DelDonno Sophie R, Jenkins Lisanne M, Crane Natania A, Nusslock Robin, Ryan Kelly A, Shankman Stewart A, Phan K Luan, Langenecker Scott A
Department of Psychology, University of Illinois at Chicago, United States.
Department of Psychiatry, University of Illinois at Chicago, United States.
J Affect Disord. 2017 Oct 15;221:72-80. doi: 10.1016/j.jad.2017.06.014. Epub 2017 Jun 15.
Studying remitted Major Depressive Disorder (rMDD) facilitates a better understanding of neural mechanisms for risk, given that confounding effects of active symptoms are removed. Disrupted functional connectivity has been reported in multiple networks in MDD. However, no study to date of rMDD has specifically examined connectivity of the ventral striatum (VS), a region highly implicated in reward and motivation. We investigated functional connectivity of the VS in individuals with and without a history of MDD, and in relation to affective personality traits.
Forty-two individuals with rMDD and 28 healthy controls across two sites completed resting-state fMRI and the Behavioral Inhibition System/Behavioral Activation System Scale. Voxel-wise, whole-brain comparisons were conducted across and between groups for four seeds: left and right inferior VS (VSi), left and right superior VS (VSs).
VSs connectivity to temporal and subcortical regions including the putamen and amygdala was positive and greater in HCs compared to rMDD individuals. Across groups, VSi connectivity was positively correlated with trait reward-responsiveness in somatomotor regions. Across groups, VSs connectivity was positively correlated with trait drive, particularly in the putamen, parahippocampal, and inferior temporal gyrus, and was negatively associated with trait behavioral inhibition in the anterior cingulate, frontal gyri, and insula.
Limitations include scanning at two sites and using multiple comparisons.
Group connectivity differences emerged from the VSs rather than VSi. VSs showed associations with trait drive and behavioral inhibition, whereas VSi corrrelated with reward-responsiveness. Depression history and affective traits contribute meaningful and specific information about VS connectivity in understanding risk for MDD.
鉴于消除了当前症状的混杂效应，研究缓解期重度抑郁症（rMDD）有助于更好地理解风险的神经机制。已有报道称，抑郁症患者的多个脑网络存在功能连接中断。然而，迄今为止，尚无关于rMDD的研究专门考察腹侧纹状体（VS）的连接情况，该区域与奖励和动机密切相关。我们研究了有和没有MDD病史的个体中VS的功能连接情况，以及与情感性人格特质的关系。
来自两个研究地点的42名rMDD患者和28名健康对照者完成了静息态功能磁共振成像（fMRI）以及行为抑制系统/行为激活系统量表测试。以体素为基础，对四组种子点（左右下VS（VSi）、左右上VS（VSs））在组间和组内进行全脑比较。
与rMDD患者相比，健康对照者中VSs与包括壳核和杏仁核在内的颞叶及皮质下区域的连接呈正向且更强。在所有组中，VSi连接与躯体运动区域的特质奖励反应性呈正相关。在所有组中，VSs连接与特质驱力呈正相关，尤其是在壳核、海马旁回和颞下回，并且与前扣带回、额回和岛叶的特质行为抑制呈负相关。
局限性包括在两个研究地点进行扫描以及使用了多重比较。
组间连接差异出现在VSs而非VSi。VSs与特质驱力和行为抑制有关，而VSi与奖励反应性相关。抑郁病史和情感特质为理解MDD风险时VS连接提供了有意义且特定的信息。
