About Us


Click on the staff member below that you would like to know more about.


Michael S. Trieger, Psy.D.

Michael TriegerDr. Michael Trieger is cofounder of the Springfield Psychological Center, a private practice established in 1992. Prior to entering private practice, Dr. Trieger served seven years as an Assistant Professor of Clinical Pediatrics in the Southern Illinois University School of Medicine’s Division of Developmental and Behavioral Pediatrics.

Dr. Trieger received his Master of Arts and Doctoral degrees from Yeshiva University and completed an internship in Pediatric Psychology at the University of Maryland School of Medicine. He also earned certification as a Mediation Counselor from the University of Wisconsin.

Dr. Trieger’s current areas of clinical interest include: evaluation of learning and attention disorders, the effects of chronic and/or catastrophic illness in children, and grief/ bereavement counseling. Individual and family psychotherapy are treatment modalities utilized by Dr. Trieger. He has also presented on a wide variety of lecture topics and in-service training workshops to parents, educators, and fellow professionals. Dr. Trieger performs consultative psychological examinations for the Illinois Bureau of Disability Determinations, the Department of Human Services, the Department of Children and Family Services, and the Veteran’s Administration.

Dr. Trieger credits his wife and his four children with teaching him the importance of humility and humor in psychotherapy.

Melissa Fisher Paoni, Ph.D.

Melissa Fisher PaoniMelissa Fisher Paoni, Ph.D., is partner/co-owner of the Springfield Psychological Center, and is a Licensed Clinical Psychologist and Certified School Psychologist (Board Certified by the National Association of School Psychologists). She earned her Doctoral degree from Illinois State University in 2000, and completed a pediatric psychology doctoral internship at the Southern Illinois University School of Medicine. She participated in multidisciplinary Children’s Miracle Network clinics and became a faculty member in the Pediatrics Department at SIU before entering private practice.

Dr. Paoni has taught several college psychology courses, authored articles, and made professional presentations to local, state, and national audiences on topics involving developmental and learning issues. She has been co-president and treasurer of the Central Illinois Psychological Society.

Dr. Paoni’s clinical interests include learning disabilities, ADHD, emotional and behavioral adjustment issues, and developmental disorders. She provides individual psychotherapy, behavioral consultation, and diagnostic evaluations of children and adolescents.

Dr. Paoni enjoys watching movies with her daughter, listening to her husband’s band, and getting as much summer sun as possible.

Helen Pugacz Appleton, Ph.D., ABPP

Helen Pugacz AppletonHelen Pugacz Appleton, Ph.D., has been a Licensed Clinical Psychologist since 1981. She received her undergraduate degree from Augustana College and her Master of Arts and Doctoral degrees from Loyola University of Chicago. Dr. Appleton is Board Certified in Forensic Psychology by the American Board of Professional Psychology.

Dr. Appleton’s primary areas of interest include sexual abuse; forensic issues; PTSD; and anxiety and depressive disorders in children and adults. She works with many families on divorce and visitation issues. She offers consultative services regarding custody issues and sexual abuse allegations.

Dr. Appleton has taught college courses on Adult Survivors of Sexual Abuse, Child Psychopathology, and Professional Ethics. She served five years on the Illinois Psychological Association Ethics Committee. She served on the Illinois Department of Professional Regulation’s Clinical Psychology Licensing and Disciplinary Board for eight years.

In 2007, Dr. Appleton received the Illinois Psychological Association’s award for Outstanding Contribution to the Association, the Profession, and the Community.

Dr. Appleton enjoys reading, travel, hiking, and volunteer work, but especially likes spending time with her family.

Mary L. Ossowski, LCSW

Mary OssowskiMary Ossowski is a Licensed Clinical Social Worker who has been in private practice since 1989. She attended Southern Illinois University for her undergraduate degree and completed a Master’s Degree in Social Work from the University of Wisconsin, Madison, in 1976.

Mary has trained under Pia Mellody, an internationally renowned expert in relational trauma. She has trained under Dr. Patrick Carnes, an expert in treating sex addicts and their partners. Mary provides psychotherapy services to individual adults, adolescents, couples, and families. She has a special interest in relationship counseling and trauma survival.

Mary is married, the mother of two adult children, and is experiencing the joy of being a grandmother. In addition to spending time with her family, she enjoys staying active by traveling, hiking and biking every chance she gets.

Lori K. McKenzie, Psy.D.

Lori McKenzieDr. Lori McKenzie is a Licensed Clinical Psychologist who, in addition to working at the Springfield Psychological Center, works as a consultant for the Ounce of Prevention Fund, the Illinois Department of Children and Family Services, the Illinois School for the Deaf, the Illinois School for the Visually Impaired, and several other agencies that provide residential services to adults with developmental disabilities. She worked previously for the Illinois Department of Human Services as a Rehabilitation Counselor and as a Clinical Psychologist at the School for the Deaf. She is an adjunct psychology professor at Illinois College. Dr. McKenzie has a bachelor’s degree in Deaf Education and a master’s degree in Counseling. Her doctorate was earned from the Adler School of Professional Psychology.

Dr. McKenzie’s clinical interests include depression and anxiety disorders, adjustment to disability, and working with people who are affected by deafness, whether they are children or adults, or family members of the person with a hearing loss. She provides individual psychotherapy with children, adolescents, adults, and couples, and conducts psychological testing. Dr. McKenzie also co-facilitates yoga wellness retreats for women twice yearly, and incorporates alternative wellness techniques with traditional psychotherapy approaches in her clinical practice.

Dr. McKenzie has two daughters who are her pride and joy. She sings in a local Celtic fusion band and in a rock-n-roll cover band with her husband, Bill.

Donald R. Henke, M.S.W., LCSW

Donald HenkeDon Henke is a Licensed Clinical Social Worker who has been counseling individuals and families for 35 years. Don has specialized in working with school-aged children, adolescents, and adults of all ages. He works with individuals as well as couples, families, and groups. He has worked on inpatient psychiatric units and in outpatient counseling. He also has past experience working in child abuse and neglect, both in the investigation and treatment phases, and currently also works in forensics.

Don works with a wide variety of presenting problems from anxiety, depression, stress, and trauma, to adjustment difficulties, marital and divorce counseling, and coaching and wellness, enhancing performance and positive psychology approaches.

Don has taught several college courses in psychology, sociology and counseling in years past, and continues providing various training and inservice programs, as well as numerous crisis intervention stress debriefings throughout central Illinois.

Don has a Bachelor’s degree in Psychology from Quincy College and a Master’s degree in Social Work from St. Louis University, where he studied a variety of clinical and therapy approaches, primarily family and systems therapy and Ericksonian therapy.

Bill McKenzie, MS, LCPC

Bill McKenzieBill McKenzie has a Masters Degree in Human Development Counseling from the University of Illinois at Springfield and became a Licensed Clinical Professional Counselor in 1993. In addition to his counseling practice he is a senior manager at the Ounce of Prevention Fund, working in professional development for child abuse prevention, family support and early childhood education. He previously had a career in pastoral ministry and counseling, taught as an adjunct instructor at University of Illinois at Springfield, and has experience in the Illinois child welfare system and foster care/family preservation field.

Bill’s areas of special interest are in couple’s counseling, lifespan transitions, conflict resolution, depression, anxiety, and general counseling with adolescents and adults. He also has experience and interest in counseling those in faith-related transitions or spiritual crisis.

Bill and his wife Lori have two daughters with whom he enjoys spending free time. He has been a musician for many years in Springfield, Chicago, and Minneapolis, currently playing in several bands with his wife and other local musicians. Being a strong supporter of the arts in the Springfield community, Bill is a board member of the Springfield Area Arts Council. He is an avid student of Joseph Campbell’s work on comparative mythology.

Jenna Reid Yates, Ph.D.

Jenna Reid Yates Jenna Reid Yates, Ph.D., has a Master of Science Degree and Doctoral Degree in Counseling Psychology from the University of Illinois, Urbana-Champaign. She completed her doctoral internship at Illinois State University Student Counseling Services in Normal.

Dr. Yates has worked at a psychological assessment unit of a hospital, the VA Illiana Healthcare System, the Disability Clinic at the University of Illinois, and two University Counseling Centers. She works with individuals across the spectrum of ages providing individual psychotherapy, diagnostic evaluations, and consultation. Dr. Yates is a generalist who utilizes an integrative approach to therapy incorporating psychodynamic, interpersonal, family systems, cognitive behavioral, acceptance and commitment, and mindfulness based approaches. Embedded within these approaches, she also utilizes a multicultural lens. Dr. Yates has a wide range of clinical interests including mood and anxiety disorders, grief and loss, trauma, relationship/interpersonal difficulties, family of origin concerns, identity development/self-esteem, ADHD, diversity and multiculturalism. In addition, she has specialized training in substance use disorders, eating concerns, and comprehensive psychological assessment (i.e., evaluating learning and attention disorders).

Dr. Yates has taught several college psychology courses, such as career theory and practice, and theories of psychotherapy and counseling, at the University of Illinois at Urbana-Champaign. She has published research articles focused on personality, academic achievement, and career readiness.

In her free time, Dr. Yates enjoys spending time with her family, going on walks, biking, traveling, and simply “hanging out!” Laughter is highly valued and incorporated as much as possible into everyday life.

William R. Tennill, MSW, LCSW

Jenna Reid Yates Bill Tennill is a Licensed Clinical Social Worker who has been counseling individuals, couples, and families for over 30 years. He has a Bachelor’s degree in psychology from St. Louis University and received his Master of Social Work Degree, with a specialization in Family Therapy, in 1985 from Washington University in St Louis, Missouri. He has been a member of the Academy of Certified Social Workers (ACSW) since 1988. He has worked in a variety of professional settings including: Inpatient psychiatric units, providing short and long term care to patients and their families; Director of the student counseling center at Illinois College; Professor of social work at MacMurray College, an accredited bachelor of social work program; counselor at alcohol and drug treatment centers, and coordinator of high school drug education programs, providing counseling and educational presentations to students and the community, and sponsoring the S.A.D.D. Club. He has served on the board of directors at the Jacksonville Area Council on Independent Living. He has also served on various community coalitions for the prevention of substance abuse and suicide prevention. Throughout his career, Bill has also maintained an ongoing outpatient private practice serving individuals, families and groups in his community.

Bill’s clinical specialties include depression/mood disorders, anxiety disorders, stress and adjustment reactions, substance abuse and dependency, couples/marital issues, grief and loss, parenting and adolescent behavioral problems and phase of life issues, as well as issues of aging.

Bill and his wife, who is also a Licensed Clinical Social Worker, have two adult children, a son and a daughter. Both of their children are married with children of their own. Bill very much enjoys being a new grandparent and spending time with his family. He also enjoys going on walks and gardening with his wife and playing the piano in his free time.