Our Providers


Robert F. Calhoun, Ph.D.

Dr. Calhoun is a clinical psychologist who specializes in neuropsychology, chronic pain, psychological trauma, and general behavioral medicine. Dr. Calhoun trained at Washington State University and University of Washington Medical School and Health Sciences Center. Dr. Calhoun is the director of the Brain Injury Program at St. Alphonsus Regional Medical Center where he practices clinical neuropsychology and rehabilitation psychology. In his private practice he evaluates and treats patients with acute stress or post traumatic stress disorder, including first responders; patients with neurological disorders, chronic pain, and psychophysiological disorders. Dr. Calhoun also provides evaluation and treatment of injured workers and consults with a work hardening program. He has a love of teaching and continues his teaching and supervision of psychology and medical students. Dr. Calhoun has studied and practiced Jeet Kune Do for the past 25 years and incorporates many of Bruce Lee's philosophical principles in his clinical work. Dr. Calhoun is also a board member of Idaho 2 Fly, which is an organization that takes men with cancer on fly fishing retreats. Dr. Calhoun would like to thank his loving wife of 30 years Stacy, daughter Chandler, and his two sons John and Joshua for their unending love and unconditional support.


Michael D. Johnston, Ph.D.


Dr. Johnston began his private practice at MSCPS in 1997. He specializes in both Clinical Psychology and Forensic Psychology. He conducts individual psychotherapy with adults seeking advice about mood management, relationship skills, and life purpose. With regards to forensic work, he performs Risk Assessments for judges, attorneys, probation officers, parole officers, and treatment providers. The Risk Assessments include Psychosexual Evaluations, Domestic Violence Evaluations, and estimating risk for general criminal behavior. He has held numerous leadership positions, most recently being the Chairman of the Sexual Offender Management Board for the State of Idaho. In his private life he enjoys watching movies with his adult autistic son, spending time with his wife, socializing with friends and family, golfing, hiking, and exercising.


Brett W. Thomas, Ph.D.

Dr. Thomas has had the pleasure of providing pediatric services for MSCPS since 2004, including psychological/neuropsychological evaluations, learning/developmental evaluations, and family/individual therapy. He completed his Ph.D. at Idaho State University and had the amazing opportunity to spend a year completing his predoctoral internship at Father Flanagan's Boys Town in Omaha, Nebraska. When he is not working, Dr. Thomas enjoys travelling and spending time with his wife, two teenage children, and three dogs.


Jason D. Gage, Ph.D.


Dr. Gage completed his Ph.D. in Psychology at Utah State University. He then served as an Officer and Psychologist in the U.S. Army during internship and at Fort Lee, Virginia as the Chief of Mental Health Services. Following military service at Fort Lee and Mountain Home Air Force Base, Dr. Gage began working as a neuropsychologist at St. Alphonsus Rehabilitation Services (STARS) and in private practice at Mountain States Counseling and Psychological Services. Dr. Gage currently specializes in general neuropsychology, to include brain injuries, dementia, sports concussion management (credentialed ImPACT consultant), and ADHD/Learning Disorders in children and adults. Dr. Gage also conducts adult evaluations for individuals suspecting a possible Autism Spectrum Disorder (ASD). Dr. Gage has a specific interest in aviation psychology and provides neuropsychological evaluations for pilots/prospective pilots needing an evaluation for the FAA. The FAA has designated Dr. Gage as a qualified provider for these services, to include HIMS (alcohol related) evaluations. With his military background, Dr. Gage has specialized in treating posttraumatic stress disorder (PTSD) and other anxiety disorders.