WHOLE-HEAD MAPPING OF MIDDLE-LATENCY AUDITORY-EVOKED MAGNETIC-FIELDS
WHOLE-HEAD MAPPING OF MIDDLE-LATENCY AUDITORY-EVOKED MAGNETIC-FIELDS
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DOI：
10.1016/0168-5597(94)90018-3
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发表时间：
1994-09-01
期刊：
影响因子：
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通讯作者：
MCEVOY, L
中科院分区：
文献类型：
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作者：
MAKELA, JP;HAMALAINEN, M;MCEVOY, L
我们用122通道全头SQUID梯度仪记录了9名健康受试者的中潜伏期听觉诱发磁场。刺激为三联声，总持续时间为2.5 msec，每333 msec交替传递一次到两耳。在研究的18个脑半球中，对侧点击在16个脑半球引发P30m反应，在12个脑半球引发P50m反应；同侧的咔哒声分别在7个半球和13个半球发生。磁场模式令人满意地解释了电流偶极子在16和4半球的对侧和同侧P30m，在4和10半球的对侧和同侧P50m。P30m和P50m的峰值潜伏期不受刺激侧影响。结果表明，中潜伏期听觉诱发反应受到听觉皮层结构的强烈影响，从MLAEF潜伏期评估的皮层听觉区域输入潜伏期的差异并不能解释对侧和同侧刺激的晚期听觉诱发场的潜伏期差异。
We recorded middle-latency auditory evoked magnetic fields from 9 healthy subjects with a 122-channel whole-head SQUID gradiometer. The stimuli were click triplets, 2.5 msec in total duration, delivered alternately to the two ears once every 333 msec. Contralateral clicks elicited P30m responses in 16 and P50m responses in 12 out of 18 hemispheres studied; ipsilateral clicks did so in 7 and 13 hemispheres, respectively. The field patterns were satisfactorily explained by current dipoles in 16 and 4 hemispheres for contra- and ipsilateral P30m, and in 4 and 10 hemispheres for contra- and ipsilateral P50m. The peak latencies of P30m and P50m were not affected by stimulation side. The results show that middle-latency auditory evoked responses receive a strong contribution from auditory cortical structures, and that differences of input latency to cortical auditory areas, evaluated from MLAEF latencies, do not explain the latency differences seen in late auditory evoked fields to contralateral vs. ipsilateral stimulation.