So thats where the abiltiy to injoy things comes from? From are nervous system or brain?
You should have enjoyable events in life. You should be able to experience joy even if it's in the smallest things like seeing a sunrise, or holding a baby, etc.. If you can get no enjoyment out of anything in life, then that is not a good thing.
At times our lifes can become quite depressing when negative events overwhelm us and overtake all the good in our life. We may also become physically depressed where our nervous systems lose it's ability to experience pleasure, even without some event causing it.
If you feel you fit into either one of these categories then you should see your doctor and explain your feelings to him/her.
So you mean its not a good think living like this without any injoyment in life?
Loss of interest in things that were once enjoyable is one of the most common symptoms of depression. It in and of itself is not a conclusive diagnosis of depression so you should seek medical attention if this and other symptoms are interfering with the quality of your life.