Department of Anatomy and Neurobiology, Washington University School of Medicine, St. Louis, MO, USA.
Neuroimage. 2012 Nov 15;63(3):1001-10. doi: 10.1016/j.neuroimage.2012.08.011. Epub 2012 Aug 11.
Neurophysiological processes underlying auditory memory and attention are impaired in habitually short sleepers. The aim of this study was to use dynamic causal modeling (DCM) to study the mechanisms of these impairments in short sleepers. Eight normal sleepers (total sleep time (TST)=7-8h) and nine habitual short sleepers (TST ≤ 6 h) participated. The time in bed was increased from habitual (≤ 6 h) to extended (~8.5h) for one week in the short sleep group. Event related potentials (ERPs) were collected using an auditory novelty task in "IGNORE" and "ATTEND" conditions. Fourteen DCM models were considered using different configurations of connections among the following six areas: left and right primary auditory cortices, superior temporal gyri (STG), and inferior temporal gyri (IFG). After fitting the ERPs to the 14 models (separately for the IGNORE and ATTEND conditions), the best model (across subjects) was chosen using the Bayesian model comparison. For both conditions, the connection from right-STG to right-IFG for normal sleepers was significantly greater than habitual short sleepers. This connection did not differ in habitual short sleepers before and after one week of extended sleep time. This connection for normal sleepers was not significantly greater than the habitual short sleepers after one week of extended sleep. These results show that the deficiency of novelty processing, seen in short sleepers, can be explained by the differences in connectivity of the pathway between frontal and temporal brain areas as compared to the normal sleepers. In addition, one week of extended time in bed was not enough to fully normalize this neuronal pathway between STG and IFG in short sleepers.
习惯性睡眠不足者的听觉记忆和注意力的神经生理过程受损。本研究旨在使用动态因果建模（DCM）来研究短睡眠者这些损伤的机制。八名正常睡眠者（总睡眠时间（TST）=7-8h）和九名习惯性短睡眠者（TST ≤ 6 h）参与了研究。短睡眠组的睡眠时间从习惯性（≤ 6 h）增加到延长（约 8.5h）一周。在“忽略”和“注意”条件下使用听觉新颖性任务收集事件相关电位（ERPs）。考虑了 14 个 DCM 模型，这些模型使用以下六个区域（左、右初级听觉皮层、颞上回（STG）和颞下回（IFG））之间的连接的不同配置。在将 ERPs 拟合到 14 个模型（分别针对 IGNORE 和 ATTEND 条件）之后，使用贝叶斯模型比较选择最佳模型（跨受试者）。对于两种条件，正常睡眠者的右侧 STG 到右侧 IFG 的连接明显大于习惯性短睡眠者。在一周延长睡眠时间前后，习惯性短睡眠者之间的这种连接没有差异。一周延长睡眠时间后，正常睡眠者的这种连接并不明显大于习惯性短睡眠者。这些结果表明，在短睡眠者中观察到的新颖性处理不足可以通过与正常睡眠者相比，额颞脑区之间的连接差异来解释。此外，一周的延长睡眠时间不足以完全使短睡眠者的 STG 和 IFG 之间的这条神经元通路正常化。
