Awhile ago I took up an interest in finally learning scales, and lead work. I'm doing alright, and have found my "comfort zone" with my wrist, but i'm now wondering about forearm positioning. Not so much arm positioning for the higher frets, but on the lower ones. I keep my wrist as straight as possible when playing scales, thumb on the back of the neck, pointed towards the headstock, and I try to line my palm up parallel to the neck so that everything is straight and even and fingering with the 3rd/4th fingers is easier and more even. I also keep my elbow close to my body as I play, as it feels more natural when playing on the higher frets, of course. So my question is this, when playing on the lower frets, should I keep my elbow close to my body, or should I let it move with my wrist, so that both are always aligned for more comfort and easier playing? I've just heard somewhere that keeping your elbow close to your body is a good thing, not sure how much truth there is to that...
Experienced opinions would be much appreciated!

Thanks alot!
regards,
- Adrian