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Jiřı́ Wackermann

Institute for Frontier Areas of Psychology and Mental Health

3 papers in the library · 584 citations · publishing 2005-2013

Papers

Psychobiology of Altered States of Consciousness.

Psychological Bulletin January 1, 2005 Dieter Vaitl, Niels Birbaumer, John Gruzelier et al. 446 citations

Altered states of consciousness (ASC) can occur spontaneously, be evoked by physical or physiological stimulation, induced by psychological means, or caused by diseases. Psychological and neurobiological approaches reveal four dimensions characterizing ASC: activation, awareness span, self-awareness, and sensory dynamics. Neurophysiologically, different states of consciousness arise from compromised brain structure, transient changes in brain dynamics (disconnectivity), and neurochemical and metabolic processes. Environmental stimuli, mental practices, and self-control techniques can also temporarily alter brain functioning and conscious experience.

DOI: 10.1037/0033-2909.131.1.98 Neurochemical Behavioral neuroscience Cognitive psychology Neurophysiology +4

Effects of varied doses of psilocybin on time interval reproduction in human subjects

Neuroscience Letters February 13, 2008 Jiřı́ Wackermann, Marc Wittmann, Felix Hasler et al. 95 citations

Psilocybin, a hallucinogenic substance, alters the internal representation of time by increasing the loss rate of the internal duration representation. In two double-blind, placebo-controlled experiments—one with 12 subjects receiving graded doses and another with 9 subjects receiving a very low dose—participants repeatedly reproduced time intervals between 1.5 and 5 seconds. The parameter kappa from the 'dual klepsydra' model was used to assess effects. At 90 minutes after intake, psilocybin significantly increased kappa, indicating a higher loss rate of internal time representation. These findings may relate to qualitative changes in subjective time during altered states of consciousness.

DOI: 10.1016/j.neulet.2008.02.006 Psilocybin Hallucinogen Placebo Kappa +4