Briefly lose connection every time I do search

I have a subscription to Avast Internet Security which I bought in 2014. A few days ago I noticed that my connection will briefly (a few seconds) drop and then re-connect no matter what browser I use. During the brief outage, I’ll get a message that I have no internet connection and then the connection will automatically resume. I have only one computer, a desk top wired, Windows 7, 64 bit system. This is very annoying. How can I stop it from happening? Thanks for your help.

Let me clarify this a bit…each time I go to a different screen, Avast does a scan. That little Avast icon spins when the scanning takes place. At that point, I briefly lose the connection and a red x will appear on the screen icon at the lower left of the computer screen. This is a new problem and all was fine until a few days ago. How can I stop this incessant scanning that is causing connectivity problems?