Does Reclining Suppress Our Body's Sense of Fullness?

So. I've noticed a funny thing. First, some back ground. One of my favorite things to do is read in bed. Bed is one of the warmest places in the house (especially with an electric blanket) and of course, it's super comfy. I generally sit in a semi-seated, semi-reclined position, but I'm fairly well propped up so my arms don't get too tired from holding my book for hours on end.

Now, here's the funny thing: whenever I lay/sit in this position I feel hungry. Not stomach-growling kind of hungry, just not-full. And I think to myself, "Hmmm, I might be a little peckish. Maybe I better get up and get a snack." However, as soon as I get up my hunger disappears. Sometimes I think, "Oh well, I'll just have a snack anyway" and other times I think, "Well, guess I'm not hungry. I"ll just go lay back down." Regardless of which route I choose - snacking or not snacking - as soon as I lay back down in my semi-reclined position my stomach thinks it's empty again.

And one more thing: when I lay all the way down to go to sleep I can sense fullness again. So, standing, sitting all the way upright, or laying down I can sense fullness. But if I am semi-reclined I always feel somewhat empty.

This is too weird! Why is this happening? And it makes me wonder, "Do Lazy Boy recliners (and the like) cause people to overeat by somehow suppressing our ability to feel full?" I have no science to back this up. I'm just noticing this phenomena in my own body. Anyone else?