Centre for Brain and Cognitive Development, Birkbeck University of London, London, UK.
Department of Psychology, Cambridge University, Cambridge, UK.
Infancy. 2020 Sep;25(5):677-698. doi: 10.1111/infa.12356. Epub 2020 Aug 3.
Individual differences in infants' engagement with their environment manifest early in development and are noticed by parents. Three views have been advanced to explain differences in seeking novel stimulation. The optimal stimulation hypothesis suggests that individuals seek further stimulation when they are under-responsive to current sensory input. The processing speed hypothesis proposes that those capable of processing information faster are driven to seek stimulation more frequently. The information prioritization hypothesis suggests the differences in stimulation seeking index variation in the prioritization of incoming relative to ongoing information processing. Ten-month-old infants saw 10 repetitions of a video clip and changes in frontal theta oscillatory amplitude were measured as an index of information processing speed. Stimulus-locked P1 peak amplitude in response to checkerboards briefly overlaid on the video at random points during its presentation indexed processing of incoming stimulation. Parental report of higher visual seeking did not relate to reduced P1 peak amplitude or to a stronger decrease in frontal theta amplitude with repetition, thus not supporting either the optimal stimulation or the processing speed hypotheses. Higher visual seeking occurred in those infants whose P1 peak amplitude was greater than expected based on their theta amplitude. These findings indicate that visual sensory seeking in infancy is explained by a bias toward novel stimulation, thus supporting the information prioritization hypothesis.
婴儿在环境中参与的个体差异在发育早期就表现出来，并被父母注意到。有三种观点被提出来解释寻求新刺激的差异。最佳刺激假说认为，当个体对当前的感官输入反应不足时，他们会寻求进一步的刺激。处理速度假说提出，那些能够更快地处理信息的人会更频繁地寻求刺激。信息优先化假说则表明，在优先处理传入信息与正在进行的信息处理方面，刺激寻求指数的差异会有所不同。10 个月大的婴儿观看了 10 次视频剪辑，并且测量了额部 theta 振荡幅度的变化，作为信息处理速度的指标。当视频播放过程中随机出现棋盘格时，对视频进行短暂叠加，以响应棋盘格的刺激锁定 P1 峰值幅度，作为处理传入刺激的指标。父母报告的更高视觉寻求与 P1 峰值幅度的降低或额部 theta 幅度随重复的强烈降低无关，因此既不支持最佳刺激假说，也不支持处理速度假说。那些 P1 峰值幅度大于基于其 theta 幅度预期的婴儿，出现了更高的视觉寻求。这些发现表明，婴儿期的视觉感官寻求是由对新刺激的偏好所解释的，因此支持信息优先化假说。
