Meet Our Staff

Department of Applied Behavior Analysis (ABA) Services

Tiffany Catala, M.S., BCBA, LBA

Supervising BCBA

Tiffany Catala is a dedicated Board Certified Behavior Analyst (BCBA) with more than a decade of experience transforming the lives of children with autism and other developmental needs. Guided by a deep passion for helping young learners thrive, Tiffany has devoted her career to building foundational skills, reducing challenging behaviors, and creating supportive environments where every child has the opportunity to succeed.

Tiffany holds a Master’s degree in Special Education and a Post-Graduate Certification in Applied Behavior Analysis, with a Bachelor’s degree in Psychology concentrated in Child and Family Counseling. This strong educational foundation informs her ability to design individualized, evidence-based interventions tailored to each learner’s unique needs.

Throughout her career, Tiffany has worked in a wide range of settings—including public and private schools, in-home therapy, and clinic-based programs—gaining valuable insight into how to meet children where they are. She specializes in behavior reduction and school readiness, developing programs that empower both children and their families.

Beyond her clinical expertise, Tiffany is an advocate for special education services, guiding families through complex systems to ensure their children have access to the resources they need to thrive. A proud lifelong Maryland resident, she brings her heart for service to every aspect of her work, while also enjoying an active lifestyle as a gym enthusiast, traveler, and avid fan of sporting events and live music.

Christina Dill, M.A., BCBA, LBA

Supervising BCBA

Christina Dill is a compassionate and highly skilled Board-Certified Behavior Analyst (BCBA) with over a decade of experience in the field of Applied Behavior Analysis (ABA). With a Master’s degree in Education and a concentration in ABA from Arizona State University, Christina has dedicated her career to empowering children with autism and developmental differences to reach their fullest potential.

Christina’s approach is deeply client-centered and gentle, built on the belief that every child deserves individualized support to thrive in all areas of life. She specializes in creating tailored interventions designed to promote independence, foster effective communication, and enhance each child’s ability to succeed at home, school, and in their communities. Her work is guided by a passion for building strong, positive relationships with families and helping them navigate the unique challenges of raising a child with autism.

Throughout her career, Christina has been a source of encouragement and advocacy for families, ensuring that every child she serves receives compassionate, evidence-based care. Her dedication to making a meaningful difference in the lives of children and their loved ones has earned her the trust and admiration of the families she works with.

Born and raised in Florida, Christina finds balance and inspiration in her family life. She enjoys spending time with her husband and their three children, exploring new destinations, and relaxing near the water.

Haley Harber, M.S., BCBA, LBA

Supervising BCBA

Haley Harber is a Board Certified Behavior Analyst (BCBA) with nine years of experience dedicated to helping children with Autism reach their full potential. She holds a Master’s degree in Applied Behavior Analysis and Organizational Behavior Management from the Florida Institute of Technology.

Throughout her career, Haley has worked extensively with children in home, school, and clinical settings, tailoring her approach to meet the diverse needs of each child. She believes in the power of collaboration, working closely with families to create individualized treatment plans that foster meaningful progress. As a passionate advocate, she is committed to empowering children on the autism spectrum, helping them develop essential life skills and achieve greater independence.

Originally from West Virginia, Haley has a deep appreciation for travel and enjoys exploring new places. In her free time, she loves spending quality time with her family and her two dogs. Her dedication to the field, combined with her compassionate approach, makes her a trusted professional in the autism community.

Iulietta Panaouris, M.A., BCBA, LBA

Supervising BCBA

Iulietta Panaouris is a dedicated Board-Certified Behavior Analyst (BCBA) with over a decade of experience in the field of Applied Behavior Analysis (ABA). She earned her Bachelor’s degree in Psychology from the University of South Florida and a Master’s degree in Professional Behavior Analysis from the Florida Institute of Technology, building a strong academic foundation for her career in supporting children with autism and their families.

Iulietta’s journey began as a behavior technician, where she discovered her deep passion for working with children and making a meaningful difference in their lives. Over the years, she has served learners of all ages and abilities in diverse settings, gaining a comprehensive understanding of individualized care and family-centered collaboration.

A firm believer in the power of evidence-based practices, Iulietta is committed to designing interventions that foster communication, self-advocacy, and essential life skills. Her mission is to empower young learners with autism to develop independence and confidence, while also supporting families in navigating their child’s developmental journey.

Outside of her professional work, Iulietta enjoys traveling, cooking, and spending quality time with her family. Her warmth, expertise, and dedication to creating positive change make her a trusted advocate and leader in the autism community.

Maurice Lewis, B.S., BCaBA

Supervising BCaBA

Maurice Lewis is a Board Certified Assistant Behavior Analyst (BCaBA) with a Bachelor of Science in Psychology. Initially starting his academic journey as a computer science major, Maurice discovered his passion for behavior analysis through an unexpected role as a Registered Behavior Technician, where he gained five years of hands-on experience. This experience inspired him to pursue certification as a Behavior Analyst.

Outside of his professional endeavors, Maurice enjoys a variety of personal interests, including PC gaming, watching anime, and spending time at the archery range. His diverse hobbies reflect his vibrant personality and dedication to balancing work with personal passions.

Weixing (William) Li, PhD., BCBA, LBA

Supervising BCBA

William is a Board-Certified and Licensed Behavior Analyst with a distinguished background in higher education and scientific research. He earned his undergraduate degree in Chemistry and a PhD in Science from Zhejiang University in China, and later completed a Master of Arts in Applied Behavior Analysis with an emphasis on Autism at Ball State University.

Prior to joining the Global Center for Autism Services, Dr. Li served as a science faculty member at several universities, including The Catholic University of America, the University of the District of Columbia, and Rowan University. He is the author of more than 40 peer-reviewed publications and patents related to the design and synthesis of novel medications. His extensive academic and research experience informs a thoughtful, evidence-based approach to applied behavior analysis across diverse educational and clinical settings.

Outside of his professional work, Dr. Li values balance and well-being and enjoys playing table tennis.

Zhihao Ou, MS, BCBA, LBA

Supervising BCBA

Zhihao Ou is a Board-Certified Behavior Analyst (BCBA) with specialized expertise in autism treatment. He earned his degree from the esteemed Florida Institute of Technology, where he trained under the mentorship of leading experts Dr. David Wilder and Dr. Kimberly Sloman at the Scott Center for Autism Treatment.

He is dedicated to delivering exceptional care through a rigorous adherence to evidence-based practices. His commitment to ongoing professional development ensures he remains at the cutting edge of autism research and therapeutic techniques.

Outside of his professional life, Zhi is an avid traveler and a practitioner of Mixed Martial Arts (MMA). These diverse interests contribute to a well-rounded lifestyle, allowing him to approach his work with renewed energy and a broad perspective.

Jamie Schneider, MA, BCBA, LBA

Supervising BCBA

Jamie Schneider is a Board-Certified Behavior Analyst (BCBA) with a robust background in special education. She earned her Bachelor’s degree in Elementary Education, with a specialization in Special Education, from Lewis-Clark State College. She further advanced her expertise by obtaining a Master’s degree in Special Education with an emphasis on Applied Behavior Analysis from Arizona State University.

Before joining the Global Center for Autism Services, Jamie worked as a special education teacher, supporting students from kindergarten through 12th grade. Her extensive experience in the classroom has deepened her understanding of diverse educational needs and the application of behavior analysis in various settings.

Jamie resides in North Idaho with her husband and three children, where they enjoy life on a mini farm. This personal and professional balance enriches her approach to her work, bringing a grounded and empathetic perspective to her role as a Supervising BCBA.

Samantha Spiezio, M.S., BCBA, LBA

Supervising BCBA

Samantha is a seasoned Board-Certified Behavior Analyst (BCBA) with over a decade of professional experience in education and Applied Behavior Analysis (ABA). She earned her Master’s degree in ABA from Simmons University in Boston, MA, and has also served as an Adjunct Professor at Bay Path University, where she supervised and mentored aspiring behavior analysts.

Throughout her career, Samantha has been deeply committed to supporting children with autism and their families. She has worked across a wide range of settings, including residential programs, clinics, and in-home environments, providing care to children from preschool age through young adulthood. Her passion lies in supporting families during early or first-time autism diagnoses, helping them navigate this new journey with compassion and confidence. Samantha is known for creating safe, supportive environments where both children and their families feel empowered and understood.

A strong advocate of collaborative and individualized care, Samantha embraces Ogden Lindsley’s philosophy that “the learner is always right.” She believes that when a child struggles to learn, it is the responsibility of educators and therapists to adapt their methods, ensuring every child has the opportunity to thrive.

Outside of her professional work, Samantha enjoys reading, running, and hiking with her husband, three stepchildren, and their family dog. Her dedication to evidence-based practices and her deep passion for improving the lives of children with autism make her a trusted leader in her field.

Muhammad Tehseen, EdD., BCBA, LBA

Supervising BCBA

Muhammad Tehseen is a dedicated Board-Certified Behavior Analyst (BCBA) based in Maryland. He holds a specialized post-graduate certification in Applied Behavior Analysis (ABA) from the Florida Institute of Technology, complementing his extensive background in special education.

With over five years of experience working with children on the autism spectrum and related disabilities, Tehseen has honed his skills as a licensed educator. His work is characterized by a deep passion for supporting children from diverse cultural backgrounds. He has developed his clinical expertise and supervisory skills through his association with the Autism Resource Center, focusing on interventions within school settings.

Tehseen is guided by the principles articulated by Dr. Temple Grandin, who said, “I am different, not less,” and Naoki Higashida, who stated, “Everybody has a heart that can be touched by something.” These beliefs underpin his commitment to making a meaningful impact in the lives of neurodivergent children and their families.

Department of Speech and Language Pathology

Amy L. Perkins, MS, CCC-SLP

Coordinating Speech-Language Pathologist

Amy L. Perkins is a skilled Speech-Language Pathologist (SLP) with extensive experience serving diverse populations across multiple states. Her career has taken her through the school systems of Maryland, DC, Michigan, and Georgia as a Traveling Speech Therapist.

Amy earned both her Bachelor’s and Master’s degrees in Communication Sciences and Disorders from Howard University. She has a particular passion for working with preschool and school-aged children, fostering their communication development with dedication and expertise.

Her research interests focus on developmental language disorders in children with Autism Spectrum Disorder (ASD) and the effectiveness of multidisciplinary service models. Amy’s commitment to these areas underscores her ongoing pursuit of innovative and impactful approaches in speech-language pathology.

Josephine Adeoye, M.S., CCC-SLP

Speech-Language Pathologist

Josie is a dedicated Speech-Language Pathologist with a solid academic foundation and a diverse clinical background. She earned her Master’s degree in Speech-Language Pathology from The University of the District of Columbia and completed her undergraduate studies in Speech-Language Pathology and Audiology at Towson University.

With experience spanning both pediatric and adult populations, Josephine has developed a particular passion for working with children with autism. Her interest in this area deepened through her clinical training and subsequent professional roles, allowing her to make a significant impact on her young clients’ lives.

Outside of her professional pursuits, Josephine values quality time with family and friends, delights in exploring museums, and enjoys watching films. Her well-rounded interests reflect her commitment to both her personal and professional growth.

Frances Licia Ladaga, MS, CCC-SLP

Speech-Language Pathologist

Frances Licia Ladaga is a dedicated Speech-Language Pathology Clinical Fellow with a comprehensive academic background and practical experience. She holds a Bachelor’s Degree in Speech-Language Pathology & Audiology and a Master’s Degree in Speech-Language Pathology, both from Towson University.

Frances has accumulated valuable experience working with a diverse age range of clients, from children aged 2 to 16 with speech-sound disorders, language disorders, and autism, to adults aged 30 to 80 with aphasia, motor speech disorders, and cognitive-communication disorders. Her work reflects a broad skill set and a commitment to addressing various communication challenges.

Outside of her professional responsibilities, Frances enjoys reading, watching shows, and spending quality time with family and friends, balancing her career with personal interests that enrich her life.

Juveria B. Thasthahir, M.S., CCC-SLP

Speech-Language Pathologist

Juveria B. Thasthahir is a dedicated Speech-Language Pathologist based in New York, with a Master’s degree in Communicative Sciences and Disorders (Speech-Language Pathology) and a Bachelor’s degree in Advanced Zoology and Biotechnology. Her profound dedication to enhancing communication for individuals with autism is deeply rooted in both personal experiences and professional encounters.

Before pursuing her Master’s degree, Juveria worked as a Behavior Technician, where she developed a strong appreciation for the intersection of behavior analysis and speech-language pathology. This experience solidified her commitment to improving communication skills in the autism spectrum population.

Outside of her professional life, Juveria enjoys a range of personal interests including reading, savoring tea, and traveling with her family, which enriches her well-rounded approach to both her personal and professional endeavors.

Department of Occupational Therapy

Leanne S. Ma, MSOT, OTRL

Occupational Therapist

Leanne S. Ma is a dedicated occupational therapist with Bachelor of Science (Magna Cum Laude) and a Master’s Degree in Occupational Therapy (Magna Cum Laude) from Western Michigan University. With seven years of experience working with patients who have traumatic brain injuries (TBI) and other neurological conditions, Leanne brings a wealth of expertise to her practice.

Leanne is deeply passionate about helping families enhance their quality of life and improve their functional abilities in areas that are most meaningful to them. Her approach to therapy is centered on empowering individuals to achieve their personal goals and live their best lives.

In her personal time, Leanne enjoys the outdoors, playing games, and engaging in craft projects, reflecting her vibrant and creative spirit.

Administration

Salvador E. Tan, Ph.D.

Co-Founder and Chief Executive Officer

Dr. Salvador E. Tan is a seasoned educational leader and the Co-Founder and Chief Executive Officer of our organization. He holds a Bachelor of Science in Education and advanced degrees in Business Administration, Special Education, and Psychology from esteemed institutions in the Philippines. Further enhancing his expertise, Dr. Tan completed postgraduate studies in Leadership and Administration and earned a graduate certificate in Applied Behavior Analysis from Penn State University.

Dr. Tan’s career spans both domestic and international settings, reflecting his extensive experience in General and Special Education. His teaching portfolio includes roles at both undergraduate and graduate levels, showcasing his versatility and depth of knowledge. In the United States, Dr. Tan has taught special education and social skills classes for students with autism. He remains a certified teacher in Special Education, Biology, and Psychology, with additional administrative credentials in Maryland. After a distinguished career, he retired early from the school system to focus on his leadership role within the organization.

Henry E. Tarroza, Ph.D.

Co-Founder & Chief Financial Officer

Dr. Henry E. Tarroza is a distinguished educational leader and the Co-Founder and Chief Financial Officer of our organization. His academic journey includes undergraduate degrees in Elementary Education and Psychology, complemented by both a Master’s and Doctoral degree in Special Education. To further refine his expertise, Dr. Tarroza earned a postgraduate certificate in Applied Behavior Analysis (ABA) from Penn State University, along with a certificate in Human Resource Management and a diploma in Organizational Development.

With over twenty years of experience spanning both corporate and academic realms, Dr. Tarroza has built a diverse and impressive career. His teaching experience ranges from kindergarten through graduate level, demonstrating his broad and deep knowledge across various educational stages. In Maryland, he holds certifications in Special Education, General Education, and Psychology.

Currently, Dr. Tarroza focuses on teaching social skills within an autism high school program, where he leverages his extensive knowledge and skills to support students with unique needs. His leadership and vast experience in both educational and organizational contexts underscore his commitment to excellence and innovation in the field of education.

Mary-Claire “Marcy” DiMiceli, MS, BCBA, LBA.

Director of Operations

Mary-Claire “Marcy” DiMiceli is a respected Graduate Adjunct Professor of Applied Behavior Analysis (ABA) and a Board Certified Behavior Analyst (BCBA). She holds dual master’s degrees in General and Special Education from Fordham University, which provides her with a robust foundation in both disciplines.

With over 22 years of experience in ABA, Marcy has demonstrated exceptional skill and dedication across a broad spectrum of settings, working with clients of all ages and abilities. Her extensive career reflects a deep commitment to advancing behavior analysis practices and enhancing outcomes for individuals with diverse needs.

Beyond her professional achievements, Marcy is an avid traveler and yoga enthusiast, and enjoys spending quality time with her family. Her dedication to both her field and personal interests underscores her holistic approach to life and work.

Madison Andreu, MA, BCBA, LBA

Clinical Quality Director

Madison Andreu is a distinguished Clinical Quality Director and Board Certified Behavior Analyst (BCBA) with a strong academic and professional background in Applied Behavior Analysis (ABA). She earned her Bachelor of Science in Behavioral Healthcare, with a minor in ABA, and a Master of Arts in Behavior Analysis, both from the University of South Florida. Furthering her expertise, Madison has also completed a certification in Positive Behavior Supports and a post-graduate certificate in Organizational Behavior Management from the Florida Institute of Technology.

With over a decade of experience in the field of ABA, Madison has proven herself as an expert in elevating clinical practices and maintaining high standards of service delivery. Her career includes significant teaching experience, which has deepened her understanding and application of behavior analysis principles.

Madison’s extensive experience and advanced credentials reflect her commitment to improving the quality of ABA services and her leadership in implementing effective and impactful behavioral interventions.

Aldrin Tan, MS, BCBA, LBA

Center Director

Aldrin Tan is a highly regarded Center Director and Board Certified Behavior Analyst (BCBA) with a Master of Science in Applied Behavior Analysis from The Chicago School of Professional Psychology, where he graduated with academic distinction. He completed his undergraduate studies in Psychology at Ateneo de Zamboanga University in the Philippines

Aldrin brings extensive experience in Applied Behavior Analysis, with a particular focus on working with children on the autism spectrum. His expertise encompasses establishing verbal communication, fostering cooperative behaviors, and managing problem behaviors. His comprehensive training and practical experience highlight his dedication to enhancing the effectiveness of behavioral interventions.

Fluent in Tagalog and English, and conversational in Spanish, Aldrin’s multilingual skills enable him to engage effectively with a diverse range of families and communities. Outside of his professional role, he enjoys singing karaoke, reflecting his vibrant personality and commitment to a well-rounded and fulfilling lifestyle.

Tajoi J. Dawkins, M.A., BCBA, LBA

Assistant Center Director

Tajoi J. Dawkins is a seasoned Board Certified Behavior Analyst (BCBA) licensed in Maryland. She holds a Bachelor of Health Science with a specialization in Rehabilitative Services from the University of Florida and a Master of Exceptional Student Education from the University of West Florida.

With over a decade of experience in Applied Behavior Analysis, inpatient behavioral and mental health services, and child welfare, Tajoi has developed a robust expertise in her field. Her Jamaican heritage enriches her practice, allowing her to offer culturally competent support to families within the Caribbean diaspora.

Outside of her professional pursuits, Tajoi enjoys traveling and has a passion for landscape photography, reflecting her appreciation for both exploration and creative expression.

Jesenia Diaz, M.S.

Scheduler

Jes is a dedicated scheduler with a strong background in exercise science, healthcare administration, and applied behavior analysis. She holds a Bachelor of Science in Exercise Science from Towson University and a Master’s degree in Applied Behavior Analysis from Purdue Global University.

Jes began her career as a receptionist in a physical therapy office, where her organizational skills and commitment to efficiency quickly earned her a promotion to office manager. In this role, she gained extensive experience in healthcare operations, scheduling, and patient coordination

Her journey with Global Center for Autism Services (GCAS) began as an office manager, where she played a crucial role in ensuring the smooth operation of administrative functions. Inspired by her growing interest in behavioral therapy and client services, she decided to pursue her master’s degree in Applied Behavior Analysis.

Now serving as the scheduler for GCAS, Jes is responsible for coordinating client sessions, managing schedules for Registered Behavior Technicians (RBTs), and ensuring a seamless scheduling process. Her attention to detail and ability to balance multiple priorities allow her to effectively align client needs with staff availability, helping to optimize therapy services and enhance the overall client experience.

Passionate about helping families and supporting individuals with autism, Jes takes pride in her role, ensuring that services are delivered efficiently and effectively while maintaining a client-centered approach.

Yessica Cabezas, BS

Branch Administrator (Laurel)

Yessica serves as the Branch Administrator at Global Center for Autism Services, where she plays a vital role in overseeing daily operations and ensuring a supportive, welcoming environment for both staff and families. Known for her attention to detail and compassionate leadership, Yessica helps create a space where children with autism and their families feel comfortable and valued from the moment they arrive.

Her commitment to supporting children and families extends beyond her administrative role. Yessica is currently pursuing dual Master’s degrees in Mental Health Counseling and School Counseling, reflecting her dedication to expanding her expertise and deepening her ability to serve diverse communities. She is particularly passionate about breaking down stigmas surrounding mental health and ensuring families have access to resources that empower them to thrive.

Outside of her professional life, Yessica enjoys running, practicing Pilates, and spending quality time with her family. She remains deeply motivated by her studies and aspires to one day work directly as a counselor, continuing her mission to make a meaningful impact on children with autism and their families.