A<unk>  is a traumatic brain injury (TBI) that may result in a bad headache, altered levels of alertness, or unconsciousness.
It temporarily interferes with the way your brain works, and it can affect memory, judgment, reflexes, speech, balance, coordination, and sleep patterns.
Concussion
Quenching 
Hypnic jerk
Lamaze
Stretching
Forehead lift
Valsalva maneuver
Percussion