Veterans exposed to explosions who do not report symptoms of traumatic brain injury (TBI) may still have damage to the brain's white matter comparable to veterans with TBI, according to researchers. Veterans of recent military conflicts in Iraq and Afghanistan often have a history of exposure to explosive forces from bombs, grenades and other devices, although relatively little is known about whether this injures the brain. However, evidence is building – particularly among professional athletes – that subconcussive events have an effect on the brain.