Clear Insight. Meaningful Change.
Assessments help everyone understand what's needed to optimize success and to boost confidence, self-esteem and motivation.
Clarity That Unlocks Potential
at School, Work, and in Life.
CPBAO-Registered Psychologists | Neurodiversity-Affirming
For anyone feeling chronically overwhelmed, struggling to focus or to get things done, watching their potential go untapped, or feeling misunderstood, we are here for you.
Serving York Region, Halton, Peel, Durham & the Greater Toronto Area
— and virtually across Ontario & Nova Scotia.
Accepted by major insurance providers
Manulife Sun Life Green Shield and most extended health plans
Did You Know?
Why Cornerstone
What Sets Us Apart
- Trusted since 2005. More than two decades serving York Region, the Greater Toronto Area and all of Ontario.
- Flexible scheduling. In-person, virtual, or hybrid.
- A team that listens. Highly trained clinicians and psychometrists who see the whole person.
- Clear, practical reports. Evidence-based, collaborative, and written for you to actually understand and use.
Memberships & Affiliations
College of Psychologists and Behaviour Analysts of Ontario Ontario Association of Mental Health Professionals Canadian Psychological Association Ontario Psychological Association School Neuropsychology Institute American Board of School Neuropsychology American Academy of Pediatric Neuropsychology Autism Ontario Children and Adults with Attention-Deficit/Hyperactivity Disorder Canadian ADHD Resource Alliance Nova Scotia Regulator of Psychology
Our Approach
Leaving "No Stone Unturned" Assessments
Warm, collaborative, and thorough—we go beyond the numbers to understand the person behind the scores and provide clear, practical recommendations.
ADHD/Executive Dysfunctioning
Executive dysfunctioning is a hallmark feature of ADHD but it can exist for other reasons too. Regardless, ADHD is not a simple diagnosis since it may affect or be affected by anxiety, memory, verbal/visual processing as well as other factors, which explains why the need for comprehensive assessments.
Ages 6+ to Adult
3-5 Sessions
In-Person, Virtual, Hybrid
Autism Spectrum Disorder (ASD)
Comprehensive, neurodiversity-affirming autism evaluations for children and adults seeking understanding and support. Since autism falls along a spectrum of mild to severe, many facets of functioning are explored to reflect the uniqueness of every client.
Ages 4+ to Adult
2-6 Sessions
In-Person, Virtual, Hybrid
Learning Disabilities
Evidence-based assessments that identify significantly uneven patterns of processing information that make it especially hard to complete what is expected in an otherwise normally intelligent person. This could include singular or multiple areas (e.g., language, visual processing, memory, reading/dyslexia, writing/dysgraphia, math, etc.), which is why thorough testing is warranted.
Ages 6+ to Adult
3-5 Sessions
In-Person, Virtual, Hybrid
Giftedness Assessment
Very bright individuals have unique needs. While simple gifted assessments that are used to determine eligibility for gifted programming require just a few hours of testing, there are individuals who also have more complicated profiles like ADHD, learning disabilities, autism or other features (known as 'twice-exceptional' or 2E). These students often mask their struggles with high intelligence which means it is especially important to screen for other potential factors which could create some obstacles for them.
Ages 8+ to adult
1-2 Sessions
In-Person, Virtual, Hybrid
Adult Assessment
Whether you need a re-assessment for school or government funding, or you have never been assessed (but feel perplexed, frustrated, or discouraged by learning, productivity, or social challenges), we can help clarify the underlying factors and provide guidance so you can function and perform more optimally.
Ages 16+
3-5 Sessions
In-Person, Virtual, Hybrid
Developmental / Neurodevelopmental Assessments
Evidence-driven testing for individuals with suspected or known intellectual disabilities and/or who have complex neurodevelopmental conditions. Typically, assessments examine cognitive functioning and adaptive behaviour to help determine support needs and inform funding eligibility, educational planning, and life supports across school, work, and community settings. However, those with more complex needs, may require more testing.
Ages 6+ to Adult
1-3 Sessions
In-Person, Virtual, Hybrid
Our Team
Meet the Cornerstone Team
Cornerstone's team is committed to helping clients of all ages reach their full potential. We combine professional expertise with compassion and collaboration to ensure every assessment experience feels supportive, informative, and empowering.
Melissa Cait
Registered Psychologist & Clinic Director
M.A., ABSNP, C.Psych
Vanessa Bao
Registered Psychologist
Ph.D
Marla Cameron
Registered Psychologist
M.A., ABSNP, C.Psych
Noam Erez
Registered Psychologist
M.A., C.Psych
Sheri Gordon
Registered Psychologist
M.Ed., C.Psych
Ashley Rolin
Registered Psychologist
M.A., C.Psych
Yana Kleiman
Registered Psychologist
Dipl.Psych, C.Psych
Andrea Birnbaum
Psychoeducational Consultant
B.A., B.Ed
Joshua Zweig
Psychometrist & Psychoeducational Consultant
M.Psych
Lauren Nusbaum
Manager, Psychometric Services
B.A.
Chiara Capelet
Psychometrist
B.A.Sc
Victoria Mallia
Psychometrist
M.Ed
Cynthia Kleiner
Intake Coordinator
B.Ed
Jordan Cait
Business Manager
Holly Diamond
Office Manager
Ciara Connelly
Psychometrist
B.A.
Ready to Get Started?
Discuss your concerns and learn how a comprehensive assessment can provide the answers you need.
Get In Touch
We're here to help you understand your assessment options. Please call us or send us a message.
Office Hours
Monday - Friday: 9:00 AM - 5:00 PM
Saturday: By appointment
Sunday: By appointment only
Contact Information
Phone: 416-284-5923
Our Location
1 Promenade Circle, Suite 300A
Thornhill, ON L4J 4P8
Cornerstone Psychological Services
Evidence-based psychological and psychoeducational assessments for ages 4+ to adults for ADHD, executive functioning, learning disabilities, autism (ASD), neurodevelopmental, intellectual disabilities, and giftedness with flexible virtual, online and/or hybrid sessions.