INTRACEREBRAL POTENTIALS TO RARE TARGET AND DISTRACTER AUDITORY AND VISUAL-STIMULI .3. FRONTAL-CORTEX
INTRACEREBRAL POTENTIALS TO RARE TARGET AND DISTRACTER AUDITORY AND VISUAL-STIMULI .3. FRONTAL-CORTEX
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DOI：
10.1016/0013-4694(95)98476-o
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发表时间：
1995-04-01
期刊：
影响因子：
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通讯作者：
CLARKE, JM
中科院分区：
文献类型：
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作者：
BAUDENA, P;HALGREN, E;CLARKE, JM
在目标和非目标（干扰）罕见刺激的听觉辨别任务中，记录了36例患者991个额叶和罗兰周围部位（106个电极）的诱发电位（EP）。该任务的变体探讨了注意力，disabituation和刺激特征（包括模态）的影响。罕见的刺激诱发了广泛的三相波形，负，正和负峰分别在约210，280和390毫秒。该波形与称为N2 a/P3 a/慢波的头皮EP复合体一起识别，并与定向相关。它是由罕见的目标和分心的听觉和视觉刺激，以及罕见的刺激重复或遗漏。在大多数额叶轨迹，N2 a/P3 a/SW振幅变化缓慢的距离。然而，大（120 μ V）的P3 as与陡峭的电压梯度横向观察，特别是在额下沟附近，和明确的倒置的P3 a注意到在眶额和前扣带皮层。额叶P3 a早于分心比目标刺激，但只有在某些网站和潜伏期差异远远小于观察到的头皮。额叶P3 a潜伏期明显短于头皮同时记录的P3 a潜伏期，并且通常也短于顶叶或颞叶的P3 a潜伏期。总之，这项研究表明，早期P3 a样活动，极性反转在短距离内内侧额叶，它有一个显着较短的潜伏期比类似的电位记录在颞叶和顶叶皮层。
Evoked potentials (EPs) were recorded from 991 frontal and peri-rolandic sites (106 electrodes) in 36 patients during an auditory discrimination task with target and non-target (distracter) rare stimuli. Variants of this task explored the effects of attention, dishabituation and stimulus characteristics (including modality). Rare stimuli evoked a widespread triphasic waveform with negative, positive and negative peaks at about 210, 280 and 390 msec, respectively. This waveform was identified with the scalp EP complex termed the N2a/P3a/slow wave and associated with orienting. It was evoked by rare target and distracter auditory and visual stimuli, as well as by rare stimulus repetitions or omissions. Across most frontal trajectories, N2a/P3a/SW amplitudes changed only slowly with distance. However, large (120 mu V) P3as with steep voltage gradients were observed laterally, especially near the inferior frontal sulcus, and clear inversions of the P3a were noted in the orbito-frontal and the anterior cingulate cortices. The frontal P3a was earlier to distracter than to target stimuli, but only in some sites and with a latency difference much smaller than that observed at the scalp. Frontal P3a latencies were significantly shorter than those recorded simultaneously at the scalp and often were also shorter than P3a latency in the parietal or temporal lobes. In summary, this study demonstrates an early P3a-like activity that polarity inverts over short distances in the medial frontal lobe, and that it has a significantly shorter latency than similar potentials recorded in the temporal and parietal cortices.