Frontiers in integrative neuroscience
January 1, 2014
Klaus M Stiefel, Alistair Merrifield, Alex O Holcombe
59 citations
The claustrum, a brain region rich in κ-opioid receptors, may serve as a conductor for certain aspects of higher-order integration of brain activity, but not for all sensory integration. The plant Salvia divinorum and its active ingredient salvinorin A, a κ-opioid receptor agonist, produce consciousness-altering effects that disrupt certain facets of consciousness more than LSD does. This disruption likely results from κ-opioid receptor mediated inhibition of the claustrum and deep cortical layers, especially prefrontal areas. The findings support the theory that the claustrum plays a key role in consciousness, while auditory and visual signal integration relies more on other areas like parietal cortex and the pulvinar.
Frontiers in integrative neuroscience
January 1, 2024
Alexandra Lopes, Rute Sampaio, Isaura Tavares
3 citations
Pain is influenced by psychological and social factors, including the placebo effect. Mindfulness-based interventions (MBIs) reduce pain, but how they work is not fully understood. This systematic review of 19 studies (10 on acute pain, 9 on chronic pain) examined whether placebo effects and expectations contribute to MBIs' pain relief. Only six studies measured placebo effects related to a drug, not the MBI itself. The few studies that did focus on MBIs suggest that placebo and expectations play a role in their effects on pain. Although these factors are often discussed, they are rarely measured in experiments. The review concludes that placebo and expectancy effects clearly contribute to MBIs' pain relief, and future studies should routinely measure them.
Frontiers in integrative neuroscience
January 1, 2021
Ege Tekgün, Burak Erdeniz
3 citations
Out-of-body experiences (OBEs) can be simulated in virtual reality, but how body orientation affects these illusions is unclear. In a within-group experiment, 30 participants embodied a full-body virtual avatar from a first-person perspective, then experienced a virtual OBE by switching to a third-person view raised 14 meters above the avatar. Participants performed a mental ball dropping (MBD) task at baseline and during the OBE. MBD durations were longer when participants were lying supine compared to standing. Subjective reports confirmed previous virtual OBE findings, but body ownership did not differ between the two postures. The results contribute to understanding the vestibular system and time perception during OBEs.
Frontiers in integrative neuroscience
January 1, 2026
Alfredo López Parra
Consciousness research lacks an explicit account of the temporal constraints needed for information to become consciously accessible. This paper proposes that temporal integration is a biologically invariant constraint operating across multiple scales, from cells to organisms. Drawing on evidence of memory in non-neuronal cells, the authors introduce a minimal bioelectrical/biochemical temporal window (ΔT_b) governing cellular information consolidation, which may contribute to organismic basal coherence (γ) through bioelectric and autonomic mechanisms. The Libet paradigm is reinterpreted as reflecting necessary delays for multilevel integration rather than evidence against agency. The pathway from cellular temporal integration to autonomic coherence is classified as mechanistically plausible, requiring empirical validation.