Increased Heschl's Gyrus Duplication in Schizophrenia Spectrum Disorders: A Cross-Sectional MRI Study

Predictive impact of different acute cannabis intoxication effects with regard to abstinence motivation and cessation of use

Cannabis use is a common risk factor for psychoses. But although prevalence of consumption as well as potency of cannabis increased, the incidence of schizophrenia remained stable. The discontinuation hypothesis suggests that a potential increase of psychoses incidence may be relativized by more frequent cessation of consumption due to higher rates of adverse psychosis-like intoxication effects (PLE), caused by stronger cannabis. A mixed methods online survey was administered to 441 current and past users to analyze the predictive impact of different acute intoxication effects regarding abstinence motivation/cessation of use. Our hypothesis was that PLE would be experienced as the most aversive intoxication effect and therefore have the highest predictive significance. Possible confounds were included (craving, patterns of consumption and sociodemographics). Further analyzes compared past versus current users regarding the quality of intoxication effects, suggesting that past users retrospectively experienced more unpleasant experiences than current users. Free-text data explored subjective reasons for abstinence. We found that paranoid/dysphoric intoxication effects were most predictive for abstinence motivation. Less predictive were psychosis-like intoxication effects such as hallucinations. Group comparisons revealed significant more unpleasurable and less positive intoxication effects in past users compared with current users. Current users with the intention to stop consumption showed significantly more paranoia/dysphoria intoxication compared to users with no intention to stop use. As a conclusion, different intoxication experiences have different effects on abstinence motivation and substance use behavior. They therefore provide a focus that should be increasingly integrated into treatment concepts.

Development and initial validation of a reliable German self-report measure to assess acute cannabis intoxication-effects (CanTox-17)

OBJECTIVES

Both positive and negative including psychotic-like cannabis intoxication effects are well-established. Yet, consequences for consumption patterns, addictive behavior or psychotic developments are poorly researched in general, in Germany not at all. Thus, objective was to develop the first German-language questionnaire operationalizing acute cannabis intoxication effects, based on the original "Cannabis Experience Questionnaire" (CEQ).

METHODS

After expert translation of the CEQ, items related to acute intoxication effects were presented to a sample of 537 cannabis users. Four- and five-factorial solutions of explorative factor analysis with a randomly split sub-sample 1 were cross-validated by confirmatory factor analysis on sub-sample 2.

RESULTS

After content review of factors and analysis of external validity, a 17 item four-factorial model was approved. Factors are (1) "paranoia/dysphoria", (2) "confusion/disorientation", (3) "euphoria/creativity", (4) "psychosis-like/loss of reality". Model fit is satisfactory (RMSEA = 0.058, SRMR = 0.065, CFI = 0.929, TLI = 0.914). Correlations with corresponding external measures support construct validity.

CONCLUSIONS

The present questionnaire is a time-efficient, valid and reliable instrument. Thus, predictors of different cannabis intoxication effects can be analysed for the first time in German-speaking area, as well as their significance for substance use or psychosis risk.

Different Frequency of Heschl’s Gyrus Duplication Patterns in Neuropsychiatric Disorders: An MRI Study in Bipolar and Major Depressive Disorders

An increased prevalence of duplicated Heschl’s gyrus (HG) has been repeatedly demonstrated in various stages of schizophrenia as a potential neurodevelopmental marker, but it remains unknown whether other neuropsychiatric disorders also exhibit this macroscopic brain feature. The present magnetic resonance imaging study aimed to examine the disease specificity of the established finding of altered HG patterns in schizophrenia by examining independent cohorts of bipolar disorder (BD) and major depressive disorder (MDD). Twenty-six BD patients had a significantly higher prevalence of HG duplication bilaterally compared to 24 age- and sex-matched controls, while their clinical characteristics (e.g., onset age, number of episodes, and medication) did not relate to HG patterns. No significant difference was found for the HG patterns between 56 MDD patients and 33 age- and sex-matched controls, but the patients with a single HG were characterized by more severe depressive/anxiety symptoms compared to those with a duplicated HG. Thus, in keeping with previous findings, the present study suggests that neurodevelopmental pathology associated with gyral formation of the HG during the late gestation period partly overlaps between schizophrenia and BD, but that HG patterns may make a somewhat distinct contribution to the phenomenology of MDD.

Different Heschl's Gyrus Duplication Patterns in Deficit and Non-deficit Subtypes of Schizophrenia

Deficit syndrome schizophrenia is a characteristic subtype defined by persistent negative symptoms and poor functional outcomes; however, the biological mechanisms underlying this specific subtype have not yet been elucidated in detail. The present magnetic resonance imaging study examined the prevalence of duplicated Heschl's gyrus (HG), a potential neurodevelopmental marker, in schizophrenia patients with (N = 38) and without (N = 37) the deficit syndrome. The prevalence of the HG duplication pattern bilaterally was higher in the whole schizophrenia group than in 59 matched healthy controls. Furthermore, the prevalence of right HG duplication was significantly higher in the deficit schizophrenia group than in the non-deficit schizophrenia group. The HG pattern in schizophrenia was not associated with clinical variables, including illness duration, medication, and symptom severity, while right HG duplication correlated with higher scores for Proxy for the Deficit Syndrome. The present results suggest that the prominent neurodevelopmental pathology associated with gyral formation of HG may contribute to enduring negative symptomatology in schizophrenia.

Heschl's gyrus duplication pattern and clinical characteristics in borderline personality disorder: A preliminary study

Inter-individual variations in the sulco-gyral pattern of Heschl's gyrus (HG) might contribute to emotional processing. However, it remains largely unknown whether borderline personality disorder (BPD) patients exhibit an altered HG gyrification pattern, compared with healthy individuals, and whether such a brain morphological feature, if present, might contribute to their clinical characteristics. The present study used magnetic resonance imaging to investigate the distribution of HG gyrification patterns (single or duplicated) and their relationship to clinical characteristics in teenage BPD patients with minimal treatment exposure. No significant difference was noted for the prevalence of HG patterns between 20 BPD and 20 healthy participants. However, the BPD participants with left duplicated HG were characterized by higher prevalence of comorbid disruptive behavior disorders, with higher externalizing score compared with those with left single HG. Our preliminary results suggest that neurodevelopmental pathology associated with gyral formation might be implicated in the neurobiology of early BPD, especially for emotional and behavioral control.