耳鼻と臨床
Online ISSN : 2185-1034
Print ISSN : 0447-7227
ISSN-L : 0447-7227
32 巻, 6Supplement3 号
選択された号の論文の4件中1~4を表示しています
  • 松田 俊一
    1986 年 32 巻 6Supplement3 号 p. 1121-1135
    発行日: 1986/12/20
    公開日: 2013/05/10
    ジャーナル フリー
    The scalp topography of the auditory brainstem responses (ABRs) to monaural stimulation was studied in 28 normal young adults. The amplitudes and latencies of waves I through V were measured. On the basis of these data, the interpolated values were calculated by a computer and were displayed two dimensionally as a potential map. The results were shown as follows; 1) Wave I: The electrode ipsilateral to stimulation showed a low potential and the contralateral electrode showed a high potential to monaural stimulation. No left and right latency difference was noted. From the above, a dipole proceeding from ipsilateral to contralateral regions was hypothesized. 2) Wave II: High potentials areas appeared at the parietal occipital region on the ipsilateral side, but the latency was prolonged compared to the corresponding region. It is hypothesized that two dipoles exist at these regions. 3) Wave III: This wave was similar to the amplitude potential distribution of wave I with a high potential at the contralateral region. However, the ipsilateral latency was shorter than the contralateral latency. We hypothesize dipoles oriented both verticaly and horizontaly. 4) Wave IV: High potential areas were distributed widely over the vertex region. No difference between the contralateral and ipsilateral sides, and anterior and posterior regions were noted. However, the latency decreased at the ipsilatetral region and prolonged at the contralateral region. We hypothesize that two different dipoles of similar size proceeding in the vertical direction may exist. 5) Wave V: High potential regions were widely distributed at the contralateral region. The latency decreased at the contralateral region and prolonged markedly at the temporal regions with a difference of approx. 0.3msec. From the above, a large dipole proceeding in the vertical direction at the contralateral region and a small dipole are hypothesized. The statistics gathered from the normal subjects in this study will allow more accurate diagnosis of pathological conditions.
  • 江浦 陽一
    1986 年 32 巻 6Supplement3 号 p. 1136-1154
    発行日: 1986/12/20
    公開日: 2013/05/10
    ジャーナル フリー
    The purpose of present study was to investigate the developmental change of the waveforms, the amplitude and the latency of auditory brainstem responses (ABRs) in infants, in comparison with those in adults. Experiments were performed on 27 infants (1 month to 4 years of age) without major perinatal complication, and 7 adults with normal hearing. The topography of ABRs to monaural and binaural stimulation were obtained from 16 scalp electrode locations designated by the international 10-20 system with the reference electrode on the seventh cervical vertebra (CVII). A potential map of each ABR component and a time-course potential map were two-dimensionally displayed using a computer. The results were as follows: 1) There was a trend for all peak latencies to decrease with age. This effect was particularly pronounced for the later ABR components. The latency of wave I reached that of the adults at 2 months of age, wave III, wave V and interpeak-latencies at 2 years of age. 2) The ABR waveforms obtained from the infants above 2 years of age were similar to those of the adults. The wave II and wave III components in infants under 1 year of age had a tendancy to fuse. A peculiar finding in infant ABRs was that a peak appeared between wave I and wave II, which was named wave Ix. The wave was evident in infants less than 6 months of age, and disappeared at more than 2 years of age. Its origin was assumed to be at the central site of the eighth cranial nerve since the potential map of the wave was similar to that of wave I. 3) The two-dimensional map patterns of each component in infant ABRs were similar to those of adults. This fact suggests that the origin of ABR and the orientation of physiological firing in infants are identical with those in adults.
  • 白石 君男, 曽田 豊二, 加藤 寿彦, 松田 俊一, 江浦 陽一, 木村 謙一
    1986 年 32 巻 6Supplement3 号 p. 1155-1161
    発行日: 1986/12/20
    公開日: 2013/05/10
    ジャーナル フリー
    Auditory brainstem responses (ABRs) were simultaneously recorded from the vertex with reference electrodes placed on the ipsilateral earlobe (same side as stimulation), the chin, the seventh cervical vertebra (CVII) and the wrist. 14 adults with normal hearing were tested. The amplitudes and latencies of ABRs obtained by each electrode configuration were measured. The results led us to conclude: 1)A use of vertex and ipsilateral earlobe reference might prove useful for neurological assessment because the amplitudes of waves I and III were larger than in other configuration. 2) The largest wave V amplitude was recorded by the vertex and CVII configuration. This configuration may thus be used advantageously for audiological assessment of bone-conducted ABRs, since electrical artifact caused by a bone vibrator placed on the mastoid can be reduced. 3)A configuration using a reference electrode on the CVII or the chin is suitable for studying the potential distribution of ABRs over the scalp, because the potential of each ABR component propagated to the reference electrode positions was small.
  • 曽田 豊二, 白石 君男, 加藤 寿彦, 松田 俊一, 江浦 陽一, 井上 朝登
    1986 年 32 巻 6Supplement3 号 p. 1162-1170
    発行日: 1986/12/20
    公開日: 2013/05/10
    ジャーナル フリー
    The distributions of amplitudes and latencies of the auditory brainstem responses (ABRs) were studied in 6 normal adult subjects, with 15 electrodes being placed on the mid-coronal scalp region and 8 electrodes on the mid-sagittal scalp region in each subject. Wave I appeared as a negative deflection at the ipsilateral mastoid to a monaural stimulus and as a positive deflection at the vertex. The polarity inversion was accounted for by the “near-field” nature of the recording. The amplitudes of waves II to V were somewhat varied with different electrode locations over the scalp. A gradual prolongation of latencies of waves II, III and V were seen at the ipsilateral mastoid. The latency shifts may be caused by the spatial and temporal summations of several neural generators. As the spatial amplitude differences between adjacent electrode sites were not large, two-dimensional maps obtained by the interpolation method may be considered to accurately represent the distribution of these potentials over the scalp.
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