Kurt Othmer from EEGInfo created a video response to a report out of McGill University that was published in June in The Lancet Psychiatry (which is not open-source) that dismisses the effects of all EEG neurofeedback as due to the placebo effect. Kurt describes how it is not possible for the effects that we see in the clinic to be due to the placebo effect – he cites some original research on cats (when was the last time you saw a cat do what you wanted them to do?) to current research with addicts showing a significantly higher retention rate in treatment recovery programs when the treatment is combined with neurofeedback. He also discusses how we can modulate the effects of the neurofeedback during a session, using the specific example of modulating a headache – making it better and making it worse in the same session by changing the response frequency (the brainwave at which the brain is training).
This video is worth watching, especially if you have doubts about the effects of neurofeedback and are worried that it may not be worth your investment: