Here is the most recent study on blast wave injury to the brain: https://www.ncbi.nlm.nih.gov/books/NBK299229/
This is why we got involved originally in 2004 when the Marines kept insisting their warriors didn’t need helmet pads, just the nylon strap suspensions. We testified to the House Armed Services Subcommittee on Air and and Forces about the difference in TBI rate between Army and Marines and the high number of Marines either killed or suffering significant TBI. After an all-day session, Congress ordered the MARINES to put pads in their fool helmets! Now to get them to put the RIGHT pads in! Too hard pads actually undo some of the protection offered by pads, as the blast wave instantly hardens pads a significant amount and can transmit more damage to the brain.