Neuronal Correlates of Altered States of Consciousness

Functional neuroimaging may be useful in the diagnosis and characterization of early schizophrenia. However, little is known about how the subjectively experienced alterations in consciousness and perception are related with objective neuroimaging measures. The present study explores the association of subjective alterations and objective imaging findings and will inform us on the neuronal correlates of psychotic states and whether subjective alterations in perception translate into neuronal activation patterns that can be objectively measured in a brain scanner. Therefore, alterations in consciousness will be assessed in 20 healthy subjects using a random order 2-period (normal and altered state of consciousness) cross-over design. Alterations in consciousness will be induced by the hallucinogenic 5-hydroxytryptamine (HT)2A receptor agonist (5-HT2A) receptor agonist lysergic acid diethylamide (LSD).