Our Team

Chad Hickerson, Heritage Oaks Hospital’s Chief Executive Officer, began his career in behavioral health in 1996. He is an established health care professional with decades of experience in the fields of medical and behavioral health care leadership. He has held several key leadership positions in his career, both in the public sector (Hospital Administrator, Chief of Mental Health, Career Executive Assignment) and private sector (Chief Executive Officer, Regional Director of Operations, and Vice President of Operations), specializing in public/private partnerships. Chad holds a master’s degree in Organizational Development (focus in Leadership) and has bachelor’s degrees in Health Care Administration and Sociology. Chad is known for bringing patient-centered care, a focus on safety, and results to some of the most complex treatment settings, while developing and supporting the people they serve.

Dr. Sison has served as the medical director for Heritage Oaks Hospital since 2006 and is an associate clinical professor in the Department of Psychiatry and Behavioral Sciences at UC Davis School of Medicine. He graduated from UCLA School of Medicine and completed his general psychiatry residency training at St. Elizabeth’s Hospital in Washington, D.C.

Dr. Sison is also a child psychiatrist and finished his child psychiatry training at the University of Maryland Medical Systems. He is a longtime active community member in Sacramento and had previously served as medical director for Sacramento County Child and Family Mental Health for 11 years. He has served on various boards of directors in Sacramento, including the Big Brothers, Big Sisters of Sacramento and the Head Trauma Support Project. He is a previous president of the Central California Psychiatric Society, a district branch of the American Psychiatric Association.

Although Dr. Sison specializes in the treatment of mood disorders in children and adolescents as well as being an expert in treating children with ADHD, his psychopharmacology expertise also serves him well in the treatment of various adult psychiatric illnesses, such as bipolar disorder, depression and schizophrenia.

Melanie Nelson, COO has been working in behavioral health for 22 years. She graduated from the University of North Carolina at Chapel Hill with a master’s degree in social work with a concentration in Administration. She also has a bachelor’s degree in psychology and social work from North Carolina State University.

Melanie previously worked for Providence Health Services for 12-years as the Director of Providence Kodiak Island Community Mental Health Center in Kodiak, AK. During her time there, the Mental Health and Substance Abuse Centers were merged into a single facility and began a whole-person approach for patients struggling with a dual diagnosis.

In 2010, Melanie moved to Anchorage and began her career with UHS at North Star Behavioral Health, an inpatient behavioral health psychiatric facility. The facility served children, preteens, and adolescents across Alaska. She became the Administrator for the main campus in 2015.

In 2017, Melanie moved to Sacramento, CA to become the Chief Operating Officer at Heritage Oaks Hospital.

Cathawyne W. Paul, MSN, BSN, RN-BC, has served in nursing roles at Heritage Oaks Hospital since 2003. She accepted the position of Assistant Director of Nursing in 2007 and was promoted to the position of Director of Nursing Services, due to her extensive and administrative nursing experience.

Earlier in her career, Cathawyne was the Nurse Administrator of the Department of Mental Health and Substance Abuse for the government of Guam. In addition, she served in American Samoa as the Coordinator for the Alcohol/Drug Program in the Department of Public Health. As well as serving on the psychiatric nursing staff as a manager for the Alcohol and Drug Unit at the Washington Hospital Center, Washington, DC.

Cathawyne earned her Master of Science in Nursing Leadership and Administration from Western Governor’s University, Salt Lake City, UT. She received her Bachelor of Science in Nursing from Hampton University, Hampton, VA, with a national certification in Psychiatric Nursing. She is a member of the American Nursing Association, as well as the American Psychiatric Nursing Association.