According to the most recent international consensus of concussion experts (1), concussion signs (those noticed by coaches, parents and teammates) and symptoms (feelings or problems experienced by the athlete) fall into five "clusters":
1. Symptoms
2. Physical signs (loss of consciousness (LOC) [2], amnesia [3])
3. Behavioral changes (irritability, sadness, nervousness, more emotional, depression)
4. Cognitive impairments (slowed reaction times etc.)
5. Sleep disturbance (insomnia, drowsiness, sleeping less than usual, sleeping more than usual).
1. McCrory P, et al. Consensus statement on concussion in sport: the 4th International Conference on Concussion in Sport held in Zurich, November 2012. Br. J. Sports Med 2013;47:250-258.
Links:
[1] https://www.momsteam.com/node/221
[2] https://www.momsteam.com/node/150
[3] https://www.momsteam.com/node/203
[4] https://www.momsteam.com/health-safety/concussion-signs-and-symptoms-physical-cognitive-emotional-sleep-related