Self-hypnosis and exam stress: comparing immune and relaxation-related imagery for influences on immunity, health and mood

The effects of self-hypnosis training on immune function, mood and health at exam time in medical schools were examined, comparing instructions of enhanced immune function with relaxation, whereas instructions of increased energy, alterness, concentration and happiness were common to both procedures. Training consisted of three weekly group sessions, with unrestricted home practice with an audiocassette. Immune assays involved CD3, CD4, CD8, CD19 lymphocytes, CD56 natural killer (NK) cells and blood cortisol. Students receiving immune-related imagery reported fewer viral illnesses, such as colds and influenza, during the exam period. Immune-related imagery was also more successful than relaxation imagery in buffering decline in total lymphocytes and subsets. Independent of instructions, hypnosis buffered the decline in CD8 cytotoxic T-cells observed in control subjects, an effect associated with hypnotic susceptibility (Harvard group scale). Evidence of a buffering effect on NK cells could not be replicated, which may have been confounded by generalized stressors. As found previously, dissociations between negative mood and raised cortisol followed hypnosis training. These findings along with a contemporaneous one with patients with herpes—preliminary due to the small scale of the study—demonstrate for the first time that there are benefits for reported illness as a result of a psychological intervention shown to strengthen the immune system and improve well-being. The benefits of self-hypnosis encourage investment in large-scale illness prevention studies and controlled clinical applications