Fully immersed: State absorption and electrophysiological effects of the OVO Whole-Body Perceptual Deprivation chamber

Absorption, the ability to highly focus attention, as well as openness to self-altering experiences, is an important psychological construct, closely related to deep-meditation states and other altered states of consciousness. Yet, little is known about the electrophysiological profile of states of absorption, possibly due to the difficulty to induce this state in the lab. While most studies have used a visual Ganzfeld (homogeneous perceptual field), here we use a novel technique of full immersion-the OVO Whole-Body Perceptual Deprivation (OVO-WBPD) chamber, which is an altered sensory environment in the form of a human-sized egg. Consequently, the aims of the current study were to investigate whether the OVO-WBPD chamber induces state absorption, using first-person reports, as well as to examine electrophysiological change following immersion in this altered sensory environment. Fourteen participants volunteered to participate in the study. Trait absorption was measured using the Tellegen Absorption Scale (TAS). State absorption was assessed by analyzing the content of the subjective reports, using sub-categories of the absorption construct (e.g., synesthesia). EEG was measured before and during a 20-min OVO-WBPD experience. Using exact low-resolution brain electromagnetic tomography (eLORETA), we analyzed change in oscillatory EEG activity and localized the generators of the scalp EEG power spectra following the OVO-WBPD. Our results show that OVO-WBPD immersion leads to a state of absorption in all participants. We also report significant increased oscillatory activity in the delta and beta bands, in the left inferior frontal cortex, with a peak in the sub-lobar of the left insula. In addition, a positive correlation was found between change in delta activity and trait absorption. The results are discussed in light of other meditative practices and altered states of consciousness.