LTagard,

The study was either flawed or just slanted. The brain training industry has been pulling out all the stop to sell their programs. The recent research shows that each exercise causes an increase in ability to do that exercise. The cross-over value is limited. The key value is at developing underdeveloped skills. Developing observational skills. Developing focus skills.

If you really wanted to maximize your brain, you should have been learning to play the piano and violin from a young age while the brain was more formative.

Deuce,

You are mistaken if you think a quick recovery means there was no damage. Your boxer friend exhibited signs of a concussion. There are plenty of athletes who never suffered a single concussion but developed severe Chronic Traumatic Encephalopathy, as early as their 20's, from hits with much less force than the average boxers punch.

Heading a soccer ball, especially during heading drills, is known to cause cumulative damage. No head aches or other symptoms but damage happens.

So, tell your friends to be careful. The brain is for thinking, not hitting.

The goal of boxing is to cause brain damage. Otherwise, head hits would be outlawed and body blows would be the rule.