A study in the strategy for motor control of human masticatory system - about the participation of anticipation -

Research Project

Project/Area Number	12671893
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	補綴理工系歯学
Research Institution	Nagasaki University
Principal Investigator	NOGUCHI Kazuko Nagasaki University, School of Dentistry, Instructor, 歯学部, 助手 (50172771)
Co-Investigator(Kenkyū-buntansha)	YOSHIMATSU Tadashi Nagasaki University, School of Dentistry, Instructor, 歯学部, 助手 (50230800) YAMABE Yoshihisa Nagasaki University, School of Dentistry, Associate Professor, 歯学部, 助教授 (90191379)
Project Period (FY)	2000 – 2001
Project Status	Completed (Fiscal Year 2001)
Budget Amount *help	¥2,300,000 (Direct Cost: ¥2,300,000) Fiscal Year 2001: ¥600,000 (Direct Cost: ¥600,000) Fiscal Year 2000: ¥1,700,000 (Direct Cost: ¥1,700,000)
Keywords	jaw tapping / acoustic command signal / anticipation / surplus tapping / elderly adults / young adults / dual-task / motor control / 高齢有歯顎者 / 青年有歯顎者 / 高齢総義歯装着者 / ランダム周期 / 誤試行
Research Abstract	Five elderly dentulous people (mean age 72), three elderly edentulous people with dentures (65), nine dentulous young adults (25), nine dentulous young adults instructed dual-task (24), performed jaw-tapping movements in time to an acoustic signal train with random intervals, that 1.3 Hz interval appears the most frequently. The dual-task group was instructed to memorize words on the monitor screen while performing jaw tapping. We observed some parameters among Masseteric muscle EMG (Mm), Mandibular Kinegiogram, and acoustic signal on surplus tappings. 1. Incidences of surplus tapping in the dual-task group have no relation to numbers of 1.3 Hz repetition and were very low after intervals of 1.3 Hz x 2. Gape in dual-task group is small. 2. The surplus tapping after the interval of 1.3 Hz x 2 appear at intervals of 1.3 Hz from the preceding signal, and began to appear after some 1.3 Hz x 2 intervals. 3. The time lags between the expected signal at intervals of 1.3 HZ from the preceding signal and Mm burst onset of the surplus taping: Those average is smaller at the surplus tapping after 1.3 Hz intervals. (We guess that onset of Mm burst is before the confirmation of signal.) Those average is larger at the surplus tapping after 1.3 Hz x 2 intervals. (We guess that Mm burst onset in both elderly group begin after confirmation of signal.) 4. The more numbers of 1.3 HZ repetition is, the larger gape is except dual-task group. 5. The elderly group have more complete surplus tapping and the young group more incomplete surplus tapping. 6. It can be summarized as follows: In the dual-task group, the second task is not a distracted attention task but an arousal task. Subjects remember intervals that appear the most frequently, the surplus tapping appear at those intervals. And these show the degree of dependence on anticipation.