STUDY GUIDE 2026
____ (or commotion of the brain) was not causally tied to physiologic changes in the brain until
1839 - ANS ✔✔concussion
According to the CDC, mTBI represents ___/4 of all TBIs that occur in the US, which translates to
approximately 1.1 ____ persons incurring TBI each year - ANS ✔✔3, million
16-25% of those with a mTBI do not seek needed ___ care - ANS ✔✔medical
mTBI is characterized by any of the following: any period of loss of consciousness, any loss of
memory for events immediately before or after the incident, any alteration in ____ ____ at the
time of the incident, mild focal neurologic deficits, normal brain structure on CT/MRI (abnormal
would indicate moderate or severe) - ANS ✔✔mental state
LOC of 0-30 minutes indicates ____ TBI - ANS ✔✔mild
LOC of 30 min-24 hours indicates ____ TBI - ANS ✔✔moderate
LOC of >24 hours indicates ___ TBI - ANS ✔✔severe
Alteration of consciousness from a moment up to 24 hours indicates ____ TBI - ANS ✔✔mild
Alteration of consciousness >24 hour severity indicates ____ TBI (in conjunction with other
criteria) - ANS ✔✔moderate
Post-traumatic amnesia from 0-1 day indicates ____ TBI - ANS ✔✔mild
, Post-traumatic amnesia from 1-7 days indicates ____ TBI - ANS ✔✔moderate
Post-traumatic amnesia >7 days indicates ____ TBI - ANS ✔✔severe
Glasgow Coma Scale of 13-15 indicates ___ TBI - ANS ✔✔mild
Glasgow Coma Scale of 9-12 indicates ____ TBI - ANS ✔✔moderate
Glasgow Coma Scale of 3-8 indicates _____ TBI - ANS ✔✔severe
In mTBI, the transfer of kinetic energy can lead to adverse chemical changes (____ ____), or
direct damage to physical structures such as brain cells. - ANS ✔✔metabolic alterations
____ ____ ____ is the most common form of damage to a brain structure - ANS ✔✔diffuse
axonal injury
In diffuse axonal injury, axons are twisted and disconnected, a process called ____ ____ - ANS
✔✔axonal shearing
Diffuse axonal shearing cannot be readily seen using typical imaging methods (CT, MRI), so it is
diagnosed solely by use of ____ definitions - ANS ✔✔behavioral
The most important metabolic alteration is the massive release of neurotransmitter called
_____ - ANS ✔✔glutamate
Athletes under the age of ____ are at the greatest risk for second-impact syndrome if they
return to play while still neurologically at risk - ANS ✔✔24