Our Clinicians

Keri Height, PsyD


keri-120Dr. Height is a clinical psychologist and Assistant Professor at The Geisel School of Medicine at Dartmouth. she is licensed in both New Hampshire and Vermont and is also certified to provide tele-therapy through the PSYPACT, which allows her to accept clients from 17 additional states. She received her doctorate degree from University of Hartford and completed an APA accredited pre-doctoral internship and post-doctoral fellowship at Yale University School of Medicine. Prior to moving to New Hampshire in 2014, she was an assistant professor of psychiatry at Yale University and Clinical Director of the Yale Stress Center, a cutting edge interdisciplinary clinical and research center specializing in interventions for stress and addictive behaviors.

Dr. Height believes in the interconnectedness of the mind and the body and that treatment should be geared toward helping the whole person improve health and wellbeing. Dr. Height specializes in working with adolescents and adults who are having difficulty coping with stress,  experiencing symptoms of anxiety, interpersonal conflict, low mood, concentration and attention problems, emotional dysregulation, eating disorders, body dysmorphia, substance use difficulties, personality disorders and sleep problems. She has expertise in working with individuals experiencing medical symptoms or conditions that may be exacerbated by stress, including tension headaches and migraines, chronic pain, gastrointestinal distress, hypertension, overeating and substance misuse.   She especially enjoys working with young people who have experienced a first episode of psychosis.  Dr. Height has extensive experience working with individuals with chronic mental illness, as well as adolescents and adults with developmental disabilities.  She is trained in Family Based Therapy for Anorexia, Dialectical Behavioral Therapy, Cognitive Behavioral Therapy, Acceptance and Commitment Therapy, Biofeedback, various treatment modalities for addictions, and Mindfulness Based Stress Reduction (MBSR).  She also is available for fitness for duty evaluations, Autism Spectrum Disorder evaluations, comprehensive psychological evaluations and forensic assessments.

Regan Stanger, MD

Medical Director

Dr. Regan R. Stanger is a child, adolescent, and adult psychiatrist with extensive experience in both psychopharmacology as well as cognitive behavioral therapy and psychodynamic psychotherapy. A Diplomate of the American Board of Psychiatry and Neurology, Dr. Stanger holds two board certifications in Adult Psychiatry and Child & Adolescent Psychiatry. She joined Hanover Psychiatry after working in private practice on the Upper East Side of Manhattan for twelve years.

Dr. Stanger graduated from Dartmouth College in 1993 and attended medical school in New Jersey.  She completed her intern year of residency at the Yale-New Haven Hospital in Internal Medicine. She then joined the Department of Psychiatry at NewYork-Presbyterian Hospital, Weill Cornell Medical Center in New York City for her residency in Adult Psychiatry and her fellowship in Child & Adolescent Psychiatry. Following her fellowship, she entered private practice in New York City. During this time, she completed four years of additional psychoanalytic training at the New York Psychoanalytic Institute and taught psychiatry residents while on the voluntary faculty at NewYork-Presbyterian Hospital. She also served on the advisory board of the David Nee foundation, which works to prevent suicide in young adults. Currently, she is acting as the faculty advisor to the Student Needs and Assistance Program (SNAP) at the Geisel School of Medicine at Dartmouth and is a supervisor for Psychiatry residents at the Dartmouth-Hitchcock Medical Center.

Dr. Stanger focuses on working with children, adolescents, and young adults. She is an expert in psychopharmacology and in utilizing different modalities of psychotherapy to treat patients for attention deficit disorder, learning disabilities, language based disorders, autism spectrum disorders, impulse control disorders, mood disorders, anxiety disorders, and eating disorders. She also sees patients who may not meet criteria for a psychiatric diagnosis but are seeking support with peer/ romantic/ family relationships, academics, issues with gender and sexuality, transitions to college, or career issues.

Dr. Stanger utilizes play therapy with younger children to help them express their emotions through play, which can lead to changes in behavior. She uses cognitive behavioral therapy to help patients understand how their thoughts influence their emotions, and how to learn coping skills. Dr. Stanger also finds psychodynamic principles to be very helpful in understanding how past relationships and experiences affect a patient’s current thoughts and emotions.

As part of her work with children, Dr. Stanger also collaborates closely with parents. She works with families to provide parenting advice and to address issues including adoption, divorce, and illness/death of a family member. She involves people in a patient’s life including other mental health professionals, pediatricians, internists, schools, educational consultants, and tutors. She understands that patients are tremendously influenced by their family and community relationships, and she works to educate and counsel these important members of a patient’s life as part of a holistic treatment plan.

Maurissa Abecassis, PhD

Dr. Abecassis is a licensed clinical psychologist and assistant professor in the Geisel School of Medicine at Dartmouth with specialized training in Neuropsychology. Dr. Abecassis offers a wide range of assessment services for across the lifespan from late adolescence to older adulthood. Initially trained as a developmental psychologist, Dr. Abecassis brings a unique developmental/lifespan perspective to her practice. She offers a range of clinical services including Neuropsychological and Psychoeducational assessment services. She is able to offer comprehensive Neuropsychological evaluations and recommendations for clients with neurological concerns such as Epilepsy, Multiple Sclerosis, concussions, movement disorders or with concern about possible degenerative conditions such as dementias. She is also experienced in caring for patients with complex medical (genetic conditions, diabetes, post-cancer treatment) and psychiatric histories (depression, anxiety, PTSD, bipolar disorder) that can affect thinking, memory, reasoning, language skills or day to day functioning. Evaluations also offer clients and families a range of recommendations to further their wellness needs. She also has experience providing psychological evaluations for pain pump and spinal stimulator candidates and collaborates on some Fitness for Duty evaluations, as well.

She also has extensive experience working with and serving the needs of college aged and young adult clients requiring psychoeducational-neuropsychological evaluations due to academic difficulties, mood difficulties or related diagnoses such as ADHD. She also offers interventions for neuropsychological/executive functioning difficulties such as cognitive behavioral treatment for ADHD and cognitive remediation for older adults.

Dr. Abecassis is delighted to return to Hanover Psychiatry, where she completed her postdoctoral fellowship, to serve the assessment and intervention needs of clients in this region. She returns to us from a faculty appointment as a neuropsychologist in the department of Neurology at the Indiana University School of Medicine.

Sarah Craig (Bujarski), PhD

Dr. Craig works primarily with adults and is experienced in treating a variety of concerns, including: trauma/PTSD, general anxiety, social phobia, panic attacks, sleep problems, chronic pain, depression, and Bipolar Disorder.  Dr. Craig’s interest in anxiety and mood disorders also extends to women during the perinatal period (both during pregnancy and in the postpartum period). She is currently undergoing a rigorous training endeavor to be certified by Postpartum Support International (PSI) as a specialist in maternal mental health treatment. This training is internationally recognized and evidence-based.

Dr. Craig’s specialty is in working with clients who may have more than one mental health diagnosis. When working with such clients, she strongly believes in the value of a collaborative working relationship with each client, striving to develop treatment approaches unique to each individual. She understands that seeking treatment can be difficult, and she aims to create a safe, understanding environment in which she can help clients identify and reach their personal mental health goals.

Dr. Craig uses state-of-the art science to inform her clinical work. She actively researches anxiety and substance misuse and has received National Institute on Alcohol Abuse and Alcoholism (NIAAA) grant funding for her work. She has dedicated her early career to understanding and improving psychotherapy treatments to ensure people receive the best, most efficient treatment available.

Matthew Duncan, MD

Matthew Duncan, MD, is an honors graduate of the Geisel School of Medicine, did his internship at Brown University, and completed his psychiatry training at the Harvard Longwood Psychiatry Residency Training Program in Boston. Since training, he has worked as Acting Director of Psychiatry at the Indian Health Service in Fort Defiance, Arizona and in private practice in a group setting with primary care and specialty physicians in his home state of Utah. He has moved back East to join the Psychiatry Department faculty where he provides clinical care and teaching, including leading the medical student teaching for the Department. At Hanover Psychiatry he serves as a diagnostician and psychopharmacologist.


Ron Green, MD

Ron Green, M.D. is a board-certified psychiatrist and an expert in pharmacotherapy, psychotherapy and neuropsychiatry. He is a Professor of Psychiatry, Active Emeritus, at The Geisel School of Medicine at Dartmouth and a longtime member of its faculty.

Dr. Green is a graduate of the University of Vermont College of Medicine, did his residency in psychiatry at Dartmouth then served as a psychiatrist in the U.S. Navy for two years. He has been at Dartmouth since then, first for 13 years, as Director of the Psychiatry Consultation/ Liaison Service at the VA Medical Center in White River Junction, Vermont, following which, for 25 years, he was the Residency Program Director in Psychiatry at Dartmouth-Hitchcock Medical Center. Since 2009 he has been a staff psychiatrist at Hanover Psychiatry.

In Ron’s long career, he has authored many scholarly works and his professional reach has gone far beyond the environs of Dartmouth. One example is his text, co-authored with Dr. Robyn Ostrander, and published in 2009 by WW Norton, “Neuroanatomy for Students of Behavioral Disorders”. As well he has garnered many local, regional and national teaching awards, including the 2013 American Psychiatric Association’s annual “Irma Bland Excellence in Residency Teaching Award” and the New Hampshire Psychiatric Society’s 2016 Leadership Award in the Service of the Mentally Ill. On the light side, Dr. Green for six years was medical consultant to HBO’s “The Sopranos”. He prescribed Tony Soprano’s medication (for the show’s script and not for Mr. Gandolfini of course) and helped design psychotherapy scenes between Mr. Soprano and Dr. Melfi.

Dr. Green is known as a doctor’s doctor. His stature, experience and guidance graces not just Hanover Psychiatry but the entire department of psychiatry at Dartmouth.

Caroline Shackett, PhD, NCSP

Dr. Shackett is a licensed psychologist in New Hampshire, Vermont and New York. She is also a nationally certified school psychologist. She completed her doctoral graduate training at the University of Massachusetts – Amherst and postdoctoral fellowship training at the Rural Vermont Consortium of the Precision Valley in Springfield, VT. Dr. Shackett sprovide individual therapy and diagnostic assessment services for children and adolescents. She has extensive background in positive behavioral support and interventions and is able to provide parenting supports. Dr. Shackett provides psychological, psychoeducational, and autism evaluations, in addition to functional behavior assessments. She has worked in and consulted with schools on a variety of topics ranging from assessments to interventions and supports. Her research background involves interventions promoting academic achievement and behavioral supports. Dr. Shackett takes an ecological, collaborative approach to working with clients and their families that involves behavioral and cognitive behavioral methods.

Gillian Sowden, MD

Gillian Sowden, MD, is a licensed psychiatrist and Assistant Professor of Psychiatry at The Geisel School of Medicine at Dartmouth.  Dr. Sowden’s clinical interests include adult psychopharmacology for mood, anxiety, personality, eating and trauma related disorders, substance abuse and women’s mental health.  She also has expertise in providing psychodynamic therapy.

Dr. Sowden has special interest in medical student education and previously taught medical students at Harvard Medical School.  Currently she is supervising and teaching psychiatry residents at Dartmouth-Hitchcock Medical Center. Research interests have included collaborative care for patients with depression and heart disease, and simulation training for psychiatry residents.

Dr. Sowden graduated from Williams College, summa cum laude, with a BA in Biology & Biochemistry.  She graduated magna cum laude from the Harvard Medical School and did her residency in Adult Psychiatry at Cambridge Health Alliance, a Harvard Medical School affiliate.

Christopher Spofford, PhD

Dr. Spofford is a licensed clinical psychologist in the states of New Hampshire and Rhode Island and Assistant Professor of Psychiatry at The Geisel School of Medicine at Dartmouth.  He completed his doctoral graduate training at the University of Massachusetts – Amherst and his postdoctoral fellowship training at the Alpert Medical School of Brown University.  Dr. Spofford’s clinical and research focus has been on the application of cognitive-behavioral interventions (CBT) to treat anxiety-related disorders and depression.  Dr. Spofford has extensive experience in the treatment and evaluation of obsessive-compulsive disorder (OCD) and OC related disorders, having completed a Brown University postdoctoral fellowship in this area.  From 2012- 2016, Dr. Spofford served as a research psychologist at the Providence VA Medical Center where he coordinated multiple projects investigating the treatment and diagnosis of combat-related PTSD.  Dr. Spofford joined the Hanover Psychiatry team in September of 2016.   He is available to provide individual therapy and diagnostic assessment services for adults and adolescents in both our Hanover and Concord offices.

Benjamin Swerdlow, MA

Benjamin Swerdlow (he/him) is a psychology intern in the final stage of his doctoral training at Hanover Psychiatry. Benjamin received his Masters degree in clinical psychology and completed his doctoral academic training at the University of California, Berkeley. He has experience providing evidence-based psychotherapy services in community clinics and hospitals, including the Berkeley Psychology Clinic and Kaiser Permanente.

Benjamin works primarily with adults who experience a range of concerns, including depression, anxiety, gender and sexual identity development, interpersonal challenges and relationship concerns, emotion regulation, bipolar disorder, and borderline personality disorder. He employs a collaborative, integrative approach that is grounded in Cognitive Behavioral Therapy, and incorporates elements of Dialectical Behavioral Therapy, Acceptance and Commitment Therapy, and Mindfulness-Based Stress Reduction. This integrative approach is designed to tailor state-of-the-science therapies to each client’s unique life experiences and therapy goals.

In addition to individual therapy, Benjamin has a particular interest in working with couples, where he draws heavily on Collaborative Couple Therapy and Emotionally Focused Therapy for Couples. In all of his work, Benjamin strives to be authentic, culturally responsive, and LGBTQIA+-affirming.

Alongside his clinical practice, Benjamin is actively involved in research. His doctoral dissertation research examines how romantic couples respond to and regulate each other’s emotions in their daily lives. He has also been involved in conducting research on mood disorders, impulsivity, affect regulation, non-suicidal and suicidal self-injury, and interventions for emotionally impulsive aggression.

Rejini Thomas, MD

Dr Thomas is a Child, Adolescent, and young adult psychiatrist who is licensed in NH and recently joined the practice.  Dr Thomas’s clinical training primarily emphasizes on the treatment of children, adolescents, and young adults with diverse diagnoses including but not limited to ADHD, trauma related disorders, anxiety, mood disorders and psychotic spectrum illness.  Dr Thomas is a graduate of Malankara Orthodox Syrian Church Medical College, Kerala, India and completed her psychiatry residency at Maimonides Medical Center, Brooklyn, NY. Following residency Dr Thomas pursued 2 years of training in Child and Adolescent psychiatry at Dartmouth Hitchcock Medical Center. During residency and fellowship she also received training in psychotherapy modalities such as Cognitive Behavioral therapy and different behavioral models of Parent Management Training.  Dr Thomas is passionate about working with children, adolescents, and young adults, believes in having a holistic approach in treatment and understands the importance of multiple prong approach in management of disorders by including the therapy and academic supports to psycho pharmacology whenever necessary.

Lauren Vazquez, MS

Lauren Vazquez, M.S., is a psychology intern completing her final year of doctoral training in child clinical psychology. She received her undergraduate degree from Pomona College and completed her doctoral requirements at the Pennsylvania State University. She has experience providing evidence-based assessment and psychotherapy services in childcare centers, schools, and community mental health settings through training programs at the Pennsylvania State University Child and Adolescent Outpatient Clinic, the Pennsylvania State University Anxiety Clinic and the State College Area School District.

Lauren works primarily with children and adolescents who experience a range of presenting problems, including anxiety, depression, obsessive/compulsive behaviors, sleep, social skills, attention- and learning-related difficulties, and disruptive behaviors. She strives to deliver evidence-based and developmentally informed practices to meet the goals of clients and their families.

Lauren is strongly committed to translational research focused on utilizing the unique strengths of children and their families to improve intervention and prevention practices. Her current research activities involve investigating the development of emotion regulation strategies in early childhood, with particular interest in how parents can support their child’s healthy development. For her dissertation, she examined young children’s neural processing of caregivers’ emotional voices, particularly how caregivers’ expression of emotion at home informs children’s neurophysiological development.