Joseph Duffy, PhD, is currently a Professor of Speech Pathology and a practicing Medical Speech Pathologist at The Mayo Clinic. His research interests include neurologic motor speech disorders (the dysarthrias and apraxia of speech), acquired language disorders (aphasia) and acquired psychogenic speech disturbances.
The primary focus of his research has been on defining the distinguishing clinical characteristics of these neurologic disorders, establishing their neurologic correlates and refining their differential diagnosis.
Functional speech disorders (FSDs; previously known as psychogenic speech disorders) encompass a wide variety of speech abnormalities with an unclear etiology. FSDs are not unusual… read more
Progressive apraxia of speech (PAOS) is a speech disorder resulting from an inability to send commands necessary to direct movements for normal speech due to… read more