Post-concussion syndrome
About 10% of people with PCS develop sensitivity to light or noise, about 5% experience a decreased sense of taste or smell, and about 14% report blurred vision. People may also have double vision or ringing in the ears, also called tinnitus. PCS may cause insomnia, fatigue, or other problems with sleep.
Pittsburgh Penguins Foundation
The test, which all NHL players undergo, evaluates the athlete's neurocognitive state which includes brain processing speed, memory, and visual motor skills. If the player suffers a concussion, these test results are then used in order to compare their previous neurocognitive state to that of their possible concussed state. Baseline testing is used because concussions do not show up on CT or MRI scans due to it not being a structural brain injury. Testing is necessary because symptoms vary from person to person. These symptoms range from nausea, dizziness, concentration problems and/or fuzzy vision. The testing is done by the UPMC Sports Concussion group on the computer program ImPACT.