The classification of psychoactive substances (stimulants, entactogens, hallucinogens) in the frame of psychopharmacology was not worked on since the 1960s. Based on the authors empirical and theoretical research about the psychophysical correlates of waking altered states of consciousness, he lecture will present a recently developed new classification of psychoactive substances. Method: The...
INTRODUCTION: Pharmacological challenges with hallucinogens are used as models for psychosis in experimental research. The state induced by glutamate antagonists such as phencyclidine (PCP) is often considered as a more appropriate model of psychosis than the state induced by serotonergic hallucinogens such as lysergic acid diethylamide (LSD), psilocybin and N,N-dimethyltryptamine (DMT)....
Pharmacological challenges with hallucinogens are used as models for psychosis in experimental research. The state induced by glutamate antagonists such as phencyclidine (PCP) is often considered as a more appropriate model of psychosis than the state induced by serotonergic hallucinogens such as lysergic acid (LSD), psilocybin and dimethyltryptamine (DMT). However, so far, this question has...
The NMDA receptor antagonist ketamine produces transient dissociative and psychotic states in healthy humans that resemble symptoms of posttraumatic stress disorder (PTSD). Thus, symptoms induced by severe stress or ketamine might both be related to altered glutamatergic neurotransmission. Since ketamine is used as an analgesic and sedative in emergency care, it might be one factor exacerbating...
Patients with schizophrenia exhibit disturbances of orienting of attention. However, findings have been inconsistent. Hallucinogen challenges have been used as models for psychosis. The NMDA antagonist state resembles undifferentiated psychoses, whereas the 5-HT2A agonist state is considered as a model for psychoses with prominent positive symptoms. The aim of this study was to investigate...
: We want to call attention to a mint plant, called diviner's sage ( Salvia divinorum), originally used in shamanic ceremonies of the Mazatec Indians of Mexico. On numerous websites of the internet, this ancient herbal drug and its extracts are offered as a legal means of widening individual awareness. Regarding its dose-response relationship, the active ingredient, salvinorin A, is one of the...
Sigma (sigma) receptors, first defined as a subclass of opioid receptors, later confounded with the high affinity phencyclidine (PCP) binding sites, now are regarded as unique binding sites, distinct from opiate and PCP receptors, and related to higher brain function. The investigation of functional significance of sigma receptors in the brain has been hampered for many years by relative lack...
The APZ questionnaire was developed in order to explore hypotheses on ASCs. First -- in a series of 11 experiments using different induction methods on N = 393 healthy subjects -- the hypothesis was tested that ASCs have major dimensions in common irrespective of the mode of their induction. In the International Study on Altered States of Consciousness (ISASC) the external validity of the...
Recent research into the pharmacological mechanism of hallucinogens (LSD, psilocybin) and dissociative anesthetics (PCP, ketamine) suggest that multiple neurotransmitter systems are involved in drug-induced and possibly also in naturally occurring psychoses. Specifically, animal models suggest that a dysbalance between serotonin, glutamate, and dopamine in the limbic cortico-striato-thalamic...
The psychological, neuropsychological, and neurometabolic effects of the hallucinogenic agent mescaline were investigated in 12 normal male volunteers. Between 3 1/2 and 4 hours after drug intake, mescaline produced an acute psychotomimetic state, as measured by the BPRS and PDS-P. The APZ questionnaire revealed the specific effects of mescaline in the visual system. Neuropsychological effects...
Amphetamines, tryptamines, phencyclidines, tetrahydrocannabinol and substances of the ecstasy group are characterized as stimulants, hallucinogens and entactogens. The various effects of each group and their mode of action in different transmitter systems are described. 28 new compounds of the amphetamine and tryptamine series has been calculated, which exceed the hallucinogenic effects of...
Human experimental research with hallucinogenic drugs is potentially able to identify linking variables between the psycho(patho)logical conditions and neurobiological alterations involved in both pharmacologically induced and naturally occurring acute psychotic states. A number of methodological aspects should be considered when planning modern experimental studies with hallucinogenic drugs....
Drug models have been extensively used to study the pathophysiology of schizophrenia. While they provide good insight into the neurobiology of this disorder, they have several shortcomings, which if known, help in the interpretation of results. In this paper we will discuss these shortcomings in general, and in relation to the N-methyl D-aspartate antagonist model for schizophrenia. This model...
Cognitive impairments during psychotic episodes are assumed to be caused not only by one single putative classical neurotransmitter dysfunction but also to be due to an impaired equilibrium of the interaction between different neurobiological generators of cognitive processes. Here, the perceptual abnormalities induced by psychotogenic agents play a major role as tools for understanding model...
Systematic scientific interest in psychedelic substances has a tradition of about 100 years. Numerous human experimental studies have confirmed the existence of a common nucleus of experiences in hallucinogen-induced states and the acute stages of schizophrenic psychoses. However, the degree of resemblance between endogenous and drug-induced psychotic states has been an issue of controversial...
Monosymptomatic hypochondriasis, including delusional parasitosis and non-neurotic dysmorphophobia, are disorders which have been observed and recorded over the past century. These disorders occur commonly, and can be associated with significant morbidity. Once ominous of an extremely poor prognosis, there now exists a significant literature to suggest efficacy for pimozide. Taking LSD as a...
Stereoisomers have been used as tools to investigate the role of spatial (3-dimensional) features in neurochemical and behavioral effects of psychotropic drugs. Studies using enantiomers (optical isomers), geometrical isomers and semi-rigid molecules have shown that spatial features play a role in effects of antidepressant, antipsychotic, antiparkinsonian, and antianxiety drugs, as well as...
D-lysergic acid diethylamide (LSD) displays (1) the phenylethylamine pattern present in mescaline, cyclazocine and catecholamines and (2) the 4-substituted tryptamine structure of psilocybin which is a serotonin analog. Hence (a) Naloxone--a blocker of the LSD-like side effects of cyclazocine--should (and does) block effects of LSD, and (b) cross-tolerance may be present between LSD and...
There is a “natural” tendency to misjudge the position of the visual as compared to the gravitational vertical. A 160 µg/kg psilocybin-induced accentuation of this misjudgment in 16 college-age volunteers, and a further augmentation in their accentuated drug response after exposure to strong body distortion is reported.
Die Anwendung von Schwellendosen eines Halluzinogens (LSD-25, Psilocybin, CZ-74 und CEY-19) in der Psychotherapie erstreckt sich in der hier beschriebenen sog. psycholytischen Behandlung auf die Aktivierung unbewußten Konfliktmaterials in einer besonders intensiv erlebbaren und für den Probanden sinnträchtigen Weise. Die chemisch-pharmakologische Eigenwirkung der Halluzinogene kann über ihrer...
The use of LSD in the treatment of alcoholism has led to many claims concerning the drug's efficacy. Efforts to verify these reports in controlled studies have been difficult because of the unique effects of LSD. Despite this formidable methodological obstacle a number of investigations have been carried out. A critique of these is presented followed by our own research experience in a...
Using apparent fronto-parallel plane (AFP) monitoring techniques, the relative stability of the abathic plane, i.e., Euclidean visual space, was investigated in 16 volunteers with a median age of 23.5 years under 160 µg/kg psilocybin-induced ergotropic arousal. Handwriting area and pressure were also measured in the same subjects.
Obschon Haschisch und Marihuana oft synonym verwendet werden, ist unter Haschisch im engeren Sinn die pharmakologisch hochwirksame Harzsubstanz der Hanfpflanze (Cannabis sativa) zu verstehen, während Marihuana auch die schwächer wirksameren Blätter, Stengel und Blüten von Cannabis bezeichnet. Die für den Haschischrausch verantwortlichen Stoffe des Hanfs gehören zu den Tetrahydrocannabinolen...
The influence of personality structure on the stability of perceptual performance, specifically the degree of reproducibility under hypnotic induction of the psilocybinproduced lowering of spatial distortion thresholds, was investigated in two "variable" and two "stable" psilocybin reactors, that is, subjects who displayed variable and stable MMPI profiles under both control conditions and the...
Autonomic, perceptual, and behavioral changes induced by 160 µg/kg psilocybin were studied in a homogenous sample of 15 self-selected College educated male and female volunteers. The subjects were rank ordered as to the extent of drug-induced psychopathology using their Minnesota Multiphasic Personality Inventory pre-drug to drug peak differences scores. Extent of variability on simple...