正常青年人失匹配负波检查

摘要

目的：探讨失匹配负波（mismatch negativity，MMN）检查在正常青年人中的特点，并分析阅读状态和集中注意力时MMN检查的结果有无差异。方法对12例青年女性(年龄29-31y，平均30.08y)和18例青年男性(年龄27-34y，平均30.22y)行MMN检查，所有受试者均行听性脑干反应（ABR）阈值检查，确定ABR阈值，MMN检查在受试者在阅读状态和集中注意力状态时分别检测，采用oddball刺激方式，给予短纯音刺激，偏差刺激声为2000Hz，概率为20%，标准刺激为1000 Hz，概率为80%，刺激频率为1.1次/s，刺激声强度为ABR阈上50dB nHL；观察MMN潜伏期及波幅的特点。结果所有受试者ABR阈值均≤25 dB nHL。每例受试者均可引出MMN波形，女性在阅读状态下MMN潜伏期为159.57±20.64 ms，波幅为3.82±1.38 uV，在集中注意力状态下MMN潜伏期为155.96±17.51 ms，波幅为4.28±1.89 uV，经配对t检验潜伏期和波幅在两种状态下无显著差异；男性在阅读状态下MMN潜伏期为150.48±19.57 ms，波幅为3.75±1.27 uV，在集中注意力状态下MMN潜伏期为144.81±15.42 ms，波幅为3.99±1.34 uV，经配对t检验潜伏期和波幅在两种状态下无显著差异；经独立样本t检验，男女在上述两种状态下MMN波幅和潜伏期均无显著差异。结论正常青年男女均能引出MMN波形，男女之间MMN检查的波幅和潜伏期无差异，阅读状态和集中注意力状态对MMN检查的波幅和潜伏期无影响。%Objective To investigate the characteristics of mismatch negativity (MMN) in normal young people, and ef-fects of status of attention on MMN results. Methods MMN tests were performed on 12 young females (age 29-31years, aver-age 30.08 years) and 18 young males (age 27-34 years, average 30.22 years). In all cases, acoustic brainstem responses (ABR) were tested first so as to identify the ABR threshold. MMN were tested under the status of reading or concentrating. The odd-ball model was used in MMN testing, with brief pure tones used as the stimulus. The deviation frequency was 2000 Hz with a rate of 20%, and the standard frequency was 1000 Hz with a rate of 80%. The stimulus was delivered at 50 dB above the ABR threshold at a rate of 1.1/sec. The latency and amplitude of MMN in each group and under different attention status were analyzed. Results In all cases, ABR thresholds were≤25 dB nHL, and MMN was successfully induced. In the female group, the latency of MMN was 159.57 ± 20.64 ms with an average amplitude of 3.82 ± 1.38 uV when reading, and 155.96 ± 17.51 ms with an average amplitude of 4.28±1.89 uV when concentrating, showing no statistically significant difference on paired-t test. In the male group, the latency of MMN was 150.48 ± 19.57 ms with an average amplitude of 3.75 ± 1.27 uV when reading, and 144.81±15.42 ms with an average amplitude of 3.99±1.34 uV when concentrating, again showing no statistically significant dif-ference by paired t-test. By independent t-test, the latency and the amplitude differences were not statistically significant be-tween the female and male groups under either attention status. Conclusion MMN can be easily induced in normal young peo-ple, with no significant differences in latency or amplitude between males and females. Status of attention does not affect the re-sults of MMN test.