I don't have this particular book and I don't understand what he means by a hysterical disorder.
What is the difference between psychosomatic, hysterical, tms etc.?? I don't know and when I read about it, it doesn't become clear either. Like many other "disorders" that have a psychological interaction, there are many theories and explanations about what is really happening. The DSM is in many places nothing more than the momentary (or economically driven) opinion of the majority of "experts" (in my opinion

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I see it as unnecessarily complicating things, so therefore I think you are 100% correct by saying that they are all physical problems that originate from the mind. I would rather say psychophysiological symptoms that originate from the mind, because many symptoms are a mixture of both.
The globus hystericus, which I think is a poorly chosen name because it suggests that you have to be hysterical to suffer from it, is driven by emotions and is often seen with people who suffer from anxiety or depression. I know the feeling personally from when I suffered from mild depression many years ago. When you keep focusing on it, you can become so anxious that you might even enter a state of panic. Maybe this is why he uses the word hysterical, because to an outsider it looks like you greatly overreact to something benign ????
I read something that the muscle in play mainly is the one that keeps your throat closed so you won't drown when submerged in water. So it has its function in survival-states (fight, flight).
the mechanism: initial onset (something that initiates a survival reaction; brewing emotions like in the TMS theory or a real threat that is consciously or unconsciously perceived) -> lump in the throat from tightened muscles (survival reaction) -> hyper-vigilance (hyperfocus on the survival reaction) -> fear or even panic (about the initial survival reaction) ......you have now entered the vicious circle ........-> lump in the throat stays around or gets worse -> hyper-vigilance continues -> fear or panic continues -> .....etc. etc..
and if you follow Sarno, you are now fully occupied by the symptoms instead of possible emotions that are brewing in the background.
treat it like any other psychophysiological symptom: don't worry about it, just accept the lump to be there, because it is benign and it is generated by emotions. Once your mind learns that you won't fight or fear the feeling, it doesn't see it as a threat anymore (or it acknowledges that it has lost its function to distract you from brewing emotions) and the physical reaction will subside (or changes to another location in your body).
easily said, doing it is something that can be rather difficult... but always keep in mind that, unless a doctor tells you otherwise, the lump-feeling is caused by a benign reaction to some sort of threat.
eager to learn what other have to say about this, hope it helps you.