Publications by authors named "E Shokri-Kojori"
Oxytocin Reduces Methylphenidate-Induced Dorsal Striatal Dopamine Release in Male Rhesus Macaques.
Int J Neuropsychopharmacol
December 2024
Article Synopsis
- Oxytocin is being studied as a potential treatment for psychostimulant use disorders, particularly its effects on dopamine signaling in the striatum, a brain region linked to natural rewards.
- In a study involving male rhesus macaques, oxytocin was administered both intranasally and intravenously before administering methylphenidate, a stimulant similar to cocaine, and the impacts on dopamine release were monitored.
- Results showed that oxytocin significantly decreased dopamine release in the dorsal striatum when stimulated by methylphenidate, suggesting oxytocin may be useful in treating addictions to psychostimulants.
Background: Daylength and the rates of changes in daylength have been associated with seasonal fluctuations in psychiatric symptoms and in cognition and mood in healthy adults. However, variations in human brain glucose metabolism in concordance with seasonal changes remain under explored.
Methods: In this cross-sectional study, we examined seasonal effects on brain glucose metabolism, which we measured using 18F-fluorodeoxyglucose-PET in 97 healthy participants.
Examining the role of dopamine in methylphenidate's effects on resting brain function.
Proc Natl Acad Sci U S A
December 2023
Article Synopsis
- The study investigates how the amplitude of low-frequency fluctuations (ALFF) and global functional connectivity density (gFCD) are affected by variations in dopamine levels after administering methylphenidate (MP).
- The research used simultaneous PET-fMRI scanning on participants receiving either a placebo, intravenous (IV), or oral methylphenidate, revealing that IV-MP significantly altered brain activity metrics compared to oral administration.
- Results showed that gFCD relates to both the increase in dopamine levels and the rate at which it rises, while ALFF is only sensitive to the overall level of dopamine, indicating that these measures reflect different aspects of brain activation in response to stimulants.
The faster a drug enters the brain, the greater its addictive potential, yet the brain circuits underlying the rate dependency to drug reward remain unresolved. With simultaneous PET-fMRI we linked dynamics of dopamine signaling, brain activity/connectivity, and self-reported 'high' in 20 adults receiving methylphenidate orally (results in slow delivery) and intravenously (results in fast delivery) (trial NCT03326245). We estimated speed of striatal dopamine increases to oral and IV methylphenidate and then tested where brain activity was associated with slow and fast dopamine dynamics (primary endpoint).
View Article and Find Full Text PDFSubstance use disorder (SUD) is a chronic relapsing disorder with long-lasting changes in brain intrinsic networks. While most research to date has focused on static functional connectivity, less is known about the effect of chronic drug use on dynamics of brain networks. Here we investigated brain state dynamics in individuals with opioid use (OUD) and alcohol use disorder (AUD) and assessed how concomitant nicotine use, which is frequent among individuals with OUD and AUD, affects brain dynamics.
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