A reduced level of consciousness affects non-conscious processes
Aurelie Fontan, Lenita Lindgren, Tiziana Pedale, Camilla Brorsson, Fredrik Bergström, Johan Eriksson
bioRxiv Preprint Server November 10, 2020 preprint DOI: 10.1101/2020.11.10.376483 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Experimental study |
|---|---|
| Intervention | Propofol sedation |
| Key findings | Level and content of consciousness are separate phenomena, as sedation affected non-conscious processes as much as conscious ones. |
Abstract
Being conscious is a profound aspect of human existence, and understanding its function and its inception is considered one of the truly grand scientific challenges. However, the nature of consciousness remains enigmatic, to a large part because “being conscious” can refer to both the content (phenomenology) and the level (arousal) of consciousness, and how these different aspects are related remains unclear. To empirically assess the relation between level and content of consciousness, we manipulated these two aspects by presenting stimuli consciously or non-consciously and by using Propofol sedation, while brain activity was measured using fMRI. We observed that sedation greatly affected non-conscious processes, which starkly contrasts the notion that anesthetics selectively reduce consciousness. Our findings reveal that level and content of consciousness are separate phenomena, and imply that one may need to reconsider what “being conscious” means.