Bullock T H, Karamürsel S, Achimowicz J Z, McClune M C, Başar-Eroglu C
Neurobiology Unit, Scripps Institution of Oceanography, La Jolla, CA.
Electroencephalogr Clin Neurophysiol. 1994 Jul;91(1):42-53. doi: 10.1016/0013-4694(94)90017-5.
Visual evoked potentials (VEPs) and omitted stimulus potentials (OSPs) are re-examined in scalp recordings from 19 healthy subjects. The principal finding is a distinction in form, latency and properties between OSPs in the conditioning stimulus range < 2 Hz, used in previous human studies, and those in the range > 5 Hz, used in previous studies of selected elasmobranchs, teleost fish and reptiles. We cannot find OSPs between 2 and 5 Hz. The high frequency ("fast," ca.6- > 40 Hz) and the low frequency ("slow," ca. 0.3-1.6 Hz) OSPs have different forms and latencies but both tend to a constant latency after the omission, over their frequency ranges, suggesting a temporally specific expectation. Fast OSPs (typically N120, P170-230 and later components including induced rhythms at 10-13 Hz) resemble an OFF effect, and require fixation but not attention to the interstimulus interval. Slow OSPs (usually P500-1100) require attention but not fixation; they are multimodal, unlike the fast OSPs. Based on cited data from fish and reptiles, fast OSPs probably arise in the retina, to be modified at each subsequent level. We have no evidence on the origin of slow OSPs. In both ranges not only large, diffuse flashes, but weak, virtual point sources (colored LEDs) meters away suffice. They are difficult to habituate. Both require very short conditioning periods. The transition from the single, rested VEP to the steady state response (SSR) at different frequencies is described. Around 8-15 Hz in most subjects larger SSRs suggest a resonance. Alternation between large and small SSR amplitude occurs around 4 Hz in some subjects and conditions of attention, and correlates with an illusion that the flash frequency is 2 Hz or is irregular. Jitter of the conditioning intervals greatly reduces the slow OSP but only slightly affects the fast OSP. Differences between scalp loci are described.
对19名健康受试者的头皮记录重新检查了视觉诱发电位（VEP）和遗漏刺激电位（OSP）。主要发现是，在先前人体研究中使用的条件刺激范围<2Hz的OSP与先前对某些板鳃亚纲动物、硬骨鱼和爬行动物研究中使用的范围>5Hz的OSP在形式、潜伏期和特性上存在差异。我们在2至5Hz之间未发现OSP。高频（“快”，约6->40Hz）和低频（“慢”，约0.3-1.6Hz）OSP具有不同的形式和潜伏期，但在遗漏后，在其频率范围内都趋于恒定潜伏期，这表明存在时间上特定的预期。快速OSP（通常为N120、P170-230及后续成分，包括10-13Hz诱导节律）类似于关闭效应，需要注视但不需要关注刺激间隔。慢速OSP（通常为P500-1100）需要关注但不需要注视；与快速OSP不同，它们是多模态的。根据引用的鱼类和爬行动物数据，快速OSP可能起源于视网膜，并在随后的每个层面进行修改。我们没有关于慢速OSP起源的证据。在这两个频率范围内，不仅大的、扩散的闪光，而且几米外微弱的虚拟点光源（彩色发光二极管）就足够了。它们很难产生习惯化。两者都需要非常短的条件刺激期。描述了从单个静止的VEP到不同频率下的稳态反应（SSR）的转变。在大多数受试者中，约8-15Hz时较大的SSR表明存在共振。在某些受试者和注意力条件下，约4Hz时SSR振幅会在大与小之间交替，这与闪光频率为2Hz或不规则的错觉相关。条件刺激间隔的抖动会大大降低慢速OSP，但只会轻微影响快速OSP。描述了头皮位点之间的差异。
