About Ascend Autism

Ascend Autism is elevating the outcomes of children diagnosed with autism spectrum disorder (ASD).

Ascend Autism was founded by a highly qualified team of healthcare operators and Board Certified Behavior Analysts (BCBA). With over a decade of experience, Ascend Autism provides children and families with evidence-based ABA treatment in a compassionate and safe environment.

Importantly, all interventions used at Ascend Autism ABA Therapy Center are rooted in evidence-based practices (EBPs). This simply means the intervention has been tested in scientific studies and published in scientific journals. The results show these intervention practices are more helpful and produce better outcomes for children with autism spectrum disorder. We are focused on the continued success of each child and supporting every family on their individualized journey.

Our autism spectrum disorder treatment programs for children include:

Helping Children And Families Succeed!

Meet Our Caring, Compassionate Team

At Ascend Autism, we understand that choosing the right care for your child is a deeply personal and important decision.

Our team is composed of experienced, caring professionals—each dedicated to providing the highest-quality treatment for your precious child. With a breadth of skills and a shared commitment to helping children on the spectrum flourish, you can rest assured that your child will grow in a safe, supportive environment.

Emily Tiemann

Sharon Dudhnath-Grotsky

M.S., BCBA, LBA
Clinical Director

Sharon is a Board Certified Behavior Analyst (BCBA) and a Licensed Behavior Analyst (LBA) for both New York and Connecticut. As Clinical Director, Sharon provides supervision and leadership for all clinical personnel and oversight for all clinical operations at Ascend Autism.

She has over ten years of clinical experience in applied behavior analysis as a BCBA and Clinical Director in New York, Connecticut, and California, working with several ABA providers, including Achieve Beyond, Pacific Child and Family Associates, and Center for Learning and Autism Support Services, Inc.

Sharon received her BA in psychology from Stony Brook University. She completed graduate work in Counseling Psychology (MS) from Pace University. She attained her MA in Industrial/Organizational Psychology from the Chicago School of Professional Psychology.

Outside of work, Sharon enjoys spending time with family and friends, traveling, and reading.

Caitlyn Collins

Caitlyn is our Operations Manager in Nashville. She holds a Bachelor of Science from the University of Rhode Island College of Business and has eight years of experience in operational management. Caitlyn previously worked in the fitness and corporate retail sectors.

Outside work, Caitlyn enjoys traveling, attending concerts, and spending time with her family.

Nathalie Spiesser

M.S., BCBA, LBA
Center Director

Nathalie is Center Director at Ascend Autism in Nashville. Nathelie brings nearly two decades of experience working with children. She hold a Master’s degree in Special Education from Penn State and has dedicated her career to supporting children with ASD.

Before becoming a BCBA, Nathalie spent three years as an RBT, solidifying her understanding of ABA therapy and the day-to-day needs of the children and families she serves.

Prior to joining the Ascend Autism Team, Nathalie built her professional foundation in Chattanooga, where she gained experience across a variety of settings. She later moved to Nashville specifically to continue her career with Ascend and help expand the high-quality, compassionate center-based ABA services. Outside of work, Nathalie enjoys spending time at home with her family, reading a good book, and starting her day with a great cup of coffee.

Ariel Magowan

Ariel is the Operations Manager at Ascend Autism’s Westport, CT center, where she oversees the day-to-day operations to ensure a supportive and efficient environment for clients, families, and staff. She holds a bachelor’s degree in psychology from Sacred Heart University and a master’s degree in human services from Albertus Magnus College.

Before joining Ascend, Ariel gained experience working with children in kindergarten through 12th grade across a variety of school settings. Her longstanding passion for helping others drives her commitment to creating a positive, safe, and engaging space where children can thrive.

Ariel plays a key role in team development, ensuring that staff are well-trained, supported, and equipped to meet the individualized needs of each child. Her compassionate leadership and dedication make her a valued member of the Ascend team and help ensure that every family feels confident and cared for from the moment they walk through the door.

Katie Crowley

M.S., BCBA, LBA
Center Director

Katie is a Board Certified Behavior Analyst (BCBA) and Licensed Behavior Analyst (LBA), serving as the Center Director at Ascend Autism’s Westport, CT location. She has been with Ascend for over five years, beginning her career as a behavior technician and advancing through roles that deepened her passion for ABA and its life-changing impact on children and families.

Katie earned her bachelor’s degree in psychology from Quinnipiac University and her master’s degree in Applied Behavior Analysis and Autism from Russell Sage College. Prior to becoming Center Director, she worked as both a BT and BCBA, gaining valuable hands-on experience in providing individualized support and seeing firsthand the progress made by clients and their families.

Katie’s dedication to the field was sparked early on through babysitting, volunteering, and supporting children with special needs alongside her mother, a teaching assistant. Today, she leads with compassion and collaboration, committed to fostering a nurturing and effective therapeutic environment for the children and families she serves.

Gráinne Farrelly

Gráinne is the Operations Manager at Ascend Autism’s Latham, NY center, where she supports clinical and administrative operations to help ensure a smooth and supportive experience for the children and families we serve.

Before joining Ascend, Gráinne worked in behavioral and mental health services in Pennsylvania, providing counseling to children, adolescents, and their families. She brings a strong foundation in client care and operational support to her role.

Originally from Ireland, Gráinne moved to the United States in 2016. She holds a degree from the University of the West of Scotland.

In her free time, Gráinne enjoys running, traveling home to Derry to visit family, and spending time with her partner and their cat, Maksim.

Emily Tiemann

M.S., BCBA, LBA
Center Director

Emily earned her Master’s Degree in Applied Behavior Analysis and Autism from The Sage Colleges. She has spent the past 15 years supporting individuals with developmental disabilities and their families across home, school, clinic, and community settings.

Emily is dedicated to the compassionate treatment of severe behaviors and teaching client’s self-advocacy skills.

When she is not working, you can find her baking, enjoying the outdoors, or cheering on her favorite WNBA teams.

Bri LaVoie

Bri is the Operations Manager at Ascend Autism’s Hawthorne center. She brings over 20 years of experience working directly with children of all ages. She is a dedicated administrator with a strong track record of fostering family and staff engagement through successful center-wide events and programming.

Bri holds a master’s degree in education from Northcentral University, where she focused her studies on behavioral science. Her educational background and hands-on experience support her work in creating a welcoming, organized environment for families and staff alike.

Outside of work, Bri enjoys dancing, gardening, and camping with her daughter and husband.

Alexa Hernandez

Alexa earned her Master of Science in Industrial Organizational Psychology from Fairfield University in May 2025, where she discovered her passion for understanding what helps people thrive at work, in their relationships, and in their daily lives. She is deeply committed to creating uplifting, supportive cultures and loves finding ways to bring out the best in the people around her.

She has a natural talent for working with children, offering them encouragement, structure, and a space to grow with confidence. Alexa finds joy in helping young people discover their strengths and supporting them through each new milestone.

In her free time, Alexa enjoys watching movies, spending meaningful time with her family, and being actively involved in her nieces’ lives. She especially loves helping them train and condition for lacrosse, offering support, motivation, and plenty of cheering from the sidelines.

Caylin Raju

M.S., BCBA, LBA
Center Director

Caylin is the Center Director for Ascend Autism in Farmington, CT, and has more than a decade of experience supporting children on the autism spectrum. She has dedicated her career to helping children with ASD and their families thrive.

Caylin earned her master’s degree in Applied Behavior Analysis from Ball State University. She began her career in Early Intervention, but discovered her passion for autism services while working closely with a client transitioning out of the program. Before becoming a center-based BCBA, Caylin gained extensive experience as an RBT across school, in-home, and center-based settings.

Outside of work, Caylin enjoys spending time with her husband and twins, and visiting local wineries.

About Ascend Autism

Ascend Autism is elevating the outcomes of children diagnosed with autism spectrum disorder (ASD).

Helping Children And Families Succeed!

Meet Our Caring, Compassionate Team

Emily Tiemann

Sharon Dudhnath-Grotsky

M.S., BCBA, LBA Clinical Director

Caitlyn Collins

Nathalie Spiesser

M.S., BCBA, LBACenter Director

Ariel Magowan

Katie Crowley

M.S., BCBA, LBACenter Director

Gráinne Farrelly

Emily Tiemann

M.S., BCBA, LBACenter Director

Bri LaVoie

Alexa Hernandez

Caylin Raju

M.S., BCBA, LBACenter Director

877.323.8668

M.S., BCBA, LBA
Clinical Director

M.S., BCBA, LBA
Center Director

M.S., BCBA, LBA
Center Director

M.S., BCBA, LBA
Center Director

M.S., BCBA, LBA
Center Director