Brown University researchers have found that healthy people who take ADHD drugs may experience consistent changes in positive emotion, according to an online university news release published March 12.  

Specifically, researchers found the drugs to increase glutamate, the most abundant neurotransmitter in the brain responsible for learning and memory, and also identified a causal link to the duration of positive emotional responses to the drug. Additionally, White and colleagues found that women showed a larger increase in glutamate compared to men.  

“This is the first time that an increase in brain glutamate in response to psychostimulant drugs has been demonstrated in humans,” said lead author Tara White, PhD, an assistant professor in the Brown University School of Public Health, in a prepared statement. “That’s important since glutamate is the major neurotransmitter responsible for excitation in the brain and affects learning and memory.” 

According to the news release, study participants were first screened for mental and physical health. They then underwent MRI spectroscopy scans to detect the concentration of neural compounds in specific the anterior cingulate cortex, which connects multiple brain networks involved in emotion, decision-making and behavior.  

“[The] present findings provide the first evidence in humans that drug-induced changes in [glutamate] correlate with subjective experiences of drug liking and drug high following drug ingestion,” researchers said according to the press release.   

Study findings were published online on March 6 in the journal Neuropsychopharmacology.