Purpose: We sought brain activity that predicts visual consciousness. Methods: We used electroencephalography (EEG) to measure brain activity to a 1000-ms display of sine-wave gratings, oriented vertically in one eye and horizontally in the other. This display yields binocular rivalry: irregular alternations in visual consciousness between the images viewed by the eyes. We replaced both...
Summary: We have investigated the ability of the 5HT2‐receptor antagonist ketanserin to affect the hyperthermia produced by methylenedioxymethamphetamine (MDMA) in conscious mice and examined whether α1‐adrenoceptor antagonist actions are involved. Mice were implanted with intra‐abdominal temperature probes under anaesthesia and allowed 2 weeks recovery. MDMA (20 mg kg−1) was administered...
Abstract The psychedelic experience has been reported since antiquity, but there is relatively little known about the underlying neural mechanisms. A recent neuroimaging study on psilocybin revealed a pattern of decreased cerebral blood flow and functional disconnections that is surprisingly similar to that caused by various anesthetics. In this article, the authors review historical examples...
INTRODUCTION: General anesthesia induces unconsciousness along with functional changes in brain networks. Considering the essential role of hub structures for efficient information transmission, the authors hypothesized that anesthetics have an effect on the hub structure of functional brain networks. METHODS: Graph theoretical network analysis was carried out to study the network properties of...
Numerous plant species are used throughout the world to achieve the modified states of conscientiousness. Some of them have been used for the therapeutic purposes, such as Mimosa tenuiflora (Willd) Poir. (family Mimosaceae) known as "jurema-preta", an hallucinogenic plant traditionally used for curing and divination by the Indians of northeastern Brazil. In this review, several aspects of the...
We present Activity Analysis as a new method for the quantification of subjective reports of altered states of consciousness with regard to the indicated level of simulated motor activity. Empirical linguistic activity analysis was conducted with dream reports conceived immediately after EEG-controlled periods of hypnagogic hallucinations and REM-sleep in the sleep laboratory. Reports of...
General anesthesia significantly alters brain network connectivity. Graph-theoretical analysis has been used extensively to study static brain networks but may be limited in the study of rapidly changing brain connectivity during induction of or recovery from general anesthesia. Here we introduce a novel method to study the temporal evolution of network modules in the brain. We recorded...
This chapter considers how psychedelic substances affect consciousness, using the lens of a transpersonal approach to psychology. Transpersonal psychology's point of view is especially suitable to grapple with this question due not only to its continuing interest in altered states of consciousness, but also to its long-standing relationship with psychedelic research. Mainstream psychology has...
Besides stimulants and hallucinogens, whose psychotropic effects are shared by many structurally related molecules exhibiting different efficacies and potencies in humans, the phenylisopropylamine MDMA (3,4-methylenedioxymethamphetamine, XTC, "Ecstasy") is the prototypical representative of a separate class of psychotropic substance, able to elicit the so-called entactogenic syndrome in healthy...
Exotic experiences such as the sensing of another consciousness or the detachment of consciousness from the body are occasionally reported by individuals with partial seizures from a temporal lobe focus. The experiences display the characteristics of Hughlings Jackson's "parasitic consciousness". We have hypothesized that these experiences are encouraged by slight discrepancies in hemispheric...