This randomized controlled trial investigated the effects of high-frequency repetitive transcranial magnetic stimulation (rTMS) on gastrointestinal injury and autonomic function in patients with acquired brain injury (ABI). Sixty-four ABI patients with acute gastrointestinal injury (AGI) were randomized into a control group (n=32) receiving standard rehabilitation and an rTMS group (n=32) receiving standard rehabilitation plus 10 Hz rTMS over the left ventrolateral prefrontal cortex (VLPFC-L). The rTMS intervention consisted of five sessions per week for two weeks. Autonomic function was assessed via heart rate variability (HRV), and whole-brain functional connectivity was measured using 106-channel functional near-infrared spectroscopy (fNIRS), with graph-theoretical network metrics analyzed. Compared to the control group, the rTMS group showed reduced acute gastrointestinal injury scores. HRV analysis revealed decreased low-frequency (LF) power, a lower low-frequency to high-frequency (LF/HF) ratio, and increased high-frequency (HF) power in the intervention group. Functional connectivity increased in the left ventrolateral prefrontal cortex (VLPFC-L), specifically with the right frontal pole, bilateral premotor cortices, and the left pre-motor/supplementary motor cortex. Global and local network efficiency also improved. The study concludes that VLPFC-L-targeted rTMS can restore neuroautonomic integration and gastrointestinal function in ABI patients and demonstrates the potential of fNIRS and HRV as complementary tools for assessing neuromodulation effects on autonomic circuits. The abstract does not report specific p-values, confidence intervals, or safety data.
After a stroke or serious brain injury, the body's internal control system can get damaged. This often leads to a dangerous condition called acute gastrointestinal injury, where the gut stops working properly. Doctors have been looking for ways to repair this broken connection between the brain and the gut. In this study, 64 patients with this gut injury were split into two groups. Both groups got standard rehabilitation. One group also received a special, non-invasive brain stimulation treatment called high-frequency rTMS, targeted at a specific area on the left side of the brain's frontal lobe, for two weeks. The results showed that the group receiving the brain stimulation had lower scores for their gut injury. Their heart rate variability—a key measure of how well the automatic nervous system is working—also improved, showing better balance. When researchers looked at brain activity, they found that the stimulation strengthened connections in the brain's control network, particularly around the stimulated area and to other regions involved in planning and movement. The overall efficiency of this brain network improved. This means that stimulating this specific brain area can help restore the brain's ability to regulate automatic bodily functions, offering a potential new therapy for a debilitating complication of brain injury.
What this means for you: Targeted brain stimulation can help restore gut function in patients recovering from a stroke or brain injury.
View Original Abstract ↓
Autonomic dysfunction resulting from damage to the central autonomic network is a common complication of acquired brain injury (ABI). The prefrontal and insular cortices regulate visceromotor autonomic functions, and gastrointestinal dysfunction following ABI may involve impaired autonomic innervation. While repetitive transcranial magnetic stimulation (rTMS) shows potential for studying the top-down control of visceral processes, the mechanisms linking disrupted functional connectivity to autonomic dysfunction and the restorative effects of neuromodulation remain unclear. Sixty-four ABI patients with acute gastrointestinal injury (AGI) were randomized into a control group (CG, n = 32) and an rTMS group (TG, n = 32). Both groups received standard rehabilitation, while the TG additionally underwent 10 Hz rTMS over the left ventrolateral prefrontal cortex (VLPFC-L) (five sessions per week for two weeks). Autonomic function was assessed via heart rate variability (HRV), and whole-brain functional connectivity was measured using 106-channel functional near-infrared spectroscopy (fNIRS). Graph-theoretical network metrics were analyzed. Compared to the CG, the TG showed reduced acute gastrointestinal injury scores, decreased low-frequency (LF) power, a lower low-frequency to high-frequency (LF/HF) ratio, and increased high-frequency (HF) power. Functional connectivity increased in the left ventrolateral prefrontal cortex (VLPFC-L), particularly with the right frontal pole, bilateral premotor cortices, and the left pre-motor/supplementary motor cortex. Global and local network efficiency also improved. These findings indicate that VLPFC-L-targeted rTMS can restore neuroautonomic integration and gastrointestinal function in ABI patients. This study demonstrates the potential of fNIRS and HRV as complementary tools for assessing the effects of neuromodulation on autonomic circuits.