Biofeedback can be used for many purposes, which range from improving an athlete's concentration by how he focuses, such as a golf player improving their swing, to reducing stress symptoms caused by a person with high blood pressure.
Since I am a person with an anxiety disorder, as defined by The Diagnostic and Statistical Manual of Mental Disorders (4th Ed; DSM-IV), I tried biofeedback to deal with my anxiety. Biofeedback sessions are often run in 10 to 20 sessions, and higher sessions are recommended for more severe cases. Because of my hope in this therapy, I exceeded 20 sessions, and tried around 40 (or more).
I think biofeedback can alleviate some anxiety, but it cannot cure anyone with severe anxiety. For me, I define this as someone that has experienced panic attacks, especially around their development years, and has experienced prolonged anxiety attacks in adulthood, which can lead to clinical depression. If you fit this description, and I'm guessing you do, since you are going to a website that attracts people with anxiety issues that exceed the norm, be weary of biofeedback.
My regret is that after 20 sessions, I was under the placebo that this therapy would cure me, if I just kept on hitting those biofeedback machines. This procedure is often advertised as being more natural, as part of the category of alternative medicine, because it works with the body's brain and doesn't involve the use of psychiatric drugs, I was under the spell that it was a better alternative.
For those who try to pursue alternative therapies, outside of the prescribed treatments of cognitive behavior therapy and medication (which are approved by most insurances, and alternative therapies are usually not), if you start accumulating a lot of sessions, you should reevaluate your treatment methods.
If you keep on thinking biofeedback is the better route, after a tally of sessions, then you are under the placebo effect that this therapy is helping you. A real therapy would not take so much time to fix your anxiety symptoms.
Your therapist will probably not complain if you continue more sessions, since you are a guaranteed source of income. Although a biofeedback therapist, or any alternative therapy practitioner will be your friend in therapy, outside therapy, they are no longer a friend. This may sound cynical, but I've done a lot of therapy to validate this, but you really are a form of business in how they make money, and taking time to talk to you involves money, and without your money, you would not be advised.
This is not to say therapists are not effective, and money can get your more competent therapists, so you technically get what you pay for. But your therapist will not be objective on what is the appropriate healing modality for you, and push biofeedback as a fix for your anxiety, however, learning from my experience, biofeedback is not a healing modality for most anxiety disorders.
Even after a year of biofeedback, in conjunction with other body therapies, my anxiety disorder still got triggered, and I had to experience panic disorder all over again.
So, what I've learned is that quantity of sessions with biofeedback does not guarantee permanent relief from an anxiety disorder.
There are segments of the population who benefit from biofeedback, such as people who want to improve their concentration in athletic skills, and people who have slight anxiety issues with high blood pressure, but for those who suffer anxiety disorders, this therapy is a waste of money.
You may enjoy a couple of games of Pac Man as you brain is monitored by the biofeedback machines, but when biofeedback session can cost $60 to $90 dollar a session, that's an expensive game habit.