Tongue and Jaw Movements in "Iowa" between Speakers with and without Dysarthria Secondary to ALS

Open Access
Costa, Samantha Nichole
Area of Honors:
Communication Sciences and Disorders
Bachelor of Science
Document Type:
Thesis Supervisors:
  • Ji Min Lee, Thesis Supervisor
  • Dr. Ingrid Maria Blood, Honors Advisor
  • dysarthria
  • ALS
  • tongue
  • jaw
  • kinematics
  • amyotrophic lateral sclerosis (ALS)
Purpose: Dysarthria is a type of motor speech disorder secondary to various neurological conditions including amyotrophic lateral sclerosis (ALS). The purpose of the current study is to identify 1) articulatory kinematic correlates of severity of dysarthria measured by speech intelligibility and speaking rate and 2) articulatory kinematic characteristics of the tongue and jaw in individuals with ALS. Methodology: Temporal and spatial articulatory kinematic data were collected using electromagnetic articulography from 21 individuals with dysarthria secondary to ALS and 20 healthy-aging individuals. The speech intelligibility data included the results of 139 listeners. Selected kinematic variables were examined in two ways: first, the correlation between the kinematic variables and speech intelligibility/speaking rate and second, the comparison of articulatory kinematic variables across groups (speakers with severe dysarthria secondary to ALS, speakers with mild dysarthria secondary to ALS, and healthy-aging speakers). Results: Temporal measures for tongue body and jaw such as duration and speed were significantly correlated with speech intelligibility and speaking rate. Speakers with higher intelligibility and faster speaking rate had greater tongue movements in the inferior-superior dimension. Across groups, speakers with severe dysarthria secondary to ALS had smaller convex hull areas, which represents articulatory working space, than speakers with mild dysarthria secondary to ALS. Discussion: During target word production, in addition to temporal measures, tongue body movement in the inferior-superior dimension and convex hull area may be valuable indicators of disease progression in ALS.