In my experience as a Reiki Therapist, I found it surprising for many people, when i was able to detect the hidden causes of their troubles/suffering, whether realized/unrealized by them.
For ex : When a patient was being treated for Intense Headache, during physical examination, disturbances were found in Solar Plexus. She was suffering constipation and that was the reason for headache.
Apart from these, during other treatments, many such other feelings of anxiety/fear/mood disturbances/emotional upsets/willingness or unwillingness for the session/ etc… were noticed.
The reason being, in Reiki Therapy, it is the Recipient’s body itself, which draws the energy and the Reiki healer , hence , becomes eventual to the actual disturbances. Moreover, if the Recipient is unwilling for the treatment, Reiki itself stops flowing, hence reciprocating the feeling.
Pasted below , is one another important link for Clear understanding of Reiki :
http://www.neurosurgical.com/neuro_medical_info/alternative_care/reiki_therapy.htm
Cures by Reiki 