Rose, Darrell E.||Williams, J. David
M.A. (Master of Arts)
Department of Speech
This study was undertaken to investigate the mastoid and forehead as positions for the placement of the bone conduction oscillator when testing mentally retarded children and children with normal intelligence. Specifically, the two oscillator positions were investigated on each of the two populations to explore the following: What is the variability of the two placements for each group? What is the difference in dB between the two placements across the test frequencies for each group? What variability and differences in thresholds for the two placements exists across frequencies between the mentally retarded children and children with normal intelligence? For the purpose of this investigation, mentally retarded children are defined as children with an intelligence quotient between 50 and 65 as scored on a standardized intelligence test (Stanford-Binet L-M, and/or WISC). Children with normal intelligence are defined as children with an intelligence quotient between 122 and 155 as scored on a standard intelligence teat (California Test of Mental Maturity). Method Relative bone conduction thresholds were obtained at three test sessions from the mastoid and forehead process of 10 mentally retarded children and 10 children with normal intelligence. In all the sessions the contralateral ear was masked. The subjects were devoid of ear pathology. Results Thresholds obtained from the forehead have a poorer threshold than do the thresholds obtained from the mastoid. This is true for Group A (children with normal intelligence) and Group B (mentally retarded children). In terms of the variability of the differences between thresholds, Group A demonstrates less variability in the differences between thresholds for 250, and 1000 Hz. Group B demonstrates less variability in the differences between thresholds for 500, 2000, and 4000 Hz. At 1000 there is a significant discrepancy between groups for the mean threshold differences between placements (P> .05). At 250, 500, 2000 Hz, and 4000 Hz there is no significant discrepancy between groups for the mean threshold differences between placements (P<.05). At all test frequencies there was no group by tests interaction. In terms of the variability of the thresholds. Group A demonstrated the smallest amount of variability at the mastoid placement and Group B demonstrated the smallest amount of variability at the forehead placement.
Barber, Prudence S., "Oscillator placement in bone conduction testing with selected groups of children" (1967). Graduate Research Theses & Dissertations. 4229.
xi, 69 pages
Northern Illinois University
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