Hirakawa Noriaki, Hirano Yoji, Nakamura Itta, Hirano Shogo, Sato Jinya, Oribe Naoya, Ueno Takefumi, Kanba Shigenobu, Onitsuka Toshiaki
Department of Neuropsychiatry, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Department of Neuropsychiatry, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan; Department of Psychiatry, Harvard Medical School and Neural Dynamics Laboratory, VA Boston Healthcare System, Boston, MA, USA.
J Affect Disord. 2017 Jun;215:225-229. doi: 10.1016/j.jad.2017.03.046. Epub 2017 Mar 19.
The mismatch negativity (MMN) component of the event-related potential and its magnetic counterpart, the MMNm, are generated by a mismatch between the physical features of a deviant stimulus and a neuronal sensory-memory trace produced by repetitive standard stimuli. Deficits in the MMN/MMNm have been reported in patients with major depression; however, the results are inconsistent. The present study investigated the pitch-MMNm in patients with major depression using whole-head 306-channel magnetoencephalography (MEG).
Twenty patients with major depression and 36 healthy subjects participated in this study. Subjects were presented with two sequences of auditory stimuli. One consisted of 1000Hz standard signals (probability=90%) and 1200Hz deviant signals (probability=10%), while the other consisted of 1200Hz standard (90%) and 1000Hz deviant signals (10%). Event-related brain responses to standard tones were subtracted from responses to deviant tones.
Major depressive patients showed significantly reduced magnetic global field power (GFP) of MMNm in the right hemisphere (p=0.02), although no significant MMNm reduction was observed in the left hemisphere (p=0.81). Additionally, patients with major depression showed significantly earlier bilateral MMNm peak latencies (p=0.004). No significant associations were observed between MMNm variables and demographic data/clinical variables within the patients.
We could not exclude the effects of antidepressants, mood stabilizers, or neuroleptics on the MMNm abnormalities found in patients with major depression. Sample size was also insufficient to permit subgroup analyses.
Patients with major depression exhibited reduced GFP of MMNm in the right hemisphere. The present study suggested that patients with major depression may have right hemispheric dominant preattentive dysfunction.
事件相关电位的失匹配负波（MMN）成分及其磁对应物MMNm，是由异常刺激的物理特征与重复标准刺激产生的神经元感觉记忆痕迹之间的失匹配所产生的。重度抑郁症患者中已报告存在MMN/MMNm缺陷；然而，结果并不一致。本研究使用全头306通道脑磁图（MEG）对重度抑郁症患者的音调MMNm进行了研究。
20名重度抑郁症患者和36名健康受试者参与了本研究。受试者被呈现两组听觉刺激序列。一组由1000Hz标准信号（概率=90%）和1200Hz异常信号（概率=10%）组成，而另一组由1200Hz标准信号（90%）和1000Hz异常信号（10%）组成。将对异常音调的反应减去对标准音调的事件相关脑反应。
重度抑郁症患者右半球MMNm的磁全局场功率（GFP）显著降低（p=0.02），尽管左半球未观察到显著的MMNm降低（p=0.81）。此外重度抑郁症患者双侧MMNm峰值潜伏期显著提前（p=0.004）。在患者中，未观察到MMNm变量与人口统计学数据/临床变量之间存在显著关联。
我们无法排除抗抑郁药、心境稳定剂或抗精神病药对重度抑郁症患者中发现的MMNm异常的影响。样本量也不足以进行亚组分析。
重度抑郁症患者右半球MMNm的GFP降低。本研究表明，重度抑郁症患者可能存在右半球优势的前注意功能障碍。
