Physiologic development of tongue-jaw coordination from childhood to adulthood.
OBJECTIVE
This investigation aimed to examine the development of tongue-jaw coordination during speech from childhood to adolescence.


METHODS
Electromagnetic articulography was used to track tongue and jaw motion in 48 children and adults (aged 6-38 years) during productions of /t/ and /k/ embedded in sentences.


RESULTS
The coordinative organization of the tongue and jaw exhibited changes until the age of 8-11 years and continued to undergo refinement into late adolescence. The tongue-tip and tongue-body were observed to develop unique kinematic relations with the jaw. While tongue-tip movement became increasingly synchronized with jaw movement, tongue-body and jaw retained movement independence but developed a more consistent kinematic relation.


CONCLUSIONS
The present results support the notion that speech motor development is nonuniform, with a refinement period from mid-childhood to late adolescence.
Cheng
Hei Yan
HY
The University of Queensland, Brisbane, Queensland 4072, Australia. y.cheng@shrs.uq.edu.au
Murdoch
Bruce E
BE
Goozée
Justine V
JV
Scott
Dion
D
D000293:Adolescent; D000328:Adult; D002648:Child; D055590:Electromagnetic Phenomena; D005260:Female; D006801:Humans; D008297:Male; D008334:Mandible / Q000254:growth & development / Q000502:physiology*; D009068:Movement / Q000502:physiology; D014059:Tongue / Q000254:growth & development / Q000502:physiology*