment task probing pre-reflective and reflective self-experience. Greater severity of self-disorders correlated with reduced activity in the rostral posterior cingulate cortex during the pre-reflective component. During reflective self-experience, healthy controls showed bilateral frontopolar cortex activation, while patients engaged the left caudate, right frontopolar cortex, and left language area, suggesting patients rely more on analytical networks and deeper brain structures rather than the interoceptive processes typical of healthy controls.
Consciousness and Cognition
April 13, 2026
Xinlin Wang, Emma Peters, Johannes Strelen et al.
During lucid dreaming, the dreamer is aware they are dreaming. To identify brain network activity linked to this conscious experience, 39 sleep recordings (lucid vs. non-lucid REM sleep) from 8 lucid dreamers were analyzed using EEG microstate analysis. Microstates A and G dominated during lucid REM, while microstates B, C, and D dominated during non-lucid REM. These microstates were associated with emotional processing (A), visual processing (B), salience network activity (C), executive functions (D), and the default mode network (G). Results suggest lucidity involves increased self-visualization, metacognition, and executive processing, with decreased emotional processing and default mode network activity, indicating distinct network dynamics in lucid REM sleep.
International journal of psychophysiology : official journal of the International Organization of Psychophysiology
June 1, 2023
Sarah Diezig, Melissa Spaar, Simone Denzer et al.
The ability to organize self-generated thought into coherent, meaningful semantic representations is a central aspect of human cognition and undergoes regular alterations throughout the day. To investigate whether changes in semantic processing might explain the loss of coherence, logic, and voluntary control over thinking typically accompanying the transition to sleep, N400 evoked potentials were recorded from 44 healthy subjects. Auditory word pairs with varying semantic distance were presented while subjects were allowed to fall asleep. Semantic distance reliably elicited an N400, and lower wakefulness levels were associated with increased frontal negativity. Contrary to the initial hypothesis, the results showed an increased N400 effect with decreasing wakefulness, suggesting that semantic processes alone may not explain diminished thought control during sleep onset.
Social Neuroscience
June 1, 2022
Yoshija Walter, Thomas Koenig
Religious experiences during worship are associated with large-scale brain activation patterns involving the auditory network, salience network, and default mode network, but not the network for multisensory integration. In 60 evangelical Christians who continuously rated their sense of God's presence while listening to songs, EEG microstate analysis revealed these neural correlates.