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ABOUT

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Neuropsychologist, Certified Autism Specialist, and Director of a Diagnostic Autism Clinic in Peoria, IL

Theresa Regan

I am an adult neuropsychologist with a specialization in brain-behavior relationships. I'm also the mother of an amazing autistic son. Before his diagnosis, I knew the shame that comes from hearing others say, "That would never happen in my house" or "Please have his crying better before returning to the infant program." I received an overwhelming amount of parenting advice, but nothing helped. 

 

It wasn't until my son was 5-years-old that someone took a moment to say, "I hope you know you're a good mom." The truth is, I hadn't known that. I was so grateful to be seen and supported during the confusing journey. It was soon after that my son received a diagnosis of autism and our path became purposeful.

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My working knowledge of brain-behavior relationships merged with my personal journey. I was amazed to interact with adults in my work setting and realize, "This individual is on the spectrum, but they've never received a correct diagnosis!"

I offer individuals the hope and validation of having a correct diagnosis and a direction to move forward. With accurate diagnosis, individuals can understand how they are "wired," have words to express their needs, and finally feel understood by others. With a correct diagnosis, spouses and children of autistic adults can leave behind the feelings of rejection that have accompanied their confusing family interactions. 

I am here to explain complex concepts in plain language. I give you a head start by providing you with the vital information I wish I had known years ago. 

As a neuropsychologist, I've served adults and aged adults for more than 25 years. I'm a Certified Autism Specialist and the Director of the OSF HealthCare Adult Diagnostic Autism Clinic in Peoria, IL. I am the author of Understanding Autism in Adults and Aging Adults and Understanding Autistic Behaviors: Improving Health, Independence, and Well-Being. 

If you're searching for effective strategies to live your best life, message me to request topics for videos and blog posts. Join the new member community to share your struggles and successes with others. 

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Have you explored the website? Check out the many pages dedicated toward clinicians, autistic adults, and family members. You can read articles, find the podcast, or book sessions with Dr. Regan directly through the website. Have additional questions? Feel free to email Dr. Regan and her team using the contact form. 

Contact

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  • Can Dr. Regan suggest a provider in my state?
    Dr. Regan does not maintain a nationwide list of referral options at this time.
  • As a professional clinician, can I schedule an appointment with Dr. Regan?
    Dr. Regan offers various training opportunities for clinicians. Visit the "For Clinicians" page on her website for details on professional consultation appointments, CEU courses, and a free clinicians' group.
  • Is insurance accepted for appointments with Dr. Regan?
    Appointments with Dr. Regan at OSF Saint Francis Medical Center are billed through the hospital, and any insurance accepted by the hospital can be used. Please verify coverage with your insurance provider before the appointment. Video appointments via Dr. Regan's website are self-pay. For more details, visit the video visits page.
  • Does Dr. Regan conduct diagnostic assessments?
    Dr. Regan specializes in autism assessments for adolescents, adults, and older adults, having completed over 1,000 evaluations, including around 400 for females. She performs diagnostic assessments exclusively at OSF Saint Francis Medical Center in Peoria, IL, with a current waitlist of about four years. While she does not offer diagnostic evaluations through her website, she provides one-hour video consultations on topics like communication, relationships, household living, emotional regulation, and work. These can be scheduled via the video visits page.
  • Can I schedule a video visit with Dr. Regan if I am out of state?
    Dr. Regan does not conduct diagnostic evaluations via video sessions. However, you can book a one-hour consultation to discuss daily living topics such as calming anxiety, effective communication, relationship repair, navigating neurodiverse households, and improving organization and productivity. Note that Dr. Regan cannot provide video consultations for individuals in Alaska, California, Guam, Iowa, Hawaii, Louisiana, Massachusetts, Montana, New Mexico, New York, Oregon, countries outside the USA, or Illinois due to contractual obligations with her employer.
  • How can I get on Dr. Regan's evaluation waitlist in Peoria?
    Dr. Regan conducts diagnostic assessments at OSF Saint Francis Medical Center in Peoria, IL. She sees patients aged 14 and older including adolescents, adults, and older adults. She has a four-year waitlist. To be placed on the waitlist, please have your physician call 309-655-7378 for instructions on how to send a referral. Once this is complete, a member of staff will contact you to hold your appointment date.

©2025 by Autism in the Adult

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