Does neurofeedback work with the ADD population?
The American Academy of Pediatrics has endorsed Neurofeedback as a treatment equivalent to medication for the treatment of ADD and ADHD.
Does neurofeedback work for other disorders like anxiety and depression?
The Association for Applied Psychophysiology and Biofeedback (AAPB) used the research criteria developed by the American Psychological Association (APA) for treatment efficacy to biofeedback and neurofeedback treatments for a number of disorders. This reference "Evidence Based Practice in Biofeedback and Neurofeedback" is available at the link below:
What evidence is there that LENS works?
One study, specifically about LENS, is particularly important because its large sample size (N=100) lends credibility to its utility:
Larsen, S., Harrington, K., Hicks, S. The LENS (Low Energy Neurofeedback System): A Clinical Outcomes Study on One Hundred Patients at Stone Mountain Center, New York. Journal of Neurotherapy, Vol 10, No. 2/3, 2006 pp. 69-78.
One hundred patients (selected randomly from over 300 cases) ranging in ages 6 to 80 had at least 10 LENS sessions each. Average symptom ratings across 15 major problem areas (e.g., anxiety, mood disturbance, attention problems, fatigue, pain, sleep problems, etc.) showed significant improvement (p<.0001) from beginning to end of treatment. Statistically significant reduction in EEG amplitudes were evident as well.
The following books explain the use of LENS across an number of diagnostic categories: