to answer your question:
yes. when the body is cold, it tires to protect vital organs by reducing the blood flow to them. when its warm, the blood flows throughout the entire body better and its able to mvoe more oxygen through the brain, resulting in a more powerful sleep with more vivid dreams.

i have the opposite reaction to you though. i live on the second (third if you be american) floor directyl under the roof. my flat is faced southwest, so i have it pretty warm. i have it too warm, cant sleep so i need less bedding. i have a very hard time sleeping ebcause my brain never rests, its always rattling. and the warmer it is, hte harder it is for me to sleep...