Department of Neurology and Psychiatry, Sapienza University of Rome, Rome, Italy.
PLoS One. 2013 Jun 14;8(6):e65315. doi: 10.1371/journal.pone.0065315. Print 2013.
Examination of sensorimotor activation alone in multiple sclerosis (MS) patients may not yield a comprehensive view of cerebral response to task stimulation. Additional information may be obtained by examining the negative BOLD response (deactivation). Aim of this work was to characterize activation and deactivation patterns during passive hand movements in MS patients.
13 relapsing remitting-MS patients (RRMS), 18 secondary progressive-MS patients (SPMS) and 15 healthy controls (HC) underwent an fMRI study during passive right-hand movements. Activation and deactivation contrasts in the three groups were entered into ANOVA, age and gender corrected. Post-hoc analysis was performed with one-sample and two-sample t-tests. For each patient we obtained lesion volume (LV) from both T1- and T2-weighted images.
Activations showed a progressive extension to the ipsilateral brain hemisphere according to the group and the clinical form (HC<RRMS<SPMS). Significant deactivation of the ipsilateral cortical sensorimotor areas was reduced in both patient groups with respect to HC. Deactivation of posterior cortical areas belonging to the default mode network (DMN), was increased in RRMS, but not in SPMS, with respect to HC. The amount of activation in the contralateral sensorimotor cortex was significantly correlated with that of deactivation in the DMN in HC and RRMS, but not in SPMS. Both increased activation and decreased deactivation patterns correlated with LV.
In RRMS patients, increased cortical activation was associated with increased deactivation of the posterior cortex suggesting a greater resting-state activity in the DMN, probably aimed at facilitating sensorimotor circuit engagement during task performance. In SPMS the coupling between increased sensorimotor activation/increased DMN deactivation was not observed suggesting disorganization between anticorrelated functional networks as a consequence of a higher level of disconnection.
在多发性硬化症（MS）患者中仅检查感觉运动激活可能无法全面了解大脑对任务刺激的反应。通过检查负 BOLD 反应（去激活）可以获得更多信息。本研究旨在描述 MS 患者在进行被动手部运动时的激活和去激活模式。
13 例复发缓解型 MS 患者（RRMS）、18 例继发进展型 MS 患者（SPMS）和 15 例健康对照者（HC）在进行右侧手部被动运动时进行 fMRI 研究。对三组的激活和去激活对比进行方差分析，年龄和性别校正。进行单样本和两样本 t 检验的事后分析。对每位患者，我们从 T1 加权和 T2 加权图像中获得病变体积（LV）。
激活随着组和临床形式（HC<RRMS<SPMS）逐渐扩展到对侧大脑半球。与 HC 相比，两组患者对侧皮质感觉运动区的去激活显著减少。与 HC 相比，属于默认模式网络（DMN）的后部皮质区域的去激活在 RRMS 中增加，但在 SPMS 中没有增加。对侧感觉运动皮质中的激活量与 HC 和 RRMS 中 DMN 的去激活量显著相关，但在 SPMS 中则没有相关性。增加的激活和减少的去激活模式均与 LV 相关。
在 RRMS 患者中，皮质激活增加与后部皮质去激活增加相关，这表明 DMN 的静息态活动增加，可能旨在促进任务执行期间感觉运动回路的参与。在 SPMS 中，未观察到增加的感觉运动激活/增加的 DMN 去激活之间的耦合，这表明由于更高水平的脱连接，反相关功能网络之间的组织紊乱。
