• Posted September 26, 2024

Brain Injury & PTSD: Veterans' Study Suggests Area of Damage Is Key

Brain damage that veterans suffered from flying shrapnel has provided a major clue that could lead to better treatment for post-traumatic stress disorder (PTSD), a new study says.

Veterans who suffered shrapnel damage connected to their amygdala, the fear center of the brain, were less likely to develop PTSD, researchers reported Sept. 24 in the journal Nature Neuroscience.

The results suggest that PTSD could be treated by using electrical pulses to disrupt brain networks linked to the amygdala, they added.

“This is a very real brain disease, and we can localize it to certain brain circuits,” said corresponding author Dr. Shan Siddiqi, a psychiatrist in the Brigham and Women’s Hospital Center for Brain Circuit Therapeutics. “Unfortunately, people sometimes assume PTSD has to do with how mentally strong or weak a person is, but it has nothing to do with moral character.”

Researchers previously have uncovered brain networks to successfully treat depression and addiction using neurostimulation, and have been trying to locate the network associated with PTSD.

For this study, the research team examined 193 patients from the Vietnam Head Injury Study who’d suffered brain injuries from shrapnel penetrating their skulls.

“Some of these veterans who got shrapnel in their head went on to develop PTSD, but many of them did not,” said study co-author Dr. Michael Fox, director of the Center for Brain Circuit Therapeutics. “The patients actually developed PTSD less than other veterans who did not get damage to their brain.”

Researchers mapped where the shrapnel brain damage had occurred in the brains of these veterans, and compared the data to 180 veterans who didn’t have brain damage.

The comparison found less PTSD in veterans who had shrapnel-caused lesions in the brain network tied to the amygdala.

The team also reviewed data from previous clinical trials involving neurostimulation, to see if the circuit they’d highlighted had already been targeted in some patients.

“The trials where stimulation was hitting the circuit we identified tended to be the trials that had good outcomes in patients,” Fox said.

During the study, a patient in California with severe PTSD requested treatment with transcranial magnetic stimulation (TMS), in which a brain implant uses a magnetic field to generate electrical pulses in specific parts of the brain.

Doctors used TMS to target the brain circuit identified by the study of veterans, and the man’s PTSD improved, researchers report.

While it’s only one patient, the case shows how this brain circuit could be used to treat PTSD, Fox said.

However, there will need to be clinical trials in a larger group of patients before this therapy can be approved by the U.S. Food and Dug Administration, researchers said.

“While more work remains to be done, we’ve taken an important step here to identify a therapeutic target for a condition in patients who desperately need better treatments,” Fox said.

More information

The Cleveland Clinic has more on transcranial magnetic stimulation.

SOURCE: Brigham and Women’s Hospital, news release, Sept. 24, 2024