Fiona Hill. Her primary practice is as a Clinical Neuropsychologist, also practicing as a Psychologist: Addiction (Substance Use Disorder), a Psychologist: Clinical, a Psychologist: Rehabilitation, a Psychologist, a Psychologist: Adult Development & Aging, a Psychologist: Forensic, a Psychologist: Mental Retardation & Developmental Disabilities, and a Psychologist: Group Psychotherapy.