Our Clinicians

Keri Height, PsyD


keri-120Dr. Height is a clinical psychologist, licensed both in New Hampshire and Vermont, and Assistant Professor at The Geisel School of Medicine at Dartmouth. 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.

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, 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 is available to provide Biofeedback for many of these conditions.  Furthermore, 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, 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.

Carolyn Solzhenitsyn, MD

Medical Director

Carolyn Solzhenitsyn, MD is the Medical Director at Hanover Psychiatry. A faculty member at The Geisel School of Medicine at Dartmouth, she specializes in psychopharmacology and in Cognitive Behavior Therapy.

Dr. Solzhenitsyn is a graduate of the University of Pennsylvania School of Medicine, and completed her psychiatry residency at the Hospital of the University of Pennsylvania. While at Penn, she received her training in Cognitive Behavior Therapy from Aaron T. Beck, MD (the founder of Cognitive Therapy) and Judith S. Beck, PhD.

Prior to joining Hanover Psychiatry, Dr. Solzhenitsyn had a private practice in New York City.  She currently sees people for psychopharmacology and Cognitive Behavioral Therapy in both our Hanover and Concord offices.

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.

Burl Daviss, MD

Burl Daviss, MD, is an Associate Professor of Psychiatry and Interim Section Chief of Child and Adolescent Psychiatry at the Geisel School of Medicine.  Dr. Daviss is a child and adolescent psychiatrist who specializes in the pharmacological treatment of ADHD and mood disorders in youth and young adults. He is the former medical director of the Center for Children and Families at the University of Pittsburgh, and he is a member of the American Academy of Child and Adolescent Psychiatry. Dr. Daviss has been referenced in several journals including the Journal of the American Academy of Child and Adolescent Psychiatry and the Journal of Child and Adolescent Psychopharmacology. He has also received a career development award from the National Institute of Mental Health to develop research expertise in the assessment and treatment of ADHD and comorbid mood disorders in youth.

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.

Karyn Gunnet Shoval, PhD

Karyn is an advanced Postdoctoral Clinical Fellow at Hanover Psychiatry.  Prior to coming to Hanover Psychiatry, she completed a 2.5 year Fellowship in the Psychology Department at Harvard University where she has conducted research on Langerian Mindfulness and Patient Labeling under the direction of Dr. Ellen Langer, Professor of Psychology.  Karyn continues to teach Intermediate Statistics and a Pro-seminar in Graduate studies at Harvard University.

Prior to finishing her Ph.D. in Counseling Psychology from Lehigh University, Karyn completed her APA-Accredited Internship in Clinical Psychology at Yale School of Medicine, where she received a Leadership Award for Outstanding Contributions to the Internship Program.  Her internship sites at Yale included the Yale Stress Center and Behavioral Medicine in the Department of Psychosomatic Medicine at Yale New Haven Hospital.  At the Stress Center she worked with individuals presenting with a wide range of psychological and psychosomatic difficulties.  At YNHH, she worked with liver transplant patients needing alcohol and weight counseling and was the primary and first full-time psychology fellow on the general hospital’s Psychiatric Consultation Liaison team.

Karyn was trained in a Scientist-Practitioner Generalist doctoral program that emphasized training multiculturally competent psychologists in all aspects of clinical and academic work.  She completed practicum/externship trainings in a wide variety of settings, including University of Pennsylvania’s Counseling and Psychological Services, Muhlenberg College’s Counseling Center, the Adolescent-HIV clinic in the Department of Adolescent Medicine at the Children’s Hospital of Philadelphia and the Yale Stress Center, where she worked under the clinical direction of Dr. Keri Height, prior to Dr. Height assuming the role of director of Hanover Psychiatry.

Karyn’s clinical training has primarily emphasized the treatment of adults and couples presenting with diverse concerns including, but not limited to, depression, anxiety, personality disorders, weight concerns and eating behaviors, emotion dysregulation, communication difficulties, work-life balance, PTSD, relationship issues (adult child-parent, intimate partner, etc.), alcohol concerns, and life stress related concerns.

Karyn has been trained in behavioral, mindfulness-based, cognitive behavioral, dialectical behavioral and psychodynamic treatments, as well as biofeedback.  She uses her general practitioner background to fit the right treatment approach(s) to the client, rather than the client to a particular treatment approach. Karyn is very excited to be a part of the clinical team at Hanover Psychiatry and has day time and evening appointments available.

Lucas S. LaFreniere, MS

Lucas (“Luc”) LaFreniere, M.S., is a psychotherapy intern undergoing the final stage of his doctoral training in clinical psychology.  Luc received his Master’s degree in clinical psychology and completed his doctoral training at the Pennsylvania State University. There, he provided individual and group psychotherapy for six years, while also co-supervising the education and training of beginning therapists. In addition, he served as an administrator in a specialized anxiety clinic, taught several Penn State undergraduate courses in clinical psychology, and conducted treatment research. He recently defended his doctoral dissertation, which tested a treatment he developed for helping clients savor enjoyable experiences. This new therapy successfully reduced worry, anxiety, and depression and increased positive emotions, optimism, and enjoying the present moment. Prior to his doctoral work, Luc graduated with a B.A. from the University of Michigan honors program as a James B. Angell scholar. During that time, he provided supervised counseling at an outpatient private practice clinic, served as a group therapy co-therapist, and counseled youth in a juvenile delinquency program on a historic sailing vessel.

Luc specializes in cognitive-behavioral treatments for adults with anxiety disorders. He also has broad experience in variety of other diagnoses and evidence-based therapies for adults. His approach emphasizes creating a supportive and warm relationship, teaching useful new skills, open collaboration between client and therapist, and client empowerment and encouragement. In his research, he has identified factors that prolong anxiety problems, then designed several treatments to weaken those factors. His work suggests that by embracing true present-moment joys, worriers can let go of unlikely future fears. Luc’s enthusiasm and love for therapy informs every area of his work.

Jeffrey Reed, DO

Dr. Jeffrey D. Reed is an adult psychiatrist with training in psychopharmacologic and psychotherapeutic interventions. Dr. Reed completed his general internship and residency in adult psychiatry and research at Dartmouth-Hitchcock Medical Center (DHMC) in Lebanon, NH. Dr. Reed focuses academically and is an expert on the diagnostic evaluation and pharmacologic management of psychotic disorders including schizophrenia, schizoaffective, schizophreniform and brief psychotic disorders. He is also extensively trained in the evaluation and treatment of psychosis in affective disorders such as bipolar and major depressive disorders. As a product of his work in the inpatient and office settings, he is experienced with the use and monitoring of mood stabilizers, antidepressants and oral and long-acting injectable antipsychotic medications. Dr. Reed is particularly passionate about the safety and efficacy of medication management including careful monitoring of individuals involved in long-term medication treatment. As part of his work, Dr. Reed is excited to work closely with families and other supports in accordance with patients’ request and permission.

Academically, Dr. Reed trained in the Research Track Program of the Department of Psychiatry at DHMC and The Geisel School of Medicine at Dartmouth working on a study investigating the effects of substance use on individuals living with schizophrenia. Dr. Reed is a former neuroimaging fellow for the Sibling Study of Schizophrenia conducted at the National Institute of Mental Health in Bethesda, MD and previously worked in the development and implementation of neuroimaging research studies at the Massachusetts General Hospital Martinos Center for Biomedical Imaging in Charlestown, MA.

Robert M. Roth, PhD, ABPP

Robert M. Roth, PhD is an Associate Professor of Psychiatry at The Geisel School of Medicine at Dartmouth and Director of Adult Neuropsychological Services at Dartmouth-Hitchcock Medical Center. Dr. Roth is Board Certified in Clinical Neuropsychology.  His pre-doctoral training in neuropsychology took place at the Montreal Neurological Institute and Yale University School of Medicine, and he completed post-doctoral training in neuropsychology and neuroimaging at the Geisel School of Medicine at Dartmouth.

Dr. Roth provides neuropsychological assessments for a wide variety of clientele ages 16 and older who are experiencing cognitive problems such as memory loss, word finding difficulty, inattention or distractibility, or executive dysfunction (e.g., impulsivity, disorganization, poor decision making or problems solving). The Adult ADHD Program team provides detailed psychological and neuropsychological assessments for adults with suspected or previously diagnosed ADHD. Dr. Roth is committed to understanding the person as a whole, considering cognitive, emotional, personality, social, and other factors that can impact on a client’s ability to function at their maximal potential.

Dr. Roth is also a neuroscientist conducting neuropsychological and brain imaging research into a number of disorders including ADHD, schizophrenia, OCD, and substance abuse. His research is especially concerned with the role of executive functions in the etiology and treatment of such conditions. He has authored over 70 peer-reviewed scientific publications, as well as being the co-author of two published instruments for the assessment of executive functions (The Behavior Rating Inventory of Executive Function – Adult version, and the Tasks of Executive Control).

Caroline Shackett, PhD

Dr. Shackett is a child and adolescent psychologist at Hanover Psychiatry and 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 has worked in and consulted with schools on a variety of topics ranging from psychoeducational assessments to positive behavioral interventions and supports. She provides individual therapy and diagnostic assessment services for children and adolescents. Dr. Shackett has training and expertise in functional behavior assessments and interventions. 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,

Regan Stanger, MD

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 recently joined Hanover Psychiatry after working in private practice on the Upper East Side of Manhattan for twelve years.

Dr. Stanger  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.

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.