AIMS: In this study, we investigated the effects of mitragynine on dopamine (DA) level and dopamine transporter (DAT) expression from the rat's frontal cortex.
METHODS: DA level was recorded in the brain samples of animals treated with acute or repeated exposure for 4 consecutive days with either vehicle or mitragynine (1 and 30 mg/kg) using electrochemical sensor. Animals were then decapitated and the brain regions were removed, snap-frozen in liquid nitrogen and immediately stored at -80 °C. DA level was quantified using Enzyme linked immunosorbent assay (ELISA) kits and DAT gene expression was determined using quantitative real time polymerase chain reaction (RT-qPCR).
RESULTS/OUTCOME: Mitragynine (1 and 30 mg/kg) did not increase DA release following acute treatment, however, after repeated exposure at day 4, mitragynine significantly and dose dependently increased DA release in the frontal cortex. In this study, we also observed a significant increase in DAT mRNA expression at day 4 in group treated with mitragynine (30 mg/kg).
CONCLUSION/INTERPRETATION: Data from this study indicates that mitragynine significantly increased DA release when administered repeatedly, increased in DAT mRNA expression with the highest tested dose (30 mg/kg). Therefore, the rewarding effects observed after mitragynine administration could be due to its ability to increase DA content in certain areas of the brain especially the frontal cortex.
METHODS: Initially, to develop constructs related to social media activities, web-based structured interviews were conducted with five office employees working in the oil and gas industry for the last 5 years. Then, using an online questionnaire survey, data was collected from 424 office employees working in the oil and gas industry in Malaysia. Using statistical software for social science (SPSS) and Smart PLS, exploratory factor analysis and confirmatory factor analysis were conducted to identify reliability and validity (discriminant validity, convergent validity and composite validity) of the constructs. Following this, path analysis was conducted and the moderating effects were identified.
RESULTS: Social media activities related to work-life decrease health and wellbeing by 11% and weaken the negative effect of effort-reward-imbalance on health and wellbeing by 17.6% at a 1% level of significance. The results of social media activities related to personal and social life strengthen the negative effect of effort-reward imbalance on health and wellbeing by 12% and negatively affects health and wellbeing and job rewards by 13, 55%, respectively. The direct effect of effort-reward imbalance and job efforts is significantly negative on health and wellbeing by 59 and 10%, respectively.
CONCLUSION: It is concluded that social media activities of the office employees significantly moderate the effect of effort-reward imbalance on health and wellbeing and intervene in job rewards in the organizations. Hence, the effect of social media activities reduces the health and wellbeing of office employees.
Aims: The primary objective was to evaluate whether addiction-specific cues compared with neutral cues, i.e., negative emotional valence cues vs. positive emotional valence cues, would elicit activation of the dopaminergic reward network (i.e., precuneus, nucleus accumbens, and amygdala) and consecutive deactivation of the executive control network [i.e., medial prefrontal cortex (mPFC) and dorsolateral prefrontal cortex (dlPFC)], in the PIGU subjects.
Method: An fMRI cue-induced reactivity study was performed using negative emotional valence, positive emotional valence, and truly neutral cues, using Instagram themes. Thirty subjects were divided into PIGU and healthy control (HC) groups, based on a set of diagnostic criteria using behavioral tests, including the Modified Instagram Addiction Test (IGAT), to assess the severity of PIGU. In-scanner recordings of the subjects' responses to the images and regional activity of the neural addiction pathways were recorded.
Results: Negative emotional valence > positive emotional valence cues elicited increased activations in the precuneus in the PIGU group. A negative and moderate correlation was observed between PSC at the right mPFC with the IGAT scores of the PIGU subjects when corrected for multiple comparisons [r = -0.777, (p < 0.004, two-tailed)].
Conclusion: Addiction-specific Instagram-themed cues identify the neurobiological underpinnings of Instagram addiction. Activations of the dopaminergic reward system and deactivation of the executive control network indicate converging neuropathological pathways between Instagram addiction and other types of addictions.