Hi All:
This is from my email:
Q:
Thanks for all the information you have been giving out. To say that it has changed my life would be an understatement.
I have a question for you. I hope you can refer me to where in your book I can find answer to this.
In your lessons you have talked about blockages manifesting themselves in different physical forms. In some other lessons you have talked about seeing lights in your eyes during early steps towards enlightenment.
Where do you draw the line, and decide to see if this is actually a physical ailment, or is caused by yoga practices?
Here is my scenario - I started practices I learned in your lessons, seriously about a year ago. I have been increasing duration. I have also had a mild neck ache problem. For the past few months it has been severe. At first I wrote it off as energy blockages, and adjusted, but the problem did not go away. I finally went to a doctor, and with his help, discovered that the problem was due to an external cause. Addressing that has provided some relief.
I also started seeing some flashes in my eyes. This normally would be encouraging, but I saw a doctor. The doctor told me that this is a condition known as posterior vitreous detachment, and the flashes are a bad thing. He told me to not try to make the flashes appear. I did some internet research, and discovered that the symptoms match. Had I not consulted the doctor, I could have harmed my eyes tremendously.
I don’t want to run to the doctor every time I see something. However, I also do not want to attribute physical symptoms to yoga practices only. So, I am trying to figure out some simple ways to determine when it is appropriate to go to the doctor, and when to take it as an effect (good or bad) of yoga practices.
Thanks.
A:
The simplest way to avoid spiritual symptoms being confused with medical symptoms is to be diligent in applying self-pacing. This means not overdoing in practices, and making adjustments as necessary. Then we will always have reasonable control over results from practices, and if something is happening that is medical, we will have a much better chance of spotting it.
So, do not overdo with sambhavi, yoni mudra, chin pump or other practices that can strain the eyes or neck. The goal is not to see flashing lights. The goal is to gradually cultivate inner silence and ecstatic conductivity. Gradually. If we are doing that, we will not have extreme symptoms. Then if we do have symptoms, we will know better to go see a health care professional.
Of course, I am idealizing things a bit, because there will be times when spiritual symptoms will be strong even with light to moderate practices, so there will be times when the line between spiritual and medical symptoms will be blurred. In those times, we are best to go for safety first with self-pacing and medical advice as we deem necessary, as you have wisely done. The other side of this is the fact that practices like chin pump and sambhavi can aid in clearing up symptoms if these are related to spiritual energy blockages. So, there can be some trial and error in practices during these times. When there are symptoms that seem to be energy related, we can test lightly with practices, and if there is no relief, we back off. I am thinking of chin pump here, and numerous cases we have seen where blockages of energy in the neck have been relieved. But in your case, this apparently was not so, which points to the need for always keeping the medical aspect in mind, and always treading carefully with our practices.
Then again, it is also possible for medical professionals to diagnose spiritual symptoms as medical. It happens all the time in the psychology field with visions, kundalini experiences, etc. So, we always have to use our common sense before being led off into drug treatments and other things that may or may not be treating real illnesses.
As time goes on, the medical profession will gain better understandings of these matters, as will we as practitioners. The AYP forums are a good place to network on these things, so I am going to put this one in there (anonymously) for the group to consider. It is a fascinating subject – one that I am sure will receive increasing attention in both the medical and yoga communities as we see more and more individuals exhibiting the signs of human spiritual transformation. Society is going to have adapt to the reality of spiritual awakening rising everywhere. There is lots of evidence of it in the neurobiology, yes?
The good news is that we are forging ahead and plowing new ground in the field of applied yoga science. If nothing were happening, we would have much more to worry about. 
Btw, the business of flashing lights is also covered in lesson #194, assuming a spiritual symptom in that case. But the warning is always there to be prudent and not ignore symptoms that could be medical.
Wishing you the best on your chosen path. Enjoy!
The guru is in you.