What Have We Learned From Physiological Approaches to Characterizing Dysarthria and Other Speech Production Disorders?

Abstract

Traditionally, speech-language pathologists (SLP) have been trained to develop interventions based on a select number of perceptual characteristics of speech without or through minimal use of objective instrumental and physiologic assessment measures of the underlying articulatory subsystems. While indirect physiological assumptions can be made from perceptual assessment measures, the validity and reliability of those assumptions are tenuous at best. Considering that neurological damage will result in various degrees of aberrant speech physiology, the need for physiologic assessments appears highly warranted. In this context, do existing physiological measures found in the research literature have sufficient diagnostic resolution to provide distinct and differential data within and between etiological classifications of speech disorders and versus healthy controls? The goals of this paper are (a) to describe various physiological and movement-related techniques available to objectively study various dysarthrias and speech production disorders and (b) to develop an appreciation for the need for increased systematic research to better define physiologic features of dysarthria and speech production disorders and their relation to know perceptual characteristics.