We find that there is a big misunderstanding by people about the difference between the signs of a brain injury or post concussion and the symptoms that occur.
Remember that the signs are those things that people around the victim will notice about them. They can be confused, have glassy eyes, they might be sleeping excessively or they may not be responding or finding the right words. Maybe their personality has changed or they have motor issues, their ability to move, walk or what have you. There's a whole list of various signs that may be visible to those around you after a brain injury but they're might not be any at all.
At the other end of the spectrum, you have the symptoms. The symptoms are what the victim is feeling, the person who has suffered a concussion or brain injury. These are things that inwardly you know are going on. You may not be able to work as fast mentally, you might not be able to find words, your personality has changed, or maybe you can't find directions that you knew before. You could be more aggressive or more lethargic. Again, there is a whole list of ways that symptoms may occur after a brain injury.
It's important to understand these various things. We've got a great discussion of this in our brain injury handbook, which we make available on our website for free. I urge you, particularly if you're having these symptoms to get the information that you need so that you can make those around you aware and get the proper diagnosis for what's going on.
You can download The Layman's Guide to Brain Injuries here.