recording interference help

I am brand new to the Wi-spy world, having recently acquired a unit to perform wifi debugging at a nonprofit org I help out on occasion. In doing tests at home and at work, with 3 different computers, I have noticed a very distinct signal pattern emerging. There is a peak at 2413 mhz, and an array of smaller peaks at 2425, 2437, 2449, 2461, 2473, 2495.