Jaswal Rajbir, Gohel Suril, Biswal Bharat B, Alvarez Tara L
Department of Biomedical Engineering, New Jersey Institute of Technology , Newark, New Jersey.
Brain Connect. 2014 Oct;4(8):595-607. doi: 10.1089/brain.2013.0216. Epub 2014 Jun 19.
While functional magnetic resonance imaging (fMRI) has identified which regions of interests (ROIs) are functionally active during a vergence movement (inward or outward eye rotation), task-modulated coactivation between ROIs is less understood. This study tested the following hypotheses: (1) significant task-modulated coactivation would be observed between the frontal eye fields (FEFs), the posterior parietal cortex (PPC), and the cerebellar vermis (CV); (2) significantly more functional activity and task-modulated coactivation would be observed in binocularly normal controls (BNCs) compared with convergence insufficiency (CI) subjects; and (3) after vergence training, the functional activity and task-modulated coactivation would increase in CIs compared with their baseline measurements. A block design of sustained fixation versus vergence eye movements stimulated activity in the FEFs, PPC, and CV. fMRI data from four CI subjects before and after vergence training were compared with seven BNCs. Functional activity was assessed using the blood oxygenation level dependent (BOLD) percent signal change. Task-modulated coactivation was assessed using an ROI-based task-modulated coactivation analysis that revealed significant correlation between the FEF, PPC, and CV ROIs. Prior to vergence training, the CIs had a reduced BOLD percent signal change compared with BNCs for the CV (p<0.05), FEFs, and PPC (p<0.01). The BOLD percent signal change increased within the CV, FEF, and PPC ROIs (p<0.001) as did the task-modulated coactivation between the FEFs and CV as well as the PPC and CV (p<0.05) when comparing the CI pre- and post-training datasets. Results from the Convergence Insufficiency Symptom Survey were correlated to the percent BOLD signal change from the FEFs and CV (p<0.05).
虽然功能磁共振成像（fMRI）已确定在聚散运动（眼球向内或向外转动）期间哪些感兴趣区域（ROI）具有功能活性，但对ROI之间的任务调制共激活了解较少。本研究检验了以下假设：（1）在额叶眼区（FEF）、顶叶后皮质（PPC）和小脑蚓部（CV）之间会观察到显著的任务调制共激活；（2）与集合不足（CI）受试者相比，在双眼正常对照（BNC）中会观察到显著更多的功能活性和任务调制共激活；（3）在聚散训练后，与基线测量相比，CI受试者的功能活性和任务调制共激活会增加。持续注视与聚散眼球运动的组块设计刺激了FEF、PPC和CV中的活性。将四名CI受试者在聚散训练前后的fMRI数据与七名BNC的数据进行比较。使用血氧水平依赖（BOLD）百分比信号变化评估功能活性。使用基于ROI的任务调制共激活分析评估任务调制共激活，该分析揭示了FEF、PPC和CV ROI之间的显著相关性。在聚散训练前，与BNC相比，CI受试者在CV（p<0.05）、FEF和PPC（p<0.01）的BOLD百分比信号变化降低。当比较CI训练前和训练后的数据集时，CV、FEF和PPC ROI内的BOLD百分比信号变化增加（p<0.001），FEF与CV以及PPC与CV之间的任务调制共激活也增加（p<0.05）。集合不足症状调查的结果与FEF和CV的BOLD信号变化百分比相关（p<0.05）。
