Does the use of parchment change the baking time or temperature?

Parchment was suggested to me here in reference to baking cookies. I tried it for the first time today, on a batch of cinnamon sugar cookies, which called for greasing the cookie sheets. I used parchment instead, without greasing or spraying.

The cookies came out doughy inside—first time that’s ever happened to me. I calibrated the new oven on the basis of my experience with oatmeal cookies a couple of weeks ago and increased the baking time accordingly, but still they were not done in the middle. (Cookies that start out brown are harder to judge for doneness on the basis of color.) Twenty seconds in the microwave took care of that, but the question remains. There are confounding variables here—use of parchment, new stove—and I would like to know if I can eliminate one. Does parchment create extra insulation or cause any other change that affects the results?

Thank you.