Lingual Kinematics During Speech in Persons with Multiple Sclerosis

Abstract

Electromagnetic articulography (EMA) was used to examine lingual kinematicsin a heterogeneous group of seven adults with Multiple Sclerosis(MS), including two with relapsing-remitting and five with primary progressiveforms of MS, with the latter group including two participantswith dysarthria. Tongue tip and tongue body movements were tracked astwo sentences, one loaded with alveolar consonants and the other withvelar consonants, were read aloud six times each. The results are reportedas a series of descriptive case reports. Subclinical kinematic disturbanceswere identified in nondysarthric participants with MS. Specifically, theresults revealed that two MS participants (one dysarthric, one nondysarthric)exhibited significantly increased sentence durations compared tothe control group (n = 14). Two other MS participants (one dysarthric,one nondysarthric) exhibited significantly increased tongue movementspeed and distances, the effects of which may have counteracted to resultin comparable sentence durations to the control group. The remainingthree non-dysarthric participants with MS exhibited comparable values altothe control group for each kinematic parameter, with the exception ofincreased tongue back articulatory stiffness for one participant. The possiblemechanisms underlying the increased tongue movement duration,speed, and distance values are explored, including compensatory strategiesfor motor control disturbances.