Alterations of the default mode network and cognitive impairment in patients with unilateral chronic tinnitus
Yu-Chen Chen1, Hong Zhang2, Youyong Kong3, Han Lv4, Yuexin Cai5, Huiyou Chen1, Yuan Feng1, Xindao Yin1
1Department of Radiology, Nanjing First Hospital, Nanjing Medical University, Nanjing 210006, China; 2Department of Radiology, The Affiliated Jiangning Hospital of Nanjing Medical University, Nanjing 211100, China; 3School of Computer Science and Engineering, Southeast University, Nanjing 210018, China; 4Department of Radiology, Beijing Friendship Hospital, Capital Medical University, Beijing 100071, China; 5Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510275, China
Correspondence to: Hong Zhang. Department of Radiology, The Affiliated Jiangning Hospital of Nanjing Medical University, No.168 Gushan Road, Nanjing 211100, China. Email:
yayiba2063@163.com; Xindao Yin, MD, PhD. Department of Radiology, Nanjing First Hospital, Nanjing Medical University, No.68, Changle Road, Nanjing 210006, China. Email:
y.163yy@163.com.
Background: Previous studies have demonstrated that cognitive impairment is linked with neurophysiological alterations in chronic tinnitus. This study aimed to investigate the intrinsic functional connectivity (FC) pattern within the default mode network (DMN) and its associations with cognitive impairment in tinnitus patients using a resting-state functional magnetic resonance imaging (rs-fMRI).
Methods: Thirty-five chronic unilateral tinnitus patients, and 50 healthy controls were recruited for rsfMRI scanning. Both groups were age, gender and education level well-matched. The posterior cingulate cortex (PCC) was chosen as the region of interest (ROI) for detecting the FC changes, and determining if these abnormalities were related to a specific cognitive performance and tinnitus characteristic.
Results: Relative to the healthy controls, tinnitus patients showed increased FC between the PCC and the right medial prefrontal cortex (mPFC). Moreover, the enhanced FC between the PCC and right mPFC was correlated with the poorer TMT-B scores (r=0.474, P=0.008). These correlations were adjusted by age, gender, education level, GM volume, and mean hearing thresholds. The enhanced FC was not correlated with other tinnitus characteristics or cognitive performances.
Conclusions: The enhanced FC pattern of the PCC that is correlated with cognitive impairment in chronic tinnitus patients, especially the executive dysfunction. Enhanced connectivity pattern within the DMN may play a crucial role in neurophysiological mechanism in tinnitus patients with cognitive dysfunction.
Keywords: Chronic tinnitus; functional connectivity (FC); resting-state functional magnetic resonance imaging (rs-fMRI); default mode network (DMN); posterior cingulate cortex (PCC)
Source:
http://qims.amegroups.com/article/view/22643/21887