I would say most people don't actually "think" they're hungry rather than perceive they're hungry. The hunger response is not a higher-level cognitive function;

I would say most people don't actually "think" they're hungry rather than perceive they're hungry. The hunger response is not a higher-level cognitive function; it is regulated by the lower brain. When it reaches the level at which you can reason about (and picture a hamburger), it is more than likely that you already are aware of your hunger.