Publications by authors named "Helga Welzel"
Background: Chronic cannabis use has been associated with memory deficits and a volume reduction of the hippocampus, but none of the studies accounted for different effects of tetrahydrocannabinol (THC) and cannabidiol (CBD).
Methods: Using a voxel based morphometry approach optimized for small subcortical structures (DARTEL) gray matter (GM) concentration and volume of the hippocampus were measured in 11 chronic recreational cannabis users and 13 healthy controls, and correlated with THC and CBD from hair analyses. GM volume was calculated by modulating VBM using Jacobian determinants derived from the spatial normalization.
Aims: In the present study, the effect of previous detoxifications on prefrontal function and decision making was examined in alcohol-dependent patients. Further, we examined whether the length of abstinence affects cognitive function.
Methods: Forty-eight alcohol-dependent patients were recruited from an inpatient detoxification treatment facility and cognitive function was compared to a control group of 36 healthy controls.
Background: It is unclear whether impairment in decision making, measured by the Iowa Gambling Task (IGT), in addiction is substance-induced or the consequence of personality structure.
Methods: Analysis of the IGT, the Tridimensional Personality Questionnaire (TPQ) and cannabinoids in hair and urine were performed in 13 cannabis users and matched controls.
Results: Hair Delta(9)-tetrahydrocannabinol (THC) correlated negatively with the last subtrial (cards 80-100) of the IGT (R = -0.
Background: Cannabinoids present neurotoxic and neuroprotective properties in in vitro studies, inconsistent alterations in human neuroimaging studies, neuropsychological deficits, and an increased risk for psychotic episodes.
Methods: Proton magnetic resonance spectroscopy ((1)H-MRS), neuropsychological testing, and hair analysis for cannabinoids was performed in 13 male nontreatment-seeking recreational cannabis users and 13 male control subjects.
Results: A significantly diminished N-acetylaspartate/total creatine (NAA/tCr) ratio in the dorsolateral prefrontal cortex (DLPFC) was observed in cannabis users (p = .
The aim of this work was to evaluate the relationship between the amount of alcohol consumption of a group of social drinkers and the magnetic resonance spectroscopy signal of choline-containing compounds (Cho) in the frontal lobe. Two independent long echo (TE = 135 ms) (1)H MRSI studies, the first comprising 24 subjects with very low alcohol consumption, the second 18 subjects with a more widespread alcohol consumption were conducted. Significant correlations of Cho measures from frontal white matter and from the anterior cingulate gyrus with alcohol consumption in the last 90 days prior to the MR examination were found.
View Article and Find Full Text PDFOpioid withdrawal, stress or cues associated with opioid consumption can induce opioid craving. If opioids are not available, opioid-dependent patients usually search for alternative drugs. Because several non-opioid drugs stimulate the endogenous opioidergic system, this concept may explain their frequent use by opioid-dependent patients.
View Article and Find Full Text PDFBackground: This study focused on metabolic brain alterations in recently detoxified alcohol-dependent patients (S1) and their possible reversibility after 3 (S2) and 6 months (S3) of abstinence.
Methods: Thirty-three alcohol-dependent patients and 30 healthy control subjects were studied with multislice proton magnetic resonance spectroscopic imaging (echo time = 135 msec at 1.5 T at three time points).