A nerve injured with its cell body cannot regenerate and is considered killed. The loss of neurons is usually compensated by the following three mechanisms.
• Replacing the lost neurons if the cell body is functioning
• Adapting to do more with less
• Learning new ways to solve problems
Thus, the blanks can be filled with, (1). Replacing the lost neurons if the cell body is functioning, (2). Adapting to do more with less, (3). Learning new ways to solve problems.