图形异同判断ERP鉴别脑外伤后伪装认知损害的研究

发布时间：2018-09-09 13:26

【摘要】：【背景】脑外伤后认知障碍鉴定案例中，因鉴定结论与被鉴定人的赔偿额度或其他利益等直接相关，，伪装或夸大智力伤残程度的情况是相当普遍的。因此,在鉴定时，评估被鉴定人的自述症状是否真实可信或者是否存在伪装，尽量排除故意夸大或伪装的成分，并以此做出客观的鉴定结论，因此，探索并应用可靠的伪装识别技术至关重要。事件相关电位（event-related potentials, ERP）与认知、感觉等脑电活动相关，具有高时间精度，较少受被试主观意愿的影响，且认知事件可与刺激呈现的时间相关联，即锁时（time-lock）等特点，应用于测谎领域的具有独特优势。研究表明ERP内源性成分如P300是检测伪装的一个较好指征，利用P300波幅与潜伏期等参数探查伪装的脑认知过程和神经电生理机制具有可行性。ERP检测技术在伪装认知功能障碍中的探索及应用，可为法医学鉴定识别伪装提供客观、可行的电生理技术。【目的】参考二项必选数字记忆测验（BFDMT）的编制原理，根据伪装认知损伤者的心理学特征编制符合实验要求及ERP技术规范的图形异同判断刺激序列，比较正常对照组、模拟伪装组脑外伤合作组和脑外伤不合作组完成刺激序列时诱发的ERP各特征性成分的差异，并对各特征成分在伪装检测中的应用价值作出评价。【方法】根据二项必选数字记忆测验的结果将20例脑外伤患者分为合作组（男9例，女1例，年龄42.58岁±3.76岁）和不合作组（男8例，女2例，年龄39.77岁±7.34岁），采用Neuroscan ERP仪呈现图形异同判断刺激序列并同步记录脑电，选择10例正常志愿者（男5例，女5例，年龄25.87岁±1.47岁）作为合作对照组，另选择15例正常志愿者作为模拟伪装组（男10例，女5例，年龄24.37±1.35岁），同时检测二项必选数字记忆测验和图形异同判断ERP序列，获得BFDMT总分、容易分、困难分、偏因商数以及ERP各成分的波幅和潜伏期等观察指标，比较各组受试者的ERP特征性成分及差异。【结果】（1）正常对照组的BFDMT总分的均值（24）最高，脑外伤合作组次之（22.9），脑外伤不合作组（15.2），模拟伪装组（8.93）最低，组间差异比较有极显著统计学意义（P0.01）；外伤不合作组（5.2）、模拟伪装组（3.6）的困难项目分均低于正常对照组（12）和合作组（11.2）（P0.01），模拟伪装组虽低于外伤不合作组，但无统计学意义；外伤不合作组（21.8）、模拟伪装组(19.18)的偏因商数均高于正常对照组（0）和外伤合作组（0）（P0.01）。（2）图形异同判断刺激序列在正常对照组所引出N1、P2、N2、P3、N3波形较为明显，头皮分布以Cz、FCz、CPz点的各成分波形最显著且分化较好；外伤合作组相同图形引出的N2、P3潜伏期较正常对照组延长（P0.05），无关图形引出的P3波幅较正常对照组降低（P0.05），无关图形刺激较相同图形引出的P2、P3、N3潜伏期延长（P0.05），N3波幅升高（P0.05）；（3）外伤不合作组相同图形引出的P3潜伏期较正常对照组和外伤合作组延长（P0.01）；N3潜伏期较正常对照组延长（P0.05）；外伤不合作组无关图形刺激P3潜伏期较正常对照组和外伤合作组延长（P0.01）； N3潜伏期较正常对照组延长（P0.05）；N3波幅较正常对照组和外伤组降低（P0.05）；（4）模拟伪装组相同图形引出的P3潜伏期较外伤合作组、外伤不合作组缩短（P0.01），波幅较正常对照组、外伤合作组、外伤不合作组降低（P0.01）；N3潜伏期较正常对照组、外伤合作组、外伤不合作组缩短（P0.01），波幅较正常对照组、外伤合作组、外伤不合作组升高（P0.01）；无关图形引出的P3潜伏期较外伤合作组、外伤不合作组缩短（P0.01），波幅较正常对照组、外伤合作组、外伤不合作组降低（P0.01）；N3潜伏期较正常对照组、外伤合作组、外伤不合作组缩短（P0.01），波幅较正常对照组、外伤合作组、外伤不合作组升高（P0.01）；（5）正常对照组N3成分的脑电地形图在相同、无关两类刺激下主要激活部位为前额叶、顶叶，而外伤合作组伴有部分枕叶激活，外伤不合作组枕叶激活范围较外伤合作组更为广泛，枕叶激活反围较正常对照组小；相同图片刺激引起的脑区激活范围较无关刺激大；模拟伪装组枕叶激活范围较大，相同刺激下更为明显。组间比较发现脑区激活强度和范围以正常对照组最大，外伤合作组次之，外伤不合作组最小。【结论】本研究采用的图形异同判断刺激序列可引出较为稳定的ERP成分，图片刺激呈现后依次引出五个成分波，分别为N1（负向）、P2（正向）、N2（负向）、P3（正向）、N3（负向），其中N3的潜伏期和波幅有组间统计学意义，在伪装判断中可能是一项较为客观的电生理指标。
[Abstract]:[BACKGROUND] It is quite common to disguise or exaggerate the degree of mental disability in cases of post-traumatic cognitive impairment appraisal because the appraisal conclusion is directly related to the amount of compensation or other benefits of the appraised. Intentionally exaggerating or camouflaging components and making objective identification conclusions, therefore, it is essential to explore and apply reliable camouflage identification technology.
Event-related potentials (ERP) are associated with cognitive, sensory and other EEG activities, with high temporal accuracy, less affected by the subjective will of the subjects, and cognitive events can be associated with the time of stimulus presentation, that is, time-lock, which has unique advantages in the field of lie detection. For example, P300 is a good indication for detecting camouflage. It is feasible to explore the brain cognitive process and neuroelectrophysiological mechanism of camouflage by using parameters such as P300 amplitude and latency.
[Objective] According to the principle of binomial compulsory digital memory test (BFDMT), the stimulus sequence was compiled according to the psychological characteristics of the patients with disguised cognitive impairment. The stimulus sequence was judged by the similarities and differences between the two groups according to the experimental requirements and ERP specifications. The difference of each characteristic component of ERP was evaluated, and the application value of each characteristic component in camouflage detection was evaluated.
[Methods] According to the results of binomial compulsory digital memory test, 20 patients with traumatic brain injury were divided into cooperative group (9 males, 1 females, age 42.58 years (+3.76 years) and non-cooperative group (8 males, 2 females, age 39.77 years (+7.34 years). Neuroscan ERP was used to judge the stimulus sequence and record the EEG synchronously. Ten normal volunteers were selected. (5 males, 5 females, age 25.87 years (+1.47 years) as a co-operative control group, and 15 normal volunteers as a simulated camouflage group (10 males, 5 females, age 24.37 (+1.35 years)), while the binomial compulsory digital memory test and graphical similarities and differences to determine ERP sequence, BFDMT total score, easy to score, difficult score, partial factor quotient and ERP components were obtained. Amplitude and latency of the subjects were compared, and the ERP characteristic components of each group were compared.
[Results] The average score of BFDMT was the highest in the normal control group (24), followed by the cooperative group (22.9), the non-cooperative group (15.2) and the simulated camouflage group (8.93). The difference between the two groups was statistically significant (P 0.01); the difficult item scores of the non-cooperative group (5.2) and the simulated camouflage group (3.6) were lower than those of the normal control group (12) and the simulated camouflage group (8.93). In Co-operative Group (11.2) (P 0.01), simulated camouflage group (21.8), simulated camouflage group (19.18) had higher partial factor quotient than normal control group (0) and trauma Co-operative Group (0) (P 0.01). (2) The patterns of N1, P2, N2, P3, N3 were more distinct in the normal control group. Cz, FCz and CPz were the most prominent and well-differentiated components in scalp distribution. The latency of N2 and P3 induced by the same pattern in the traumatic cooperation group was longer than that in the normal control group (P 0.05), the amplitude of P3 induced by unrelated pattern was lower than that in the normal control group (P 0.05), and the latency of P2, P3, N3 induced by unrelated pattern stimulation was longer than that of the same pattern (P 0.05), and the latency of N3 induced by unrelated pattern stimulation was longer (P 0.05 The amplitude increased (P 0.05); (3) The incubation period of P3 in the non-cooperative group was longer than that in the normal control group and the traumatic cooperation group (P 0.01); the incubation period of N3 in the non-cooperative group was longer than that in the normal control group (P 0.05); the incubation period of P3 in the non-cooperative group was longer than that in the traumatic cooperation group (P 0.01); and the incubation period of N3 in the non-cooperative group was longer than that in the normal control group (P The latency of P3 in simulated camouflage group was shorter than that in traumatic cooperation group (P 0.01), the amplitude of P3 was shorter than that in normal control group, traumatic cooperation group and traumatic non-cooperation group (P 0.01), and the latency of N3 was lower than that in normal control group, traumatic cooperation group and traumatic non-cooperation group (P 0.01). The latency of P3 was shorter in the non-cooperative group than that in the traumatic group (P 0.01), the amplitude was shorter (P 0.01), the latency of N3 was shorter (P 0.01), the amplitude was lower (P 0.01), the latency of N3 was lower (P 0.01) and the latency of N3 was shorter (P 0.01). In the non-cooperative group, the amplitude was shorter (P 0.01), the amplitude was higher than that in the normal control group, the cooperative group and the non-cooperative group (P 0.01); (5) In the normal control group, the main activation sites of N3 were prefrontal lobe and parietal lobe under the same stimulation, but the cooperative group was accompanied by partial occipital lobe activation, and the non-cooperative group was accompanied by occipital lobe stimulation. The activation range of the occipital lobe in the simulated camouflage group was larger than that in the traumatic co-operation group, and the activation range of the occipital lobe was smaller than that in the normal control group. In group B, the injury group was the smallest.
[Conclusion] The pattern similarity and dissimilarity judgment stimulus sequence used in this study can lead to more stable ERP components. Five component waves, N1 (negative), P2 (positive), N2 (negative), P3 (positive) and N3 (negative), were drawn in turn after the picture stimulus was presented. The latency and amplitude of N3 were statistically significant, which may be a comparison in camouflage judgment. It is an objective electrophysiological index.
【学位授予单位】：华中科技大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：D919.1

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