I haven't examined physiological barriers to psychological change yet, and I don't intend to, in depth, until I either know what I'm talking about or can convincingly fake it. But the continual trouble I've had waking up at 5:30AM has me wondering.
I can go to bed early, arrange to wake up to a relaxing, unstressful massage, turn on the lights immediately, and cement a routine all I want, but after a year and a half of having to wake up at 5:30 for work, it's still almost impossible. My body has not adjusted. Which I find odd, having lived halfway around the world which, if my body were really unable to adjust to a different rhythm, would've had me going to sleep at what felt like 8AM and waking up at what felt like 5PM. For six months. With no sign of it feeling natural. But it did feel natural there, after only a few days. I had to exert no effort to adjust. Here, with my 5:30AM alarm, I can exert all the effort in the world but it doesn't catch for some reason.
The book I'm reading has a section about how our systems are the most depressed (relaxed, not sad) between the hours of 4 and 6 AM and there's nothing much we can do about it. However, it doesn't make clear whether it's because of the local light-dark cycle or it's something that becomes ingrained in our bodies from the time zone we're born in. From my experience and a good dose of common sense, I'm guessing it's the former.
Here's another example. Right up until I went to Indonesia, I had pretty bad skin. Medicated scrubs did not help, eating less greasy food did not help, washing my face all the time did not help. Again, despite all efforts to change and erect a new habit, the habit, while duly erected, did not produce anything in the form of any physiological evidence of change. The only thing that ended the ten year Reign of Acne was changing climates. Only once I was enmeshed in 85+ degree air holding 85+ per cent humidity, and my pores started pouring constantly, rivering everything bad out 24/7, did my skin clear up, and, amazingly, has stayed basically that way since.
Both of these examples are painfully obvious, so painfully obvious that I feel stupid including them in a blog entry The reason for the psychological change failing is that it's powerless against the larger forces of biology.
It's slightly discouraging to think that, for all the problems we face, any one of them might have some kind of hidden monstrosity of a biological blockade that prevents us from getting anywhere with it, even if we try our hardest.