神经影像学研究的证据表明,重度抑郁症患者的自杀意念与多个大脑区域的结构和功能异常相关[1-2],尤其是执行功能障碍。而前额叶背外侧皮质(DLPFC)与情绪症状之间存在很强的关联,但DLPFC功能是否可以成为有自杀意念抑郁症的生物标志物尚无定论[3]。
近红外脑功能成像技术(fNIRS)可以利用650-1000nm之间的光源,穿透有机组织并被血红蛋白吸收,通过神经血管耦合机制反映脑功能变化。一方面,它相对便宜、便携、易于开展,并且可以提供与功能性磁共振(fMRI)相当的时间分辨率,且能适用于多种自然环境[4-6]。
研究表明,自传体记忆功能障碍是情感障碍的标志,可能是抑郁症患者存在过度负面情绪的主要原因,它可以推动和预测抑郁症的发作和维持,而改善该功能可以缓解抑郁症状[7]。
因此,华中科技大学张妍教授团队联合江汉大学在《Journal of Affective Disorders》(IF=6.533)杂志上发表了一篇研究[8],该研究利用fNIRS探索在情绪自传体记忆测试时患者DLPFC的血流动力学变化,这些受试者为有/无自杀意念的年轻抑郁症患者。
用情感图片作为线索,勾起受试者对过去某些特定情节的记忆等,以唤起受试者的情绪。试验范式如下:
采用武汉资联虹康生产的BS-7000设备,16个发射光源和16个接收探头,共53通道,通道排布如下:
表1 p值来自 χ2检验和单因素方差分析, "a"代表单因素方差分析, "b"代表χ2检验
图3 (A)在EAMT期间,健康对照组与无自杀意念抑郁组在负面情绪下HbO水平的变化。
(B)健康对照组和无自杀意念抑郁组负情绪下左DLPFC平均HbO分布的直方图。*:p<0.05
图4 (A)在EAMT期间,健康对照组与无自杀意念抑郁组在负面情绪下HbO水平的变化。
(B)健康对照组和自杀意念抑郁组正性情绪下右DLPFC平均HbO分布的直方图。*:p<0.05
五、结论
1、有自杀意念的抑郁症个体在右侧DLPFC的执行功能方面存在一定的缺陷[1]Du, L., Zeng, J., Liu, H., Tang, D., Meng, H., Li, Y., Fu, Y., 2017. Fronto-limbic disconnection in depressed patients with suicidal ideation: a resting-state functional connectivity study. [J]. Affect. Disord. 215, 213-217
[2]Minzenberg, M.J., Lesh, T.A., Niendam, T.A., Cheng, Y., Carter, C.S., 2016. Conflictrelated anterior cingulate functional connectivity is associated with past suicidal ideation and behavior in recent-onset psychotic major mood disorders.[J]. Neuropsychiatry Clin. Neurosci. 28 (4), 299-305.
[3]Y.Q. Lee, G.W.N. Tay, C.S.H. Ho.Clinical utility of functional near-infrared spectroscopy for assessment and prediction of suicidality: a systematic review.[J]. Frontiers in Psychiatry, 12 (2021),716276.
[4]Ho, C.S.H., Lim, L.J.H., Lim, A.Q., Chan, N.H.C., Tan, R.S., Lee, S.H., Ho, R.C.M., 2020. Diagnostic and predictive applications of functional near-infrared spectroscopy for major depressive disorder: a systematic review. [J].Frontiers in Psychiatry 11, 378.
[5]Scholkmann, F., Kleiser, S., Metz, A.J., Zimmermann, R., Mata Pavia, J., Wolf, U., Wolf, M., 2014. A review on continuous wave functional near-infrared spectroscopy and imaging instrumentation and methodology. NeuroImage 85 (Pt 1), 6–27.
[6]Chenghua Gu et al. Caveolae in CNS arterioles mediate neurovascular coupling Brian. Nature. 2020.[7]Sumner, J.A., Mineka, S., Adam, E.K., Craske, M.G., Vrshek-Schallhorn, S., WolitzkyTaylor, K., Zinbarg, R.E., 2014. Testing the CaR-FA-X model: investigating the mechanisms underlying reduced autobiographical memory specificity in individuals with and without a history of depression. J. Abnorm. Psychol. 123 (3), 471–486.
[8]Zheng M, Da H, Pan X, et al. Dorsolateral prefrontal activation in depressed young adults with and without suicidal ideation during an emotional autobiographical memory task: A fNIRS study.[J] J Affect Disord. 2023;326:216-224.