EEG correlates of multimodal ganzfeld induced hallucinatory imagery

A phenomenology of meditation-induced light experiences: traditional buddhist and neurobiological perspectives

“…Perceptual isolation refers to exposure to homogenous, invariant, or unstructured stimuli (Wackermann et al, 2002,2008; Pütz et al, 2006; Lloyd et al, 2012). While sensory input is not technically absent in perceptual isolation, the monotony leads to habituation where input is “filtered out,” which can mimic the effects of decreased input of sensory deprivation (Pütz et al, 2006).…”

“…While sensory input is not technically absent in perceptual isolation, the monotony leads to habituation where input is “filtered out,” which can mimic the effects of decreased input of sensory deprivation (Pütz et al, 2006). …”

“…However, it is insufficient to rely solely upon traditional textual sources as a means of investigating the cause or significance of these phenomena. For this reason, our qualitative data are considered in relation to scientific research on sensory deprivation (e.g., Zubek et al, 1961; Zuckerman, 1969; Merabet et al, 2004), perceptual isolation (homogenous stimuli; e.g., Wackermann et al, 2002,2008; Pütz et al, 2006; Lloyd et al, 2012), and clinical disorders of the visual system (e.g., Santhouse et al, 2000; Wilkinson, 2004; Vukicevic and Fitzmaurice, 2008; Ffytche et al, 2010). These studies, discussed below, also provide evidence in support of the hypothesis that certain contemplative practices – especially those that deliberately decrease social, kinesthetic, and sensory stimulation and emphasize focused attention – have perceptual and cognitive outcomes similar to sensory deprivation.…”

Motivation, emotion, and their inhibitory control mirrored in brain oscillations

“…Babiloni et al, 2004a;Hwang et al, 2005;Klimesch et al, 1999;Krause et al, 1999;Putz et al, 2005). In a series of reviews, Klimesch (1996Klimesch ( , 1997Klimesch ( , 1999) discussed experimental findings supporting the hypothesis that short-term (episodic) memory demands lead to synchronization in the theta band, whereas long-term (semantic) memory demands lead to a task-specific desynchronization in the upper alpha band.…”

On the meaning and interpretation of global descriptors of brain electrical activity. Including a reply to X. Pei et al.

“…To investigate the relationship between Ω and Ω R in real brain electrical data, the measures were evaluated for 19-channel EEG (system 10/20) recorded from subjects in a relaxed waking state, exposed to multi-modal ganzfeld stimulation (Pütz et al, 2006). Complexity measures were calculated on two-seconds (512 samples) data epochs that had been visuo-manually selected as artefact-free, after transformation to the average reference.…”