You are asking a question about which I have very little experience. I do see in Task Manager, when right clicking on the Chrome.exe entry, you may be able to change its priority to keep it from intruding. I have not seen a way to do this with the mouse, but I will have to do some research.
Other than that, if you check the Resource Monitor or Performance Monitor, do you see any system resources that are being heavily used? What percentage of your Memory or Disk is still available. If your hard drive was almost full, it could be involved. For instance, right now on my system, I am showing 20% of my Physical Memory used. If you were to show a much higher percentage, it might be involved. But basically, look around and keep you eyes open just in case you might notice something related to your mouse situation.
If it is a USB mouse, do you have any other USB devices plugged in?
If it involves Chrome, it might be related to the your network and resources being used to do something there. Maybe there is some toolbar, or some type of utility when Chrome is open that is receiving or sending information or checking some site.