Trevor McCauley was just a little boy walking by a horse corral when his life changed.

The horse, 17 hands high, had already kicked over the top of some fencing when it landed a hoof against the 10-year-old's skull. He went down instantly with a grievous injury behind his left ear. His heart stopped, and his dad, Richard McCauley, had to use CPR until the air ambulance arrived and the crew revived him.

His mom, Julie McCauley of Layton, thought they had lost him. But they really only lost parts of him — the pieces that often fall away with traumatic brain injury. In his case, it's short-term memory and balance, common sense and impulse control.

The pieces are a little different for Troy Roper, 62, who in 2005 was riding his motorcycle — helmet on, he emphasizes — when a car made an illegal U-turn into him. His head crashed through the side window, his lungs collapsed, his heart was bruised and he spent 102 days in the hospital. His losses are different: His left vocal cord and right side have paralysis. His eyes are fine, but the signal to his brain is scrambled, resulting in cortical blindness. His intestine was badly damaged. And a tape recorder worn like a necklace now substitutes for the immediate memory that he lost.

Julie McCauley and Roper recount these stories because there's a statewide traumatic brain injury (TBI) conference Thursday and Friday at the Davis Conference Center in Layton. They both support the Brain Injury Association of Utah and hope families who deal with TBI will join the network to help and be helped.

Trevor was in a coma for six weeks, suffering four lateral skull fractures and two neck fractures. His family was told he might not walk again because his cerebellum was so damaged.

Through hard work, he's regained much of what he lost that day. His folks and sister Mandee worked with him every day at the pool for eight months, until he could walk. A year after the accident, he received a Presidential Award for academics. He's been in Junior Jazz and karate. But it's a roller-coaster ride, his mom says, the victories somehow sweeter because they're so hard won with the cognitive and physical deficits left by the horse's ill-placed hoof.

Because of the injury, his heart doesn't always regulate right. His internal thermostat gets out of whack. He has double vision and migraines and tinnitus and he's losing his hearing. Now in high school, he works harder than most of his peers just to break even because of short-term memory deficits. His intact long-term memory reminds him of what he lost, Julie McCauley says.

His biggest issue — and this is common — is safety, because brain injury often disrupts the impulse-control center. And because it's usually a hidden injury, people look at someone who has a brain injury without recognizing their challenges. The judgments can be pretty harsh, she said.