Doctors believe the 22-year-old former U.S. army specialist is suffering from traumatic brain injury following an explosion.

He lost part of his leg and now uses a prosthetic one. 

His brain is still in the process of healing. 

“My memory has not been anywhere near what it used to be. Retaining information is difficult. When I try to speak, I draw a blank on words,” said Cook.

He complained of anxiety and crippling headaches. 

Military doctors said it was Post Traumatic Stress Disorder [PTSD]. 

Cook knew something different was wrong - something physical that doctors did not seem to catch. 

“They didn’t give me all of my options. I don’t’ think they wanted to try because they thought they’d figured it out. They decided it was PTSD because their one scan didn’t show TBI [traumatic brain injury]." 

Dr. Stephen Xenakis - a psychiatrist and retired army brigadier general now in private practice - carefully examined Will’s case in a way he said military doctors sometimes do not have the time to do. 

“You’ve got the culture of the military that is - rightly so - so focused on the mission that they’ve got as many people into combat, on the playing field, as they can,” said Xenakis.

The case of Staff Sergeant Bales has drawn attention to this military hospital on his home base in the state of Washington. The facility is under investigation after hundreds of service members had their PTSD diagnoses reversed - decisions that critics say were motivated by concerns over the high cost of treating mental health issues. 

The army says the problem is not systematic. 

Xenakis said money can be a factor in military doctors’ treatment decisions - as can other issues such as experience, time spent with the patient, and sheer luck. 

“Does that mean there needs to be more sensitivity, that perhaps it’s best to err on the side of over-diagnosing? That’s a question that needs to be considered here,” said Xenakis.

For Cook, more than 30 hyperbaric oxygen treatments have made a difference. 

“I haven’t had any headaches anymore. The ringing in my ears has stopped. My memory started getting better. I’m retaining information better. Recall of words is better. My anxiety has gone down a lot to a more manageable level." 

Cook has no plans to return to the military, but he is going on with his life. Just a few months ago, he could not remember simple things like phone numbers. 

Now, he is getting ready to start college.