Agyei Seth B, Holth Magnus, van der Weel F R Ruud, van der Meer Audrey L H
Department of Psychology, Norwegian University of Science and Technology, Norway.
Dev Sci. 2015 May;18(3):436-51. doi: 10.1111/desc.12221. Epub 2014 Aug 21.
Electroencephalogram (EEG) was used in infants at 3-4 months and 11-12 months to longitudinally study brain electrical activity as the infants were exposed to structured forwards and reversed optic flow, and non-structured random visual motion. Analyses of visual evoked potential (VEP) and temporal spectral evolution (TSE, time-dependent amplitude changes) were performed on EEG data recorded with a 128-channel sensor array. VEP results showed infants to significantly differentiate between the radial motion conditions, but only at 11-12 months where they showed shortest latency for forwards optic flow and longest latency for random visual motion. When the TSE results of the motion conditions were compared with those of a static non-flow dot pattern, infants at 3-4 and 11-12 months both showed significant differences in induced activity. A decrease in amplitudes at 5-7 Hz was observed as desynchronized theta-band activity at both 3-4 and 11-12 months, while an increase in amplitudes at 9-13 Hz was observed as synchronized alpha-band activity only at 11-12 months. It was concluded that brain electrical activities related to visual motion perception change during the first year of life, and these changes can be observed both in the VEP and induced activities of EEG. With adequate neurobiological development and locomotor experience infants around 1 year of age rely, more so than when they were younger, on structured optic flow and show a more adult-like specialization for motion where faster oscillating cell assemblies have fewer but more specialized neurons, resulting in improved visual motion perception.
在3至4个月和11至12个月大的婴儿中使用脑电图（EEG）进行纵向研究，观察婴儿在暴露于结构化的向前和反向光流以及非结构化的随机视觉运动时的脑电活动。对使用128通道传感器阵列记录的EEG数据进行视觉诱发电位（VEP）和时间频谱演变（TSE，随时间变化的幅度变化）分析。VEP结果显示，婴儿能够显著区分径向运动条件，但仅在11至12个月大时，他们对向前光流的潜伏期最短，对随机视觉运动的潜伏期最长。当将运动条件的TSE结果与静态非流动点状图案的结果进行比较时，3至4个月和11至12个月大的婴儿在诱发活动方面均表现出显著差异。在3至4个月和11至12个月大时，均观察到5至7Hz处的振幅降低，表现为去同步化的θ波段活动，而仅在11至12个月大时，观察到9至13Hz处的振幅增加，表现为同步化的α波段活动。研究得出结论，与视觉运动感知相关的脑电活动在生命的第一年发生变化，这些变化可以在VEP和EEG的诱发活动中观察到。随着足够的神经生物学发育和运动经验，1岁左右的婴儿比他们小时候更依赖结构化的光流，并且在运动方面表现出更像成人的专业化，即振荡更快的细胞集合中的神经元数量更少但更专业化，从而改善了视觉运动感知。
