Honda Yukiko, Watanabe Shoko, Nakamura Maiko, Miki Kensaku, Kakigi Ryusuke
Department of Integrative Physiology, National Institute for Physiological Sciences, Myodaiji, Okazaki 444-8585, Japan.
Brain Topogr. 2007 Fall;20(1):31-9. doi: 10.1007/s10548-007-0028-z. Epub 2007 Jul 20.
We recorded event-related potentials (ERPs) to investigate the interhemispheric difference of the N170 component for upright and inverted face perception in detail in fifteen healthy subjects. This is the first ERP study focusing on interhemispheric differences for face perception by showing faces in the hemifield. The face inversion effect, the prolonged latency and enhanced amplitude were found in both hemispheres. We found that the peak latency of the N170 following both upright and inverted face stimulation showed no significant difference between each hemisphere, though the N170 latency for the inverted face in the left hemisphere was shorter than that in the right hemisphere. The N170 recorded from the hemisphere ipsilateral to the stimulated hemifield showed unique findings. The interhemispheric time difference of the N170 between the right and the left hemispheres when the inverted face was presented in the left hemifield was significantly shorter than in the other three conditions. This unique finding may indicate that the conduction time from the right to the left for inverted face perception is faster than the other conditions, or that the left hemisphere specifically processed the inverted face very rapidly after receiving signals from the right hemisphere. If the N170 was generated by some, at least two, temporally overlapping activities, the different style of a summation of these activities may cause the unique findings found in this study. In conclusion, by presenting face stimuli in the hemifields, we could identify several new findings regarding the N170 component related to the face inversion effect.
我们记录了事件相关电位（ERP），以详细研究15名健康受试者在 upright 和 inverted 面孔感知中 N170 成分的半球间差异。这是第一项通过在半视野中呈现面孔来关注面孔感知半球间差异的ERP研究。在两个半球中均发现了面孔倒置效应、潜伏期延长和波幅增强。我们发现，upright 和 inverted 面孔刺激后 N170 的峰值潜伏期在各半球之间无显著差异，尽管左半球中 inverted 面孔的 N170 潜伏期比右半球短。从与受刺激半视野同侧的半球记录到的 N170 呈现出独特的结果。当在左半视野呈现 inverted 面孔时，右半球和左半球之间 N170 的半球间时间差明显短于其他三种情况。这一独特发现可能表明，对于 inverted 面孔感知，从右到左的传导时间比其他情况更快，或者左半球在从右半球接收到信号后，对 inverted 面孔进行了非常快速的特异性处理。如果 N170 是由一些（至少两个）时间上重叠的活动产生的，那么这些活动的不同总和方式可能导致了本研究中发现的独特结果。总之，通过在半视野中呈现面孔刺激，我们能够确定与面孔倒置效应相关的 N170 成分的几个新发现。
