Professional Staff

Members of the professional staff at the Oakville Centre for Cognitive Therapy are all either doctoral-level psychologists registered with the College of Psychologists of Ontario, or doctoral candidates working under the direct supervision of a registered psychologist. With rigorous post-secondary education and training typically spanning 10-12 years, the Centre's clinicians are experts in the assessment of psychological difficulties and in the provision of evidence-based cognitive behavioural treatment services to children, adolescents, adults, couples and families.


  • Stephen R. Swallow, Ph.D., C. Psych.

    Stephen SwallowDr. Swallow is the founder and director of the OCCT. His professional experience includes work on the Cognitive Behaviour Therapy Unit at the Centre for Addiction and Mental Health (CAMH) and Assistant Professor of Psychiatry in the Faculty of Medicine at the University of Toronto. He has maintained a private practice in clinical and health psychology in Oakville since 1994. A founding member of the Canadian Association of Cognitive and Behavioural Therapies (CACBT) and a CACBT-certified cognitive behaviour therapist, Dr. Swallow has a special interest in CBT for depression, anxiety, couples problems, and stress-related health difficulties.

  • Robert Ferguson, Ph.D., C. Psych.

    Rob FergusonDr. Ferguson has worked at the Oakville Centre for Cognitive Therapy (OCCT) since 2008. As the OCCT's Clinical Director, he oversees many of the Centre's day-to-day clinical activities. In his own work with clients, he provides assessment and CBT services for adolescents, adults, and couples. He also supervises psychologists in the final stages of their registration for autonomous practice. Dr. Ferguson is both a founding member of the Canadian Association of Cognitive and Behavioural Therapies (CACBT), and a CACBT-certified provider of cognitive behavioural therapy. Prior professional experience includes positions within St. Joseph's Healthcare (Anxiety Treatment and Research Centre, Eating Disorders Program, and Forensic Service), Counselling and Psychological Services at the University of Michigan, a private practice in Windsor, Psychological Services Centre at the University of Windsor, and the Anxiety Disorders Clinic at the Centre for Addiction and Mental Health. Dr. Ferguson is particularly interested in the treatment of anxiety disorders, depression, self-esteem issues, anger management, stress-related difficulties, chronic pain management, and body image concerns.

  • Nina Laugesen, Ph.D., C. Psych.

    Nina LaugesenDr. Laugesen is the OCCT's Director of Child and Youth Services. She has held positions at the Anxiety Research and Treatment Centre, the Mood Disorders Service, and the Schizophrenia & Mental Health Rehabilitation Services at St. Joseph's Healthcare in Hamilton.  She has also worked at the Chedoke Child and Family Centre at McMaster  Children's Hospital.  Dr. Laugesen provides a variety of assessment and treatment services for children, adolescents, adults and families in both French and English.  She has a special interest in the application of CBT and DBT to the treatment of young people with anxiety, depression and behavioural problems, and in child management training for parents.

  • Andrea Peterman, Ph.D., C. Psych.

    Andrea PetermanDr. Peterman has held positions at the Anxiety Treatment and Research Centre, the Mood Disorders Service, and the Eating Disorders Program at St. Joseph’s Healthcare in Hamilton. She has also worked for Hanrahan Youth Services in Brampton, the ADHD Clinic at the Scarborough Grace Hospital, and in the Anxiety Disorders Clinic at the Centre for Addiction and Mental Health in Toronto. A CACBT-certified cognitive behaviour therapist, Dr. Peterman has a special interest in the application of CBT in her work with adolescents and adults presenting with anxiety, depression, and eating disorders.

  • Samantha Waxman, Ph.D., C. Psych.

    Samantha WaxmanDr. Waxman is a registered psychologist, practicing in the areas of clinical, health, and counselling psychology. She is a member of the Canadian Association of Cognitive and Behavioural Therapies (CACBT) and is also a CACBT-certified cognitive behaviour therapist. Dr. Waxman completed her PhD in clinical psychology at Queen's University and a clinical residency at The Ottawa Hospital. Dr. Waxman offers treatment for mood and anxiety disorders, stress-related difficulties, relationship/couple issues, sexual dysfunction, and management of chronic illness/disability. She has a particular interest in working with perinatal (pregnancy and postpartum) issues (e.g., depression, anxiety) and helping with the adjustment to parenthood. Dr. Waxman has also completed a specialized certificate in maternal mental health.

  • Giovanni Foti, Ph.D., C. Psych.

    Giovanni FotiDr. Foti has held positions at Hamilton Health Sciences Centre in the Chedoke Child Youth and Family Program, at the Centre for Addiction and Mental Health in the Gender Identity Service and Adolescent Service. Dr. Foti provides assessment and treatment services for children, adolescents (including high-risk youth), and families. He has a special interest in using CBT to treat young people with mood, anxiety, and behaviour issues. He also offers child management training to parents.

  • Justin M. Mattina, Ph.D., C. Psych.

    Justin MattinaDr. Mattina’s recent professional experience includes positions at the Psychological Trauma Program and the Anxiety Disorders Clinic within the Mood and Anxiety Program at the Centre for Addiction and Mental Health (CAMH) in Toronto. He has also held positions at the Clinical Research Laboratory specializing in the treatment of depression at the CAMH, as well as at the McMaster University Centre for Student Development Counselling Clinic. Dr. Mattina’s primary theoretical orientation is cognitive behavioural therapy (CBT) for adults. He has specialized in the assessment, treatment and facilitation of return to work efforts for clients who have experienced a psychological and/or physical trauma within the workplace. He also has experience in the assessment and treatment of various anxiety disorders (e.g., obsessive compulsive disorder, social phobia and panic disorder), depression and coping with physical pain and disability.

  • Kristen Adams, Ph.D., C. Psych.

    Kristen AdamsDr. Adams has worked in private practice settings for the last decade treating couples as well as individual concerns such as depression, anxiety, life transitions, divorce, bereavement, and relationship/ interpersonal difficulties. Her clinical training included placements at the CAMH's Affective Disorders Unit and the Sunnybrook Hospital's Short-term Psychotherapy Unit. Dr. Adams has a specific interest in working with couples using emotionally focused therapy (EFT). She participated as a therapist in Dr. Leslie Greenberg's research project about resolution of couples' emotional injuries and has also authored a paper on forgiveness processes in couples.

  • Mariyam Ahmed, Ph.D., C. Psych.

    Mariyam AhmedDr. Ahmed's recent professional experience includes positions at the Anxiety Treatment and Research Centre, Mood Disorders Program and Eating Disorders Program at St. Joseph's Healthcare in Hamilton.  She has also received training at the Cognitive Behaviour Therapy Clinic at the Centre for Addiction and Mental Health (CAMH) in Toronto.  Dr. Ahmed has a special interest in the application of CBT to the treatment of anxiety and mood disorders, relationship concerns and interpersonal difficulties.  She provides assessment and treatment services for adults, adolescents and couples.  Dr.  Ahmed is fluent in Urdu and Hindi and can offer services in these languages.

  • Susan Sergeant, Ph.D., C. Psych.

    Susan SergeantDr. Sergeant's recent professional experiences include positions at the Centre for Mental Health Research and University of Waterloo Counselling and Psychological Services, the Work, Stress, and Health Program at CAMH, the York University Anxiety Research Lab, and the Vanier Centre for Women and Maplehurst Correctional Complex. She provides assessment and treatment services to adults and adolescents experiencing difficulties related to mood, anxiety, stress, interpersonal issues, eating disorders, chronic pain, and personality problems. In her work with patients, Dr. Sergeant draws on a number of empirically-supported CBT modalities including acceptance and commitment therapy (ACT), emotion-focused therapy (EFT), dialectical behaviour therapy (DBT), and interpersonal therapy.

  • Gayle Goldstein, Ph.D., C. Psych.

    Gayle GoldsteinDr. Goldstein completed her Ph.D. in the clinical-developmental psychology program at York University. She has held positions at Reach Out Centre for Kids (ROCK) and Child and Adolescent Services in Hamilton. She completed her doctoral internship at PAH! Mental Health Services and the Provincial Schools Branch providing both assessment and therapy services. In addition, Dr. Goldstein has worked for several Ontario school boards providing assessment services. Over the last decade Dr. Goldstein has been working in private practice with children, adolescents, adults and families who are experiencing a wide range of mood, anxiety, behavioural and family issues. Dr. Goldstein has a specific interest in working with individuals who have an Autism Spectrum Disorder and/or who are deaf and hard-of-hearing—and their families. She is fluent in American Sign Language.

  • Dan Zdzieborski, Ph.D., C. Psych.

    Dan ZdzieborskiDr. Zdzieborski's training and experience is in the area of child and adolescent clinical and forensic psychology. His recent professional experiences include positions with the Better Behaviours Service and Adolescent Forensic Service at the Centre for Addiction and Mental Health (CAMH) in Toronto. He has also held positions at Lutherwood Children's Mental Health Services, Hamilton-Wentworth District School Board, and Trellis Mental Health and Developmental Services. In addition to working in private practice, he currently holds a position at Kinark, Child and Family Services, and specifically, the Syl Apps Youth Centre, where he provides evidence-based psychological services to youth who have serious mental health difficulties and are also in conflict with the law. Dr. Zdzieborski has a particular interest in providing assessment and treatment services to children and youth who struggle with anxiety, depression, trauma-related, disruptive behaviour, and psychotic disorders. He offers CBT to address his client's individual needs, as well as Parent Management Training to support parents in managing their children's behaviour and mental health.

  • Rachel Wayne, Ph.D., C. Psych.

    Rachel Wayne, Ph.D., C. Psych.Dr. Wayne completed her Ph.D. in Clinical Psychology at Queen’s University. She has worked at the Rehabilitation Centre and Heart Institute at the Ottawa Hospital, Hotel Dieu Hospital in Kingston, Counseling and Disability Services at Queen’s University, and Baycrest Hospital. She provides assessment and treatment services for a range of mood and anxiety disorders, as well as for individuals with stress- or interpersonal-related difficulties. In addition to her work at the OCCT, Dr. Wayne also works at Toronto Western Hospital providing psychological services to individuals with work-related psychological trauma, musculoskeletal injuries, and/or chronic pain. She has a particular interest in working with hard-of-hearing individuals (including those with congenital or acquired hearing loss), as well as individuals with chronic health-related conditions or disabilities, including tinnitus.

  • Oksana Gravets, Psych.D., C. Psych.

    Oksana GravetsDr. Gravets recently held a staff position at St. Michael’s Hospital’s Department of Family and Community Medicine working with a variety of presenting difficulties. At the Operational Stress Injury Clinic, she provided treatments for traumatic stress injuries in veterans, serving members of the Canadian Forces and the police. More recently at the Toronto Western Hospital she was working with individuals experiencing work-related psychological trauma, physical injuries and chronic pain. Dr. Gravets also has experience practising in various healthcare settings in the U.K. including a family medicine health care team, a community child and adolescent mental health care service, an adolescent inpatient unit, a drug addictions service and a specialist inpatient and outpatient HIV clinic. Dr. Gravets provides CBT for a wide range of problems including depression, anxiety, anger, insomnia, chronic pain, bereavement, relationship difficulties, trauma, substance use disorders and chronic health problems. Her commitment lies with delivering evidence-based and outcome-oriented assessments and treatment plans which incorporate clients’ unique needs and goals.

  • Stephen Barker, Ph.D., C. Psych.

    Stephen BarkerDr. Barker has worked professionally with children and adolescents for over 40 years. He completed his doctoral training at the University of Toronto (OISE) and since then has worked in a variety of settings providing assessments, treatment and consultation. His work experience includes positions at a residential treatment centre for children and adolescents, a family court clinic, a hospital outpatient clinic, as a Senior Psychologist at the Peel Board of Education. In addition, he taught Educational Theory at York University and has provided in-service training sessions for many groups of professionals. Dr. Barker maintained a full-time practice for 15 years. In his work at the OCCT, he limits his practice to providing clinical and educational assessments. This is an area where he has a special interest and where he has developed a unique approach over the last 40 years. His assessments are concerned with not only understanding problems, but even more importantly to generating solutions and helping people to succeed.

  • Clarisa Markel, Ph.D., C. Psych.

    Clarisa Markel, Ph.D., C. Psych.Dr. Markel obtained a Ph.D. in School and Clinical Child Psychology at the Ontario Institute for Studies in Education (OISE) of the University of Toronto. She has held positions at Reach Out Centre for Kids (ROCK), Surrey Place Centre, the Toronto District School Board, and the OISE Counselling and Psychoeducational Clinic. For over 15 years Dr. Markel has been working with children and adolescents experiencing a variety of psychological concerns including ADHD, anxiety, defiance, depression, grief and bereavement, obsessive compulsive disorder (OCD), relationships issues, self-care, self-esteem, self-injury, sleep problems, stress, social-emotional challenges, and tics, among others difficulties. Dr. Markel also provides family therapy to support family members of all ages. She provides services in both English and Spanish.

  • Vicki Rombough, Ph.D., C. Psych.

    Vicki Rombough 240x240Dr. Rombough works with children, adolescents and young adults. In addition to her work at the OCCT, she provides psychological services and program supervision at the Integrated Services for Autism and Neurodevelopmental Disorders (ISAND) clinic in Toronto. Prior professional experiences include positions at North York General Hospital, The Hospital for Sick Children, Kinark Child and Family Services, Toronto District School Board, Holland Bloorview Kids Rehabilitation Hospital and York University. Dr. Rombough provides psychological and developmental assessments, as well psychological intervention and parent consultation/support. She has a special interest in providing CBT and mindfulness-based therapies to treat anxiety, depression, obsessive-compulsive disorder and behavioural challenges in children and adolescents. She is also dedicated to working with individuals with learning, attention or developmental differences, such as autism spectrum disorder (ASD), who also experience mental health concerns. In addition to her clinical work and research contributions, Dr. Rombough has provided training to other professionals, including ASD training to mental health clinicians across Ontario and globally through Sick Kids International.

  • Malak Abu Shakra, Ph.D., C. Psych.

    Malak Abu ShakraDr. Abu Shakra earned her Ph.D. from McGill University in Montreal and has held positions at the Jewish General Hospital’s Teenage Health Unit and Goldman Herzl Family Practice Centre, Montreal General Hospital’s Pain Clinic, and Royal Victoria Hospital’s Allan Memorial Institute. She works with adults and adolescents presenting with a wide range of psychological concerns (e.g., anxiety, depression, anger/violence, psychosis, personality disorders, autism spectrum, chronic pain, etc.). She has a particular interest in working with those at risk of alcohol and/or substance abuse and with teenagers who may be considered “difficult.” Dr. Abu Shakra is fluently trilingual and can provide services in English, Arabic and Hebrew.

  • Dora Zalai, M.D., Ph.D., C. Psych.

    Dora ZalaiDr. Zalai completed medical training in Hungary and worked as a physician prior to embarking upon a career as a psychologist. She has held positions at the University Health Network, London Health Sciences, St. Michael’s Hospital, St. Joseph’s Health Care (Hamilton) and a number of sleep clinics throughout Ontario. At the Oakville Centre for Cognitive Therapy, Dr. Zalai provides cognitive behavioural, mindfulness and acceptance-based treatments to older adolescents and adults who feel tired, overwhelmed, unhappy, anxious, or stuck in life. In addition, she provides cutting-edge sleep and body clock assessments and individually-tailored treatment interventions for sleeping difficulties. She can also incorporate sleep assessment and treatment into her work with individuals struggling with depression, anxiety, trauma, medical conditions, chronic pain and post-concussion symptoms. Dr. Zalai has educated clinicians and patient groups about the relationship between sleep, fatigue, mental and physical health in Canada, Europe, Asia and Africa and is passionate about developing cognitive behavioural therapy for insomnia programs in community and in hospital settings.

  • Melissa Mohan, Ph.D., C. Psych. (Supervised Practice)

    Melissa Mohan 240x240Dr. Mohan earned her doctoral degree at Western University. She has extensive training and experience in health and rehabilitation psychology, and while in London she worked at Victoria Hospital’s Behavioural Medicine Service, at University Hospital’s Epilepsy Program, and at St. Joseph’s Health Care’s Cardiac Rehabilitation and Secondary Prevention Program, as well as at its Rheumatology Day Program. Her training and experience in clinical psychology includes positions with the Mood and Anxiety Disorders Program, and the Assessment Program at London’s Regional Mental Health Care. In addition, she has worked at Western University’s Student Development Centre and in several private practices in the London area. At the OCCT, Dr. Mohan has a special interest in using CBT to help clients who are experiencing stress, anxiety, depression, relational issues, chronic pain, and a variety of other health challenges to optimize coping and to improve the quality of their lives.

  • Simerpreet Ahuja, Ph.D., C. Psych. (Supervised Practice)

    Simerpreet AhujaSimerpreet Ahuja completed her doctoral training in psychology at Thapar Institute of Engineering and Technology (TIET) in Patiala India in 2009. Prior to coming to Canada, she spent several years as an Assistant Professor of Psychology at TIET, teaching at both the undergraduate and graduate levels, while also maintaining an active program of research—she has published peer-reviewed papers in a number of well-regarded academic journals. In addition to her teaching and research work, Dr. Ahuja has many years of experience providing psychotherapy and counselling services. At the OCCT, Dr. Ahuja works with adolescents and adults experiencing a wide range of psychological concerns including depression, anxiety, anger, stress, low self-esteem and relationship problems. She has a special interest in providing vocational assessment services for individuals seeking guidance in career planning. Dr. Ahuja offers services in English, Hindi and Punjabi.

  • Leah Tobin, Ph.D. Candidate

    Leah TobinLeah Tobin completed her doctoral training in clinical psychology at the University of Calgary. Her work experience—obtained primarily in Calgary—includes positions at the Sheldon M. Chumir Health Centre’s Cognitive-Behavioural Therapy Service and its Regional Psychological Assessment Service, the Sunridge Medical Gallery’s Community Mental Health Clinic, the Foothills Medical Centre’s Mood Disorders Program and Addiction Centre, Alberta Health Services’ Forensic Adolescent Program, and the Peter Lougheed Centre’s Adult Psychiatric Inpatient Unit. At the OCCT, Leah provides CBT for adult and adolescent clients who are struggling with anxiety, obsessive-compulsive disorder (OCD), depression, stress, substance use and concurrent disorders. She has a special interest in helping individuals who are struggling with eating disorders and body image concerns.

  • Sarah Beresh, B.A.

    Sarah BereshA graduate of McMaster University's Honours English program, Ms. Beresh handles a range of administrative responsibilities at the Oakville Centre for Cognitive Therapy. Prior to joining the OCCT, she held a leadership position in a non-profit organization working alongside teenagers and young adults.

  • Tracey McIntosh

    Tracey McIntoshMs. McIntosh joined the OCCT in 2018, bringing with her many years of administrative and banking experience. She has also been involved in coaching gymnastics to young children, assisting with a kindergarten readiness program, and volunteering as a group facilitator at a grief and bereavement support centre for children and families. As part of the OCCT’s administrative team, Tracey liaises with patients and referral partners, assists with scheduling, and manages a range of business-related matters.