New PET study offers insight into how dopamine drives executive function
Using PET imaging, researchers have gained valuable insight into how dopamine production impacts executive function.
Cognitive flexibility is critical to the ability to adapt behavior to changing environments. It is driven by dopamine production, with higher levels providing greater flexibility and those who have lower levels often struggling with adaptability during certain tasks.
This latest research allowed researchers to study the release of dopamine in the brain using radiotracers to track it during two sets of tasks. The team, who published their findings in the Journal of Nuclear Medicine, is hopeful their findings could guide the development of new treatments for psychiatric and neurological disorders.
“At the neurotransmitter level, the dopamine system has been linked to cognitive flexibility. A direct neurochemical response to cognitive flexibility, however, has yet to be shown,” Isabelle Miederer, PhD, associate professor in the department of nuclear medicine at University Medical Center Mainz in Germany, and colleagues noted. “In our study, we sought to examine the release of dopamine in real time by performing PET scans while individuals completed behavioral flexibility tasks.”
For the study, participants underwent PET scans using the D2/3 receptor ligand 18F-fallypride while they completed two sets of tasks—one that did not require them to switch between rules and another involving rule-switching. Researchers calculated dopamine release during both tasks using the linearized simplified reference region model.
On imaging, alterations in the presence of 18F-fallypride were observed in the ventromedial prefrontal cortex. These were most notable during the task that required alternating between sets of rules that are considered more cognitively challenging.
The changes related to 18F-fallypride displacement are believed to signal the release of dopamine. Additional findings revealed that participants with higher dopamine release also performed better during the rule-switching task, further confirming the role of dopamine in individuals’ ability to adapt.
“The present findings emphasize the significance of dopamine in cognitive flexibility,” the authors noted. “They are consistent with the results of previous clinical studies indicating that dopamine deficiency in disorders such as Parkinson’s disease may cause behavioral deficits in cognitive flexibility.”
Learn more about the findings here.