Chapter 57: Speech, Language, and Swallowing Disorders

INTRODUCTION

Disorders of communication and swallowing occur across the lifespan and may result from disruption of neurologic function and anatomical abnormalities of the head, neck, and respiratory system. Effective assessment and treatment involves collaboration across medical and rehabilitation disciplines. A discussion of normal function, incidence and prevalence, etiology, categories of impairment and treatment options is provided for each group of disorders.

COMMUNICATION DISORDERS

Introduction

Speech refers to motor acts that result in the production of sounds through the coordination of respiration, phonation, resonance, articulation, and prosody. Language is the symbolic organization of sounds into purposeful words and sentences to represent thought and includes linguistic elements such as morphology and syntax and paralinguistic elements of prosody.¹ Cognition refers to mental processes and systems, such as attention, perception, memory, organization, and executive function.²

Successful communication requires intact neural pathways and peripheral structures to plan, modify, and process speech, language, and cognition. Neural activation patterns of communication and cognition are widespread and include structures and circuits of the cerebrum, the brainstem, the limbic system, and the cerebellum (Table 57–1).

For example, in spoken language, humans require the temporal lobe for comprehension, the frontal lobe for production, the occipital lobe to visualize gestures and facial expression, and the parietal lobe for sensorimotor integration.³ The cerebellum and basal ganglia refine and coordinate speech movements, and the brainstem relays and receives the neural signals to and from the anatomy of speech and hearing^4,5 (Table 57–2).