Continuous theta burst transcranial magnetic stimulation affects brain functional connectivity.

Area of Science:

• Neuroscience
• Cognitive Science
• Brain Imaging

Background:

• The prefrontal cortex (PFC) is crucial for emotional processing and brain network function.
• Right dorsolateral prefrontal cortex (DLPFC) hyperactivity is observed in anxiety, but its role in resting functional networks is unclear.
• Continuous theta burst transcranial magnetic stimulation (cTBS) can create temporary 'lesions' in specific brain regions.

Purpose of the Study:

• To investigate the impact of cTBS on the right prefrontal area on resting-state functional brain networks.
• To analyze changes in functional connectivity and network efficiency using graph theory metrics.
• To assess the effects across different frequency bands (delta, theta, alpha, beta).

Main Methods:

• Applied 40-second cTBS over the right prefrontal cortex in 13 healthy participants.
• Recorded 64-channel EEG data during resting-state conditions before and after cTBS.
• Calculated EEG channel coherence to construct functional networks and analyzed graph theory metrics (clustering coefficient, path length, efficiency-cost).

Main Results:

• Functional connectivity significantly increased across delta, theta, alpha, and beta bands after cTBS in the resting state.
• Maximum information transmission efficiency was observed at a cost of approximately 0.3, indicating high efficiency.
• Clustering coefficient and path length significantly increased in delta, theta, and beta bands post-cTBS.

Conclusions:

• cTBS applied to the PFC effectively enhances functional connectivity in the resting brain.
• Resting brain networks exhibit highly efficient information transmission at a specific cost threshold (around 0.3).
• The findings provide insights into the role of PFC in maintaining resting-state brain network organization and function.