humulene and Schizotypal-Personality-Disorder

Cannabis consumption can cause abuse and dependence and increase risk of developing psychiatric and somatic disorders. Several literature reviews explored the link between cannabis consumption and schizophrenia but none summarized the rich literature on cannabis and psychometric schizotypy. The aim of our review is to synthesize data from studies that explored the association between cannabis consumption and schizoptypal dimensions. A systematic review of the literature and, when needed, contact with the authors, allowed us to gather data from 29 cross-sectional studies. We compared schizotypy scores between subjects that never used cannabis and subjects that used it at least once ("never vs. ever") and between current users and subjects that do not use cannabis currently ("current vs. other"). We conducted separate analyses for total schizotypy score and each of the three classical schizotypal dimensions (positive, negative, disorganized). For all eight comparisons, the cannabis group ("ever" or "current") had higher schizotypy scores. Differences were in the small or medium range and, with the exception of the negative score in the current vs. other comparison, statistically significant. Cannabis consumption is associated with increased schizotypal traits. More research, using different approaches (e.g. longitudinal studies) is needed to explore the cause of this association.

Topics: Cannabis; Cross-Sectional Studies; Female; Humans; Marijuana Abuse; Marijuana Smoking; Psychometrics; Schizotypal Personality Disorder

Schizotypy and its associated features-negative schizotypy, disorganization, and positive schizotypy-are correlated with increased cannabis use. Yet, it is unclear whether cannabis users with schizotypy are at greater risk of developing cannabis problems. Individuals with elevated schizotypy may be particularly vulnerable to cannabis problems. It is important to understand this association given the unknown harms of chronic cannabis use. Data for these analyses were drawn from a larger investigation of cannabis use in adult romantic relationships. Participants were community adults (N = 366; M Age = 24.6, SD = 3.1) who reported regular use of cannabis. Participants completed baseline surveys measuring cannabis use frequency, problems, and schizotypy. Follow-up assessments of cannabis problems and frequency were completed 4-, 7- and 10-months post-baseline. Multiple regression was used to test the effect of schizotypy-measured using the Schizotypal Personality Questionnaire-Brief (SPQ-B, Raine & Benishay, 1995)-on cannabis use problems controlling for 30-day cannabis use. At baseline, disorganization and positive schizotypy were associated with cannabis use, primarily for women. Results revealed that with cannabis use frequency in the model, the Disorganization subscale of the SPQ-B predicted cannabis problems at baseline and all 3 follow-up assessments. Results are consistent with research suggesting that those exhibiting odd behaviors report more problematic cannabis use. Future research may further this line of inquiry with a focus on longitudinal, reciprocal relationships among schizotypy features, cannabis use, and cannabis problems.

Topics: Adult; Cannabis; Female; Humans; Personality; Personality Inventory; Schizotypal Personality Disorder; Surveys and Questionnaires; Young Adult

Cannabis can induce acute psychotic symptoms in healthy individuals and exacerbate pre-existing psychotic symptoms in patients with schizophrenia. Inappropriate salience allocation is hypothesised to be central to the association between dopamine dysregulation and psychotic symptoms. This study examined whether cannabis use is associated with self-reported salience dysfunction and schizotypal symptoms in a non-clinical population. 910 University students completed the following questionnaire battery: the cannabis experience questionnaire modified version (CEQmv); schizotypal personality questionnaire (SPQ); community assessment of psychic experience (CAPE); aberrant salience inventory (ASI). Mediation analysis was used to test whether aberrant salience mediated the relationship between cannabis use and schizotypal traits. Both frequent cannabis consumption during the previous year and ASI score predicted variation across selected positive and disorganised SPQ subscales. However, for the SPQ subscales 'ideas of reference' and 'odd beliefs', mediation analysis revealed that with the addition of ASI score as a mediating variable, current cannabis use no longer predicted scores on these subscales. Similarly, cannabis use frequency predicted higher total SPQ as well as specific Positive and Disorganised subscale scores, but ASI score as a mediating variable removed the significant predictive relationship between frequent cannabis use and 'odd beliefs', 'ideas of reference', 'unusual perceptual experiences', 'odd speech', and total SPQ scores. In summary, cannabis use was associated with increased psychometric schizotypy and aberrant salience. Using self-report measures in a non-clinical population, the cannabis-related increase in selected positive and disorganised SPQ subscale scores was shown to be, at least in part, mediated by disturbance in salience processing mechanisms.

Topics: Cannabis; Humans; Psychometrics; Psychotic Disorders; Schizotypal Personality Disorder; Surveys and Questionnaires

There is a well-established relationship between cannabis use and psychosis, although the exact nature of this relationship is not fully understood. Recent studies have observed significant genetic overlap between a diagnosis of schizophrenia and lifetime cannabis use. Expanding on this work, the current study aimed to examine whether genetic overlap also occurs for subclinical psychosis (schizotypy) and cannabis use, as well as examining the phenotypic association between the traits. Phenotypic correlations were calculated for a variety of schizotypy and cannabis phenotypes in the UK Biobank (UKB), and single nucleotide polymorphism (SNP)-based heritability estimates and genetic correlations were calculated for these UKB phenotypes as well as for several other variables taken from recent genomewide association studies. Positive phenotypic correlations were observed between 11 out of 12 pairs of the cannabis use and schizotypy phenotypes (correlation range .05-.18), indicating a robust association between increased symptoms of schizotypy and cannabis use. SNP-based heritability estimates for two schizotypy phenotypes remained significant after multiple testing correction: social anhedonia (h2SNP = .08, SE = .02, N = 4025) and ever seen an unreal vision (h2SNP = .35, SE = .10, N = 150,717). Finally, one significant genetic correlation was observed between schizotypy and cannabis use, a negative correlation between social anhedonia and number of times used cannabis (rg = -.30, p = .012). The current study suggests the relationship between cannabis use and psychosis is also seen in subclinical symptoms of psychosis, but further research with larger samples is needed to determine the biological mechanisms underlying this association.

Topics: Cannabis; Humans; Marijuana Use; Phenotype; Polymorphism, Single Nucleotide; Psychotic Disorders; Schizotypal Personality Disorder

The ZNF804A gene and cannabis use are risk factors for psychosis and both have also been associated with schizotypal traits. This study aimed to investigate: i) the association of lifetime cannabis use (and its dose effect) with schizotypal personality traits, and ii) whether the genetic variability at ZNF804A gene modulates that association. Our sample consisted of 385 Spanish non-clinical subjects (43.1% males, mean age = 21.11(2.19)). Schizotypy was evaluated using the three factors of the Schizotypal Personality Questionnaire-Brief (SPQ-B): Cognitive-Perceptual (SPQ-CP), Interpersonal (SPQ-I) and Disorganized (SPQ-D). Subjects were classified according to their frequency of cannabis consumption, and dichotomized as users or non-users. The effects of a genetic variant of ZNF804A (rs1344706) and cannabis use, as well as their interaction, on each of the three SPQ-B factors were assessed using linear models and permutation tests. Sex, SCL anxiety scores and use of other drugs were included as covariates. Our analysis showed a significant relationship between ZNF804A and SPQ-I: AA genotype was associated with higher scores (β = 0.885 p

Topics: Cannabis; Female; Gene-Environment Interaction; Genetic Association Studies; Genetic Predisposition to Disease; Humans; Kruppel-Like Transcription Factors; Male; Marijuana Use; Polymorphism, Single Nucleotide; Psychiatric Status Rating Scales; Psychotic Disorders; Schizotypal Personality Disorder; Young Adult

The current study examined the relationship between early onset cannabis use (before age 16) and different schizotypy dimensions, and whether gender moderates these associations. Participants were 162 cannabis users, aged 15-24 years, who completed an online assessment examining alcohol and other drug use, psychological distress, and schizotypy. Participants were divided according to whether or not they had started using cannabis before the age of 16 (early onset=47; later onset=115) and gender (males=66; females=96). The interaction between gender and onset group was significantly associated with the dimension of introvertive anhedonia. Follow-up analyses showed that early onset cannabis use was associated with higher levels of introvertive anhedonia in females only. The current findings suggest that gender is an important moderator in the association between early onset cannabis use, schizotypy, and possibly, psychosis risk.

Topics: Adolescent; Cannabis; Female; Humans; Male; Marijuana Smoking; Psychotic Disorders; Schizotypal Personality Disorder; Sex Factors; Young Adult

Cannabis use has been related to an elevated psychosis risk and attenuated cognitive functioning. Cannabis-related cognitive impairments are also observed in populations along the psychosis dimension. We here investigated whether a potential behavioral marker of the psychosis dimension (attenuated functional hemispheric asymmetry) is even further attenuated in individuals using cannabis (CU) vs those not using cannabis (nCU). We tested 29 patients with first-episode psychosis (FEP; 11 CU) and 90 healthy controls (38 CU) on lateralized lexical decisions assessing left-hemisphere language dominance. In patients, psychotic symptoms were assessed by Positive & Negative Symptom Scale (PANSS). In controls, self-reported schizotypy was assessed (The Oxford-Liverpool Inventory of Feelings and Experiences: O-LIFE). Results indicated that nCU FEP patients had a relative reduced hemispheric asymmetry, as did controls with increasing cognitive disorganization (CogDis) scores, in particular when belonging to the group of nCU controls. Positive, disorganized and negative PANSS scores in patients and negative and positive schizotypy in controls were unrelated to hemispheric asymmetry. These findings suggest that cannabis use potentially balances rather than exacerbates uncommon hemispheric laterality patterns. Moreover, in healthy populations, the potential stabilization of typical hemispheric asymmetry in CU might be most relevant to individuals with elevated CogDis. We discuss the potential beneficial and harmful effects of cannabis use along the psychosis dimension together with propositions for future studies that should account for the mediating role of additional substances (eg nicotine), cannabis composition (eg cannabidiol content), and individual differences (eg physical health, or absence of significant polysubstance use).

Topics: Adult; Cannabis; Female; Functional Laterality; Humans; Language; Male; Psychotic Disorders; Schizotypal Personality Disorder; Young Adult

Previous studies analysing personality and cannabis use in adult samples suggest that cannabis users show significant higher levels of impulsivity, sensation seeking and schizotypy. However, there are few studies exploring this relationship in adolescence using psychobiological models of personality. Given the relevance of identifying individual differences that lead adolescents to early cannabis use to prevent future health problems, the present study aimed to explore the relationship between age, sex, personality and early cannabis use using a psychobiological model of personality in a sample of 415 students (51.8% boys) from 12 to 18 years. Chi(2) tests showed significant higher prevalence of cannabis use in boys and in the group aged 15-18 years. Multiple analysis of variance showed significant higher scores in psychoticism, sensation seeking and in all its subscales in cannabis users group, while an interaction with age was found for extraversion and neuroticism: cannabis users scored higher than non-users in the youngest group (12-14 years) but lower in the oldest group in both dimensions. Finally, regression analysis showed that narrower traits of sensation seeking (experience seeking and disinhibition) were the most associated to early cannabis use. Results are discussed in terms of early cannabis users' personality profiles and in terms of the self-medication theory.

Topics: Adolescent; Adolescent Behavior; Age Distribution; Anxiety Disorders; Cannabis; Female; Humans; Impulsive Behavior; Male; Marijuana Smoking; Neuroticism; Personality; Schizotypal Personality Disorder; Sex Distribution; Spain; Students; Surveys and Questionnaires

Both cannabis use and the dopamine receptor (DRD2) gene have been associated with schizophrenia, psychosis-like experiences, and cognition. However, there are no published data investigating whether genetically determined variation in DRD2 dopaminergic signaling might play a role in individual susceptibility to cannabis-associated psychosis. We genotyped (1) a case-control study of 272 patients with their first episode of psychosis and 234 controls, and also from (2) a sample of 252 healthy subjects, for functional variation in DRD2, rs1076560. Data on history of cannabis use were collected on all the studied subjects by administering the Cannabis Experience Questionnaire. In the healthy subjects' sample, we also collected data on schizotypy and cognitive performance using the Schizotypal Personality Questionnaire and the N-back working memory task. In the case-control study, we found a significant interaction between the rs1076560 DRD2 genotype and cannabis use in influencing the likelihood of a psychotic disorder. Among cannabis users, carriers of the DRD2, rs1076560, T allele showed a 3-fold increased probability to suffer a psychotic disorder compared with GG carriers (OR = 3.07; 95% confidence interval [CI]: 1.22-7.63). Among daily users, T carrying subjects showed a 5-fold increase in the odds of psychosis compared to GG carriers (OR = 4.82; 95% CI: 1.39-16.71). Among the healthy subjects, T carrying cannabis users had increased schizotypy compared with T carrying cannabis-naïve subjects, GG cannabis users, and GG cannabis-naïve subjects (all P ≤ .025). T carrying cannabis users had reduced working memory accuracy compared with the other groups (all P ≤ .008). Thus, variation of the DRD2, rs1076560, genotype may modulate the psychosis-inducing effect of cannabis use.

Topics: Adolescent; Adult; Cannabis; Case-Control Studies; Disease Susceptibility; Female; Gene-Environment Interaction; Humans; Male; Memory, Short-Term; Middle Aged; Psychoses, Substance-Induced; Receptors, Dopamine D2; Risk; Schizophrenia; Schizotypal Personality Disorder; Young Adult

While most neurochemical research into the pathogenesis of schizophrenia (SZ) has focused on the dopaminergic, glutamatergic, and serotonergic systems, the exact nature and cause of this disorder have proven intractable. Given the recent discovery and elucidation of the endogenous cannabinioid system, a re-examination of the cannabis-induced exacerbation hypothesis of SZ is warranted. The purpose of the present study was to assess whether current cannabis users exhibit personality correlates and neurocognitive deficits similar to those observed in SZ patients. 15 current cannabis users, 15 drug-free controls, and 10 past cannabis users were assessed on tasks which assess attentional inhibition, spatial working memory, olfactory identification, and schizotypal personality. Current cannabis users demonstrated deficits in attentional inhibition, decreased reaction time, and significantly higher scores on the schizotypal personality questionnaire (SPQ) compared with the non-using and past cannabis using groups. No group differences were found on the working memory or olfactory identification tasks. These results suggest that cannabis use can mimic attentional deficits seen in acute schizophrenia and is associated with schizotypal personality, thus setting the stage for a possible cannabinoid model of SZ.

Topics: Adult; Analysis of Variance; Attention; Cannabis; Case-Control Studies; Female; Humans; Inhibition, Psychological; Male; Memory, Short-Term; Schizotypal Personality Disorder; Smell

Topics: Adrenal Insufficiency; Adult; Anger; Anxiety; Cannabis; Chlorpromazine; Compulsive Behavior; Defense Mechanisms; Depersonalization; Dissociative Disorders; Humans; Male; Middle Aged; Pituitary Neoplasms; Psychoanalytic Theory; Schizotypal Personality Disorder; Substance-Related Disorders; Trifluoperazine

Topics: Adult; Cannabis; Cognition Disorders; Ethanol; Germany, West; Humans; International Cooperation; Legislation, Drug; Lysergic Acid Diethylamide; Male; Mental Disorders; Military Medicine; Military Personnel; Psychoses, Substance-Induced; Schizophrenia; Schizotypal Personality Disorder; Substance-Related Disorders; United States