Applied Psychology and Human Development Department (OISE), University of Toronto, Toronto, Canada; Rotman Research Institute of Baycrest Centre, University of Toronto, Toronto, Canada.
Neuroimage. 2014 Jan 15;85 Pt 2:873-87. doi: 10.1016/j.neuroimage.2013.08.054. Epub 2013 Sep 2.
Cognitive control functions continue to improve from infancy until early adulthood, allowing flexible adaptation to a complex environment. However, it remains controversial how this development in cognitive capabilities is mediated by changes in cortical activity: both age-related increases and decreases of mediofrontal neural activity have been observed and interpreted as neural underpinnings of this functional development. To better understand this developmental process, we examined EEG theta activity in the mediofrontal region using a Go/No-go response control task. We found that both pre-stimulus baseline theta-power and theta-power during the response control task, without baseline-correction, decreased with age. Conversely, when task-related theta-power was baseline corrected (using a ratio method), it exhibited a positive developmental trajectory. The age-related theta-power increase was source-localized to the anterior cingulate cortex. This increase in theta activity also partially mediated age-related improvements in response control and was greatest in a condition that demanded greater effort. Theta activity in older children also showed greater temporal reliability across trials as measured by inter-trial phase-coherence. Interestingly, directly subtracting baseline activity from task-related activity did not yield significant developmental effects, which highlights the necessity of separating and contrasting the pre-stimulus baseline with task-related processing in the understanding of neurodevelopmental changes.
认知控制功能从婴儿期持续发展到成年早期，使人们能够灵活适应复杂的环境。然而，皮质活动的变化如何介导认知能力的这种发展仍然存在争议：人们观察到并解释了中前额神经活动的年龄相关增加和减少，认为这是这种功能发展的神经基础。为了更好地理解这个发展过程，我们使用 Go/No-go 反应控制任务检查了中前额区域的 EEG theta 活动。我们发现，无论是在没有基线校正的预刺激基线 theta 功率还是在反应控制任务期间的 theta 功率，都随着年龄的增长而降低。相反，当使用比率方法对任务相关的 theta 功率进行基线校正时，它表现出积极的发展轨迹。与年龄相关的 theta 功率增加定位于前扣带皮层。theta 活动的这种增加部分介导了与年龄相关的反应控制的改善，在需要更大努力的条件下最大。年龄较大的儿童的 theta 活动在通过试验间相位相干性测量时，在试验间也表现出更大的时间可靠性。有趣的是，直接从任务相关活动中减去基线活动并没有产生显著的发展影响，这突出表明在理解神经发育变化时，需要将预刺激基线与任务相关处理分开并进行对比。
