Meet Our Team


Crystal Ciszek, Director of Operations

Crystal is currently the Director of Operations for the Autism Therapy Group. She has over ten years of experience working with children with disabilities. She started her career as an instructional assistant during a summer school program in 2005 and quickly learned that this was her passion. She has provided special education services in a wide variety of settings: public schools, private schools, therapeutic day schools, clinical facilities, and in-home. Crystal is a licensed Learning Behavior Specialist from Northern Illinois University, highly qualified in reading and language arts, and holds a current certification as a Registered Behavior Technician.

During her first years working as a special education teacher at a private not-for-profit organization, she learned the principals of Applied Behavior Analysis (ABA). The faculty trained her how to utilize these principals in an educational setting, embed them into various curriculums, and carry these skills over to generalized environments. The progress she saw within those children, was like none she had ever seen before. Data was recorded day by day, trends were reviewed weekly, necessary updates were implemented immediately, and ultimately the children were blossoming.

Since then, she has dedicated herself exclusively to the therapeutic aspect of ABA. She has served as a private practice clinician, supporting students in daycares, preschools, and homes. Crystal understands the necessities behind great communication and a strong team.


Maria Guzman, MS, Office Manager

Maria Guzman is currently working as the Office Manager at the Autism Therapy Group.  She started at ATG as a part-time Behavioral Therapist and soon became a part-time Office Assistant. Maria has been with the company for a little over three years and has a Master of Science in Psychology with a concentration in Applied Behavior Analysis from Kaplan University. Since then, she has dedicated herself to the office and has enjoyed watching ATG grow from behind the scenes. She takes pride in the teams that she helps build; Ensuring that every one of our clients has the team and quality services they deserve.



 Ashley Nemazee, MA, BCBA

Ashley Nemazee is a Board-Certified Behavior Analyst with a master’s certification in Applied Behavior Analysis from the University of North Texas, a master’s in Human Behavior from National University, and a Bachelor’s in Applied Psychology from the University of Illinois in Chicago. Ashley was born and raised in Chicago and began providing direct services to individuals diagnosed with autism spectrum disorders in 2008. She has provided and supervised home-based ABA programs, school shadowing programs, as well as parent and school staff training for clients between the ages of 2 and 19 years of age with varying degrees of diagnosis severity.


Lisa Guerrero, M.Ed, BCBA

Lisa is a Board-Certified Behavior Analyst, a Certified Special Education teacher, as well as a Licensed Behavior Analyst in Texas. Lisa Guerrero received her Bachelor’s degree in Sociology from The University of Texas at San Antonio and her Master’s degree in Educational Leadership from Lamar University. She also completed her graduate coursework in Applied Behavior Analysis from The University of North Texas.

Lisa has a total of 15 years of experience working in the public-school system. She worked as a special education teacher for 8 years with elementary and middle school students diagnosed with Autism and other developmental disabilities. The next 7 years were spent as an Autism/Behavior Specialist working with PreK through high school students.

Since becoming a BCBA in 2014, Lisa had the opportunity to utilize her ABA training with individuals in the private sector. Lisa has enjoyed working with individuals ranging from 18 months to 70 years with varying levels of severity. She continues to expand her knowledge in ABA, but currently enjoys training others to work with learners focusing on early intervention, reducing severe challenging behaviors and increasing verbal behaviors.


Karyn Olszak, Ed.S., BCBA

Karyn received her Bachelor of Science degree in 2006 from Bradley University and an Educational Specialist degree in 2011 from The Chicago School of Professional Psychology.   She earned her ABA certification through Florida Institute of Technology and became a Board-Certified Behavior Analyst in May 2018. Karyn has worked as a school psychologist, autism coach, and BCBA in school districts where she assesses students, engages in problem solving with teams, and coaches around ABA instructional methodologies.  She is passionate about cultivating professional, prepared teams to better serve children with a variety of ability levels.

Karyn has over a decade of experience working in a multitude of ABA settings: home, clinic, schools, and summer camps/recreational community outings. Karyn has working experiences with individuals from ages two up through young adults; she takes great pride in parent training and celebrating successes with families!

Karyn enjoys spending time with family and friends in her free time. She loves taking her dog, Paul, to the beach and park, as well as trying new restaurants, going to neighborhood festivals, and working out.


Christine Koessl, MS, BCBA

Christine is a Board-Certified Behavior Analyst who graduated from The Chicago School of Professional Psychology with a Master’s Degree in Applied Behavior Analysis.  Christine received her Bachelor’s degree in Psychology from Carthage College.  Christine has worked with children and adolescents diagnosed with Autism and other development disabilities since 2012.   Christine has worked with adults diagnosed with developmental disabilities since 2016.  Christine has worked in clinic, residential, and in-home settings.  Christine’s graduate work focused on healthy eating habits in children and adolescents.



Brooke Belling, MS, BCBA

Brooke received her Bachelor of Arts in Early Childhood Education in 2011 from St. Ambrose University and her Master of Science in Applied Behavior Analysis in 2017 from The Chicago School of Professional Psychology. While earning her graduate degree, Brooke worked for an in-home ABA agency to obtain practicum hours.

Once board certified by the BACB in 2017, Brooke continued to advance her career working as a Board-Certified Behavior Analyst for an in-home ABA agency. She has worked with a wide range of individuals, from Early Intervention clients as young as age 2, through transition clients aged into their 20’s. Brooke has been very fortunate to have graduated multiple early learners from ABA therapy and witness their integration into general education placements and perform like typically developing peers the same age.

Brooke enjoys spending time with family, friends, and her dog, Ari! She also provides respite services in her free time to maintain relationships with adults on the spectrum.


Matt Nordman, MA, BCBA

Matt received his Bachelor of Arts in 2012 from the University of Illinois (Urbana-Champaign), and his Master of Arts in Applied Behavior Analysis in 2015 from Ball State University.  During completion of graduate school, he gained experience in a therapeutic day school while working as an ABA therapist for an in-home agency.

Once Matt finished school and became board certified by the BACB in 2015, he served as supervisor of a behavior department at a day program for adults for two years while continuing to work for an in-home ABA agency. For the last year Matt has solely worked with children. Matt enjoys working with individuals across multiple age ranges, having provided services to clients ranging from 18 months to 80 years old.

Matt enjoys spending time with his family, friends, and dog whenever possible. In his free time, he likes to play basketball, watch movies, explore new restaurants in Chicagoland, and go hiking with his Bloodhound, Watson.


Alyssa Figueroa, MA, BCBA

Alyssa Figueroa is a Board-Certified Behavior Analyst (BCBA). She graduated with her Master’s in Applied Behavior Analysis from Aurora University. Alyssa has worked in the field of ABA for 5 years in a variety of settings. Her experience includes working in adult day and residential programs, clinics, and in-home settings. Alyssa has also worked with a wide range of clients from the ages of 3-70. Her focus is on conducting functional assessments to create function-based programming to promote skill acquisition and independence amongst her clientele.



Carrie Mochel, MA, BCBA

Carrie has been working with individuals with Autism since 2011 in both Autism research and ABA therapy. She currently holds a Master’s degree in Applied Behavior Analysis from Ball State University and several certificates in Autism and behavior studies. She has worked with individuals 2-18, both in clinic and in-home settings all over Chicago and the Western Suburbs. Her areas of interest are communication and toilet training. In the future, she hopes to obtain a second Master’s degree and use her behavior analytic skills to assist veterans and their families. In her free time, she spends time with family and friends and loves to travel. She is looking forward to seeing her clients progress and building relationships with families.


Tyler Holt, M.Ed., BCBA

Tyler is a Board-Certified Behavior Analyst, was a Certified Special Education teacher, and is Licensed Behavior Analyst in Texas. Tyler received his bachelor’s degree in Psychology from The University of Iowa and his master’s degree in Special Education with concentrations in ABA and Emotional and Behavioral Disorders from Texas State University in San Marcos, Texas.

Since 2009, Tyler has worked as a certified Special Education Teacher, and a Behavior Specialist for treatment centers, clinics, juvenile facilities and State Supported Living Centers.  Tyler became a BCBA in 2014.  Tyler has worked in the community as well and his areas of interest are crisis intervention, functional communication training and embedded Motivating Operations.


Maria Koehler, RBT

My name is Maria Koehler and I am a Registered Behavior Technician for the Autism Therapy Group. I have been married for almost 19 years and have two children. My son is 17 and my daughter is 15. We have lived in Del Rio, Texas for a little over ten years now and we love it here. I have been with ATG for three and a half years.  Before starting with ATG I taught second grade for 5 years. I enjoy working with children and it is very rewarding helping them meet their goals. In my free time, I enjoy shopping and spending time with my friends and family.



Lorraine Smith, Insurance Specialist

I have been with the Autism Therapy Group since 2015 and I am passionate about my career in medical billing and collections. I hold a bachelor’s degree in Healthcare Management and an associate degree in Accounting. I bring over 20 years of experience from the hospital, home health, and physicians offices. Medical billings and collections are both area that require an eye for fine details, which I enjoy! In my spare time with my family, I love bowling, dancing and going to the spa. I am glad to be a part of a team that strives to help children be the best they can be!