What are concussions, how do they occur, and what are the short and long-term complications and concerns associated with them?

In the recent years, concussions in children and young adults during sporting events has been getting more and more attention due to the complications of them. What are concussions, how do they occur, and what are the short and long-term complications and concerns associated with them?

Chronic traumatic encephalopathy (CTE) is a major long-term concern associated with repeated brain trauma, such as concussions. Does the research on CTE provide enough evidence for more action to be taken regarding concussions that occur during junior high, high school and college sporting events? For example, should an athlete suffer two or more concussions, should he/she be restricted or banned from playing that sport? After this research- do you or would you have concerns about your child/ren playing a sport where concussions could commonly happen, such as football, hockey, or soccer?