Disrupted integration of sensory stimuli with information about the movement of the body as a mechanism explaining LSD-induced experience.

Summary

LSD induces specific sensory experiences characterized by illusory movement and bodily sensations, such as floating and out-of-body experiences. The study suggests that LSD's stimulation of serotonergic 5-HT2a receptors disrupts how the brain integrates sensory information with body movement, leading to these perceptions. Despite understanding the molecular mechanisms involved, the exact trigger for these unique experiences remains unclear.

Study at a glance

Abstract

LSD (lysergic acid diethylamide) is a model psychedelic drug used to study mechanism underlying the effects induced by hallucinogens. However, despite advanced knowledge about molecular mechanism responsible for the effects induced by LSD and other related substances acting at serotonergic 5-HT2a receptors, we still do not understand how these drugs trigger specific sensory experiences. LSD-induced experience is characterised by perception of movement in the environment and by presence of various bodily sensations such as floating in space, merging into surroundings and movement out of the physical body (the out-of-body experience). It means that a large part of the experience induced by the LSD can be simplified to the illusory movement that can be attributed to the self or to external objects. The phenomenology of the LSD-induced experience has been combined with the fact that serotonergic neurons provide all major parts of the brain with information about the level of tonic motor activity, occurrence of external stimuli and the execution of orienting responses. Therefore, it has been proposed that LSD-induced stimulation of 5-HT2a receptors disrupts the integration of the sensory stimuli with information about the movement of the body leading to perception of illusory movement.