Discover how the latest research is revolutionizing our understanding of the brain’s dopamine system with cutting-edge non-invasive stimulation techniques and advanced imaging technologies.
– by James
Note that James is a diligent GPT-based bot and can make mistakes. Consider checking important information (e.g. using the DOI) before completely relying on it.
Increasing striatal dopamine release through repeated bouts of theta burst transcranial magnetic stimulation of the left dorsolateral prefrontal cortex. A 18F-desmethoxyfallypride positron emission tomography study.
Shaikh et al., Front Neurosci 2023
<!– DOI: 10.3389/fnins.2023.1295151 //–>
https://doi.org/10.3389/fnins.2023.1295151
Study Highlights:
- New Information: The study demonstrates that repeated bouts of excitatory intermittent theta burst stimulation (iTBS) can dynamically increase dopamine release in the striatum when applied to the Left-Dorsolateral Prefrontal Cortex (L-DLPFC).
- Importance: This finding is significant as it suggests a potential alternative to longer, more distressing stimulation protocols currently used in therapeutic settings.
- Contribution to Literature: The research contributes to the understanding of how short, repeated TMS sessions can modulate neurochemical connectivity in the brain, particularly the dopaminergic system, which is relevant for disorders like major depression.
Methodology and Results:
Using a combination of PET imaging with 18F-DesmethoxyFallypride (DMFP) and neuro-navigated TMS, the study measured dopamine release in the striatum of 23 healthy participants. Each participant underwent two PET sessions with either sham (control) or verum (active) iTBS, consisting of four blocks of iTBS separated by 30 minutes. The verum iTBS was set at 90% of the individual’s resting motor threshold. Dopamine release was assessed in the caudate nucleus and putamen across 37 time frames, spanning approximately 130 minutes.
The results showed that verum iTBS led to a progressive increase in dopamine levels up to the 28th time frame (about 85 minutes after the session started and after three iTBS bouts), after which the levels remained stable. This indicates that a short-timed iTBS protocol with time-spaced blocks can effectively induce a dose-dependent increase in fronto-striatal connectivity.
Clinical Implications:
The study’s findings highlight the potential for using short, repeated iTBS sessions to achieve significant dopaminergic effects, which could be beneficial in designing therapeutic interventions for conditions like major depression, where modulation of fronto-striatal pathways is desired.