A Ganzfeld, a homogeneous visual field without focal points, induces altered states of consciousness and immersive full-body experiences, including bodily effects. Using eye-tracking, EEG, interviews, and questionnaires, the study identified two cognitive processing types: a perceptually grounded type with inward- or outward-directed focus, and an abstract type with introspective focus and meditative experiences. Perceptual decays were accompanied by decreased eye movements and increased theta activity preceding them, suggesting a link to mind blanking. Decays also showed more alpha activity, associated with attenuated sensory processing and reduced external engagement. These findings provide a comprehensive understanding of the rich Ganzfeld experience.
A Ganzfeld—a homogeneous, unstructured visual field—induces visual hallucinations and characteristic decays of color and brightness. This paper synthesizes literature from the 1930s onward to clarify terminology for these decaying experiences. Using a custom-built Ganzfeld space to avoid the confinement of translucent goggles, the authors employed a multi-method approach combining quantitative and qualitative measures. They identified three distinct types of decays: 'fade-out', 'black-out', and 'blank-out', reporting their prevalence and qualitative features. The work also examines the role of eye movements and blinks on experienced phenomena, providing groundwork for studying Ganzfeld experiences in relation to consciousness and neural correlates.