Objective: An experiment was conducted to determine the effects of chanting the maha mantra on stress, depression, and the three gunas—sattva (enlightenment), rajas (passion), and tamas (inertia)—described in the Vedas as the basis of human psychology. Primary hypotheses of the study were that the maha mantra group would increase sattva and decrease stress, depression, rajas, and tamas...
Functional dopaminergic hyperactivity is a key feature of schizophrenia. Etiology of this dopaminergic hyperactivity, however, is unknown. We have recently demonstrated that subchronic phencyclidine (PCP) treatment in rodents induces striatal dopaminergic hyperactivity similar to that observed in schizophrenia. The present study investigates the ability of PCP to potentiate amphetamine-induced...
The role of the N-methyl-D-aspartate (NMDA) neurotransmitter system in relation to psychoses is not completely understood, but represent a challenge in neurobiological research. The psychotic states induced by NMDA antagonists such as phencyclidine and ketamine have been described as being most similar to schizophrenia and the NMDA system has been implicated in the pathogenesis of...
Previously the NMDA (N-methyl-D-aspartate) receptor (NMDAR) antagonist ketamine was shown to disrupt generation of the auditory event-related potential (ERP) mismatch negativity (MMN) and the performance of an 'AX'-type continuous performance test (AX-CPT)--measures of auditory and visual context-dependent information processing--in a similar manner as observed in schizophrenia. This...
Ibogaine is a naturally occurring indole alkaloid, found in a variety of African shrubsof the Tabernathe genus (Obach, Pablo, and Mash, 1998). The root of the Tabernathe ibogaplant (also known as eboga) is the most frequently cited source of ibogaine, and this plantcontains 11 other known psychoactive constituents (Popik, and Skolnick, 1999). Chemically,ibogaine is classified as a tryptamine,...
The issue of whether an association exists between cannabis and psychosis exists, and why, has received considerable attention in recent years (Hall, 1998; Mueser et al. 1998; Blanchard et al. 2000; Degenhardt & Hall, 2002). There are probably a number of reasons for the sustained interest. First, psychotic disorders such as schizophrenia are often chronic or recurring (Mason et al. 1996), are...
During the waking state, a late component of the auditory event-related potential, P300, is elicited when subjects detect a rare 'target' stimulus. It is usually not elicited when subjects either ignore or fail to detect the stimulus. The presence of P300 is therefore thought to reflect conscious processing of the stimulus. Since P300 has been shown to be an attention-dependent cognitive...
RationaleAyahuasca, a South American psychotropic plant tea, combines the psychedelic agent and 5-HT(2A/2C) agonist N, N-dimethyltryptamine (DMT) with beta-carboline alkaloids showing monoamine oxidase-inhibiting properties. Current human research with psychedelics and entactogens has explored the possibility that drugs displaying agonist activity at the 5-HT(2A/2C) sites temporally disrupt...
The hallucinogen d-lysergic acid diethylamide (d-LSD) evokes dramatic somatic and psychological effects. In order to analyze the neural activation induced by this unique psychoactive drug, we tested the hypothesis that expression of the immediate-early gene product c-Fos is induced in specific regions of the rat forebrain by a relatively low, behaviorally active, dose of d-LSD (0.16 mg/kg,...
This article presents data from two avenues of marijuana research. First, the author shows that daily marijuana smoking in healthy individuals produces dependence, as demonstrated by withdrawal symptoms such as increased irritability and depression and decreased food intake. In addition, two antidepressant medications were evaluated to assess their potential effectiveness in the treatment of...