Psychoneuroimmunology
http://onlinelibrary.wiley.com/doi/10.1046/j.1365-2036.2002.01359.x/abstract

Brain neural pathways, the brain-gut-immune axis and IBS.
http://www.ncbi.nlm.nih.gov/pubmed/10784583

Brain-Gut-Immune axis as a bi-directional axis:
http://gut.bmj.com/content/60/3/307.abstract

Hypnotherapy specific to IBS, gut directed hypnotherapy
http://www.ncbi.nlm.nih.gov/pubmed/6150275
http://www.ncbi.nlm.nih.gov/pubmed/2563797
http://www.ncbi.nlm.nih.gov/pubmed/22310221,
http://www.ncbi.nlm.nih.gov/pubmed/22296841