1976 年 79 巻 5 号 p. 591-598
A preliminary investigation was made for establishing an automatic method of scoring of brain stem response.(BSR).Averaged BSR to click stimuli was recorded in 7 normal young children and 4 normal adults.They were scored visually and by 3 different methods of amplitude measurement.
The stimuli were given to the subject through a loudspeaker at intensity levels of 10, 20, 30 and 40 dB above mean subjective thresholds of normal adults(HL) for young children and of 0, 10, 20 and 30 dB(HL) for adul subjects.Ten averaged responses were recorded with each stimulus intensity and additional 10 traces were made without stimulation.Thus 50 traces were obtained per subject.
The amplitudes of the responses of all traces were measured using 3 different methods shown in Fig.i(A, B.C).Then 5 percent rejection limits were calculated of the amplitudes of 10 control traces measured by the 3 methods.These values were used as amplitude criteria for judging the presence or absence of a response.Responses whose amplitude exceeded the above-mentioned criteria were scored positive, and the rate of positive responses in the 3 methods were compared with that in the visual scoring.
Results obtaiaed were as follows:
1) In young child group, Method B and C achieved almost similar detectability of the response as did visual scoring, whereas the rate of positive responses in Method A was significantly lower than those in B and C.
2) In adult groug, on the contrary, no such a significant difference was found in the response detectability-among the 3 methods, though all of the methods showed 15 to 40 percent lower delectability than that of visual scoring.
3) We thus concluded that Method B was regarded as the most useful procedure for measuring response amplitude automatically