Attic Insulation/Shadows on Ceiling

Hello - I'm new here - just looking for some opinions/advice. We have some odd grayish-colored shadows appearing in some of the ceiling area in our house - along the front side of the house and the back side (in other words the edges of the ceiling areas closest to the guttering on the front and back side of the house - but nothing in the middle of the ceilings at all). Our house is a regular ranch-style. A while back we had a professional come and inspect the insulation in the attic, directly above where these "shadows" are occurring on the ceiling. He said that it looked as though the insulation had somehow been moved or blown out of the way (it is "loose" insulation/blown-in), and he believed the lack of insulation coverage in those specific areas are what caused the shadows. We moved the insulation back into place, but the shadow spots still feel cold to the touch - we didn't think they would after the insulation was put back where it belongs. We are also concerned about the potential for mold growth - although we cannot find any signs of that - and these shadows have been there for several months now. Could these dark places be caused by the insulation being moved, or by something else, and what do we do about the fact that these places continue to feel cold to the touch even after the insulation has been moved back into place? I may also need to mention that we had a new roof put on in 2009 and there weren't any leaks prior to that, or after. Any and all responses are appreciated. And a picture is attached of one of the areas. Thanks!

While the insulation was push back, this would have been a cold zone on the ceiling. Moisture could have condenced there at that time. While the ceiling was damp at that time dust in the house would stick to it. In the attic there should be batt insulation over the walls to stop wind from moving the loose stuff around and there should be foam shoots that direct air up the roof.

I have seen this before in a house which was had 'patchy' insulation.
Although likely not a whole lot of moisture condensed in this area, but like Neal says just a little coldness would cause discoloration.

In the home I refer to above, it turned out to be particulate/soot/grime/petroleum build up enhanced by the cold areas on the exterior walls and in some places on the ceiling. We freshly painted the entire interior of the home upon move in, but after only a short time of 2-3 years we noticed this. We lived in a cold climate and had a oil furnace. Add to that fireplace usage 20 times a year, a kerosene heater 10-15 times a year and my wife's love for candles and we had particulate/petroleum condensation problems. You can confirm this if you also notice it on your windows if they seem to get dirty quickly.

Anyway, you will need to repaint that ceiling with a good primer then ceiling paint. Walls can usually be washed of this type of grime if the paint underneath is not flat base.