My Background
I am a psychologist in New York State with over ten years of clinical experience providing psychotherapy to children, adolescents, adults, and families, as well as neuropsychological evaluations for children, adolescents, and adults.
After earning my bachelor’s degree in psychology at The American University with an emphasis in neuroscience, I began my career as a teacher at an alternative school. That experience clarified how essential individualized approaches to care can be—whether in education, therapy, or assessment—particularly for those who are struggling. This work sparked and shaped my two clinical passions: psychotherapy and neuropsychological testing. I went on to earn my Master’s degree in Mental Health Counseling from the University of Miami and my Ph.D. from the Derner School of Psychological Services at Adelphi University.
I have worked in a range of treatment settings, including a juvenile adjudication program, community mental health clinics, inpatient and outpatient psychiatric units in city hospitals, and Memorial Sloan Kettering Cancer Center. I have advanced training in Alliance-Focused Therapy (AFT) and Attachment-Based Family Therapy (ABFT). My early research examined identity development in twins, and later work focused on the therapeutic process within attachment-based treatment for adolescents. I have advanced training in psychological and neuropsychological assessment, with particular focus on comprehensive evaluations of complex developmental disorders like learning disabilities, ADHD, autism, and mood disorders. In addition to my clinical work, I have instructed undergraduate and graduate-level courses in Developmental Psychology and Neuropsychological Assessment.
In my clinical work, I trust in people’s ability to communicate their authentic experience when given the right conditions. I often incorporate imagery, somatic awareness, and humor to help deepen understanding and connection to oneself. I consider myself very fortunate to be able to do this work every day.
Professional Affiliations
Mind Bridges Collective - Assessment Consultant and Supervisor
The Galynker Center for Bipolar Disorder - Assessor
Attachment-Based Family Therapy (ABFT) International - ABFT Researcher
Publications
Cassell, S. & Diamond, G. (In Press).Adolescent attachment associated with alliance ruptures in attachment- based family therapy: frequence, type and timing.
Cassell, S. & Diamond, G. (2022). Rupture and Repair in Psychotherapy with Adolescents. In J.C. Muran & C. Eubanks (Eds.) Rupture and Repair in Psychotherapy.
Urmanche, A, Olivera, J, Cassell, S., Goncalves, M., Eubanks, C., & Muran, J. (2019, June). Ambivalence and alliance ruptures in the treatment for substance use disorders: A case study. Panel presented at the Society for the Exploration of Psychotherapy Integration, Lisbon, Portugal.
Cassell, S. & Gray, J. (2011, May). Identity Development and Ego Differentiation in Identical and Fraternal Same-sex twins. Talk presented at the American University Research Conference, Washington, DC.