Center for Lifespan Changes in Brain and Cognition, Department of Psychology, University of Oslo, Oslo, Norway.
Department of Psychology, University of Oslo, Oslo, Norway.
Brain Struct Funct. 2018 Dec;223(9):4337-4349. doi: 10.1007/s00429-018-1755-5. Epub 2018 Sep 18.
Maturation of attentional processes is central to cognitive development. The electrophysiological P300 is associated with rapid allocation of attention, and bridges stimulus and response processing. P300 is among the most studied and robust electrophysiological components, but how different subcomponents of the P300 develop from childhood to adulthood and relate to structural properties of the cerebral cortex is not well understood. We investigated age-related differences in both early visual and P300 components, and how individual differences in these components are related to cortical structure in a cross-sectional sample of participants 8-19 years (n = 86). Participants completed a three-stimulus visual oddball task while high-density EEG was recorded. Cortical surface area and thickness were estimated from T1-weighted MRI. Group-level blind source separation of the EEG data identified two P300-like components, a fronto-central P300 and a parietal P300, as well as a component reflecting N1 and P2. Differences in activity across age were found for the parietal P300, N1 and P2, with the parietal P300 showing stronger activity for older participants, while N1 and P2 were stronger for younger participants. Stronger P300 components were positively associated with task performance, independently of age, while negative associations were found for P2 strength. Parietal P300 strength was age-independently associated with larger surface area in a region in left lateral inferior temporal cortex. We suggest that the age differences in component strength reflect development of attentional mechanisms, with increased brain responses to task-relevant stimuli representing an increasing ability to focus on relevant information and to respond accurately and efficiently.
注意过程的成熟是认知发展的核心。电生理 P300 与注意力的快速分配有关，它连接着刺激和反应处理。P300 是研究最多、最稳健的电生理成分之一，但不同的 P300 子成分如何从儿童期到成年期发展，以及与大脑皮层的结构特性如何相关，目前还不太清楚。我们在一个 8-19 岁的参与者横断面样本中，研究了 P300 早期视觉和 P300 成分的年龄相关差异，以及这些成分的个体差异与皮质结构的关系（n=86）。参与者在完成三刺激视觉Oddball 任务时记录高分辨率 EEG。皮质表面积和厚度是从 T1 加权 MRI 估计的。对 EEG 数据进行的组级盲源分离，确定了两个 P300 样成分，一个额中央 P300 和一个顶叶 P300，以及一个反映 N1 和 P2 的成分。随着年龄的增长，顶叶 P300、N1 和 P2 的活动差异明显，顶叶 P300 表现出更强的活动，而 N1 和 P2 则表现出更强的活动。P300 成分越强，与任务表现呈正相关，与年龄无关，而 P2 强度则呈负相关。顶叶 P300 强度与左侧颞叶下外侧皮质区域的表面积大小独立相关，与年龄无关。我们认为，成分强度的年龄差异反映了注意机制的发展，对任务相关刺激的大脑反应增强，代表了更有能力专注于相关信息，并准确、高效地做出反应。
