Biomedical Imaging Technology Center, Department of Biomedical Engineering, Emory University and Georgia Institute of Technology, 101 Woodruff Circle, Atlanta, GA 30322, USA.
Hum Brain Mapp. 2011 May;32(5):759-70. doi: 10.1002/hbm.21059.
Prenatal cocaine exposure (PCE) is associated with attention/arousal dysregulation and possible inefficiencies in some cognitive functions. However, the neurobiological bases of these teratogenic effects have not been well characterized. Because activities in the default mode network (DMN) reflect intrinsic brain functions that are closely associated with arousal regulation and cognition, alterations in the DMN could underlie cognitive effects related to PCE. With resting-state and task activation functional magnetic resonance imaging (fMRI), this study investigated the possible PCE related changes in functional brain connectivity and brain activation in the DMN. In the resting state, the PCE group was found to have stronger functional connectivity in the DMN, as compared to the nonexposed controls. During a working memory task with emotional distracters, the PCE group exhibited less deactivation in the DMN and their fMRI signal was more increased by emotional arousal. These data revealed additional neural effects related to PCE, and consistent with previous findings, indicate that PCE may affect behavior and functioning by increasing baseline arousal and altering the excitatory/inhibitory balancing mechanisms involved in cognitive resource allocation.
产前可卡因暴露（PCE）与注意力/觉醒调节障碍以及某些认知功能的效率低下有关。然而，这些致畸作用的神经生物学基础尚未得到很好的描述。由于默认模式网络（DMN）的活动反映了与觉醒调节和认知密切相关的内在大脑功能，因此 DMN 的改变可能是与 PCE 相关的认知效应的基础。本研究采用静息态和任务激活功能磁共振成像（fMRI）技术，研究了 DMN 中可能与 PCE 相关的功能连接和脑激活的变化。在静息状态下，与未暴露于可卡因的对照组相比，PCE 组的 DMN 功能连接更强。在带有情绪干扰的工作记忆任务中，PCE 组的 DMN 去激活程度较低，其 fMRI 信号受情绪唤醒的影响更大。这些数据揭示了与 PCE 相关的额外神经效应，并与之前的研究结果一致，表明 PCE 可能通过增加基线觉醒和改变参与认知资源分配的兴奋/抑制平衡机制来影响行为和功能。
