Search

Background: Dysfunction in brain network dynamics has been found to correlate with many psychiatric disorders. However, there is limited research regarding resting electroencephalogram (EEG) brain network and its association with cognitive process for patients with methamphetamine use disorder (MUD). This study aimed at using EEG microstate analysis to determine whether brain network dynamics in patients with MUD differ from those of healthy controls (HC). Methods: A total of 55 MUD patients and 27 matched healthy controls were included for analysis. The resting brain activity was recorded by 64-channel electroencephalography. EEG microstate parameters and intracerebral current sources of each EEG microstate were compared between the two groups. Generalized linear regression model was used to explore the correlation between significant microstates with drug history and cognitive functions. Results: MUD patients showed lower mean durations of the microstate classes A and B, and a higher global explained variance of the microstate class C. Besides, MUD patients presented with different current density power in microstates A, B, and C relative to the HC. The generalized linear model showed that MA use frequency is negatively correlated with the MMD of class A. Further, the generalized linear model showed that MA use frequency, scores of Two-back task, and the error rate of MA word are correlated with the MMD and GEV of class B, respectively. Conclusions: Intracranial current source densities of resting EEG microstates are disrupted in MUD patients, hence causing temporal changes in microstate topographies, which are correlated with attention bias and history of drug use. [ABSTRACT FROM AUTHOR]

Background and aims Chronic methamphetamine (MA) use is associated with cognitive impairment and psychopathological symptoms. This longitudinal study aims to examine the cognitive function of MA addicts during periods of abstinence. Methods Fifty-four MA dependent individuals and 58 healthy controls (HC) completed the psychological wellbeing scales and the CogState Battery that evaluated seven cognitive domains. During approximately 6-month abstinence, the subjects completed the CogState battery twice at the interval of 3 months. Results In the tasks of verbal memory, social emotional cognition, and spatial working memory, working memory, and problem solving the MA group performed worse than the HC group (P < 0.05). After 6-month abstinence, impaired verbal memory, social emotion, and problem solving were improved in the MA group (P < 0.01). Furthermore, the MA group showed lower scores in batteries of social adaptation ( t = 3.13, P = 0.002) and quality of life ( t = 3.70, P < 0.001) than the HC group, and 83.3% MA addicts displayed various psychiatric symptoms before study entry. Conclusions Chronic MA addicts exhibited impairment of some CogState battery domains and poor psychological wellbeing, and that some of these subdomains were recoverable on abstinence. Therefore, improved cognitive function should be considered an important component in the treatment of MA dependence. [ABSTRACT FROM AUTHOR]

Methamphetamine is one of the most commonly used drugs around the world, leading to serious public health and psychiatric problems. Due to the lackness of objective laboratory evaluation indicators, the molecular mechanisms of methamphetamine dependence still remain unclear. Previous evidence demonstrated that repetitive transcranial magnetic stimulation (rTMS) may be useful in treating drug addiction. The aim of this study was to identify and validate plasma metabolomics biomarkers in patients with methamphetamine use disorder before and after rTMS intervention. An untargeted gas chromatography–time-of-flight mass spectrometry (GC-TOFMS) based metabolomics approach was applied to characterize the metabolic profile of forty methamphetamine dependent subjects and thirty-eight healthy controls in peripheral blood mononuclear cells (PBMCs). Patients were randomized to receive either rTMS or sham over the DLPFC for four weeks (20 daily sessions, 900 pulses per day). Cognitive function were assessed before and after rTMS intervention. Eight PBMC metabolites responsible for distinguishing real rTMS from sham treatment were identified. These metabolites were mainly involved in energy metabolism and oxidative stress. Compared with baseline, the expression of three metabolites was reversed after rTMS intervention: alpha-tocopherol, glyceric acid and fumaric acid. Changes of the alpha-tocopherol were associated with cognitive function improvement following rTMS. These findings suggest that energy metabolism and oxidative stress system may be associated with the effect of rTMS on cognitive function in methamphetamine dependence, and warrant further investigation. [ABSTRACT FROM AUTHOR]

Craving and cognitive deficits are potential treatment targets for methamphetamine use disorder (MUD). Previous studies implied that transcranial direct current stimulation (tDCS) and cognitive training respectively improve these symptoms, but the combined effect is unknown. In this study, we investigated the combined effects of tDCS over dorsolateral prefrontal cortex (DLPFC) and computerized cognitive addiction therapy (CCAT) on cue-induced craving and cognitive functions among female individuals with MUD. Seventy-five patients with MUD were randomly assigned to three groups: CCAT + tDCS group, CCAT + sham tDCS group and the control group. The former two groups received 20 sessions of cognitive training combined 1.5 mA active/sham tDCS over DLPFC (20min/session, 5times/week), while the control group received usual care which includes routine medical care, health education, physical exercises and psychological support related to relapse prevention. The cue-induced craving and cognitive functions were tested at the baseline, the end of 2nd week and 4th week. The CCAT + tDCS group showed a significant reduction in cue-induced craving after 4-week intervention. Moreover, the craving score of the real CCAT + tDCS group was significantly lower than that of the CCAT + sham tDCS group and that of the control group at the end of 4th week. A significant improvement in accuracy of TWOB task was only observed in the CCAT + tDCS group at the end of 4th week when compared to baseline. Unexpectedly, participants who received CCAT plus active or sham tDCS did not change their discounting, whereas those in the control group performed more impulsively over time. The study found that the intervention of tDCS over DLPFC combined with CCAT may have potential benefit in improving treatment outcome in patients with MUD. More research is needed to explore the underlying mechanism. [ABSTRACT FROM AUTHOR]

Background: Repetitive transcranial magnetic stimulation (rTMS) is a brain stimulation and modulation electrophysiological technique, it can change cortical excitability of target brain region, modulate neuron plasticity and brain connections. Previous researches indicated that rTMS could reduce cue-induced craving in drug addiction.Objective: In this study, we employed real and sham rTMS of the left dorsolateral prefrontal cortex (DLPFC) to test whether it could reduce cue-induced craving for methamphetamine (MA) and influence cognitive function in a randomised clinical trial.Methods: Thirty MA-addicted patients were randomized to receive 5 sessions of 8min sham or 10Hz rTMS to the left DLPFC. Subjects rated their craving at baseline, after exposed to MA-associated cues and after rTMS sessions.Results: Real rTMS over the left DLPFC reduced craving significantly after 5 sessions of rTMS as compared to sham stimulation. Furthermore, real rTMS improved verbal learning and memory and social cognition in MA-addicted patients.Conclusions: The present study suggests that 10Hz rTMS of the left DLPFC may reduce craving and have no negative effects on cognitive function in MA-addicted patients, supporting the safety of rTMS in treating MA addiction. [ABSTRACT FROM AUTHOR]

Growing evidence suggests abnormalities in brain morphology including hippocampal structure in patients with methamphetamine (MA) dependence. This study was performed to examine hippocampal volume in abstinent MA users, and to further explore its relationship with cognitive function. 30 abstinent MA users (20 males and 10 females) with average 5.52 months of duration of abstinence and 29 healthy controls (19 males and 10 females) age 18–45 years old were recruited for clinical assessment and imaging scan. FreeSurfer was used to segment the hippocampus bilaterally, and hippocampal volumes were extracted for group and gender comparisons. Cognitive function was measured using the CogState Battery Chinese language version (CSB-C). Analysis of covariance (ANCOVA) controlling for education showed a significant group by gender interaction for the right hippocampal relative volume adjusted for total brain size ( p = 0.020); there was a significant difference between male controls and female controls ( p < 0.001), but such a difference did not exist between male patients and female patients ( p = 0.203). No significant correlations were found between hippocampal volume and cognitive measures. There seems to be a gender difference in how MA affects hippocampal volume in abstinent MA users. Hippocampus might be an important treatment target for cognitive improvement and functional recovery in this patient population, especially in females. [ABSTRACT FROM AUTHOR]