事件相关电位仪联合多导生理心理测量仪在识别脑外伤后伪装记忆障碍中的应用研究

At present, the forensic assessment of the memory impairment due to traumatic brain injury mainly relies on subjective reporting of the examinee, as well as the knowledge and experience of the experts. It is difficult to identify the malingering or over-reporting of memory impairment. In this situation, it is an urgent problem to investigate some new and objective methods to assess the memory function in this area. ERP and Polygraph could index brain activities underlying revision of the mental representation induced by incoming stimuli, which is benefit for the assessment of memory function. The present study would use ERP and Polygraph to detecting malingering of memory impairment on patients with traumatic brain injury based on a mock CIT paradigm. Event-related Brain Potentials including P300, N200, N400, LPC and MMN physiological indices including skin conductance, respiration and finger pulse would be recorded analyzed to see whether they can identify the malingering. In addition, the intelligence, memory, attention, depression and anxiety would be quantified by scales; and in further the impact of these factors on the validity of ERP and Polygraph test would be analyzed. This study could provide some experimental data and experience for using the ERP and Polygraph in memory-related forensic assessments, which has the potential to resolve the bottleneck problem in this area.

目前，脑外伤后记忆障碍的评估多依赖于被鉴定人的主观陈述及鉴定人的知识和经验，对于被鉴定人伪装或夸大症状有时难以评判，研究新的客观的评估方法，是法医精神病学领域一个亟待解决的瓶颈问题。事件相关电位仪（ERP）及多导生理心理测量仪（Polygraph）可以实时反映个体在面对特定刺激时的神经生理反应，利于记忆障碍的客观评估。本项目拟联合ERP及Polygraph，对脑外伤患者及健康人群进行模拟伪装记忆障碍的测试，检测脑外伤患者在伪装记忆障碍时P300、N200、N400、LPC及MMN等脑电波的波形特征以及皮肤电、呼吸和脉搏等生理性指标的变化特征，明确ERP及Polygraph识别脑外伤后伪装记忆障碍的效度，并量化分析智力、记忆力、注意力以及焦虑抑郁情绪与ERP及Polygraph测试指标的相关性，以分析影响ERP及Polygraph测试效度的精神因素，为脑外伤后记忆障碍的客观评估提供实验数据。

目前，脑外伤后记忆障碍的评估多依赖于被鉴定人的主观陈述及鉴定人的知识和经验，对于被鉴定人伪装记忆障碍有时难以评判，研究新的客观的评估指标和方法是亟待解决的瓶颈问题。本项目结合事件相关电位仪（event-related potential, ERP）及多导生理心理测量仪（Polygraph），对96例脑外伤患者及92例健康人群进行模拟伪装长时和短时记忆障碍的识别测试。结果显示polygraph在健康对照组的长时记忆范式中有89人（96.7%）测试正确，短时记忆范式有88人（95.7%）测试正确；实验组的正确率在长时记忆范式中有62人（64.6%）测试正确，短时记忆范式中有64人（66.7%）测试正确。Polygraph在脑外伤组测试正确率偏低的主要原因是被试者的皮肤电基线不稳，对刺激无反应或反应非常小，导致无法评分，影响的因素包括智商和注意力水平低下以及淡漠症状；在皮肤电反应敏感，刺激反应大的脑外伤患者中，Polygraph的测试准确率较高且结果较为可靠。本研究中，ERP测试在健康对照组和脑外伤组的准确率在63.3 ~ 78.0%之间，脑外伤组和对照组之间未发现统计学差异。在健康对照组中，ERP对记忆内容和伪装记忆障碍的识别率显著低于Polygraph；在脑外伤组中其识别率与Polygraph相当，智商、注意力、淡漠和抑郁情绪均是影响测试准确性的潜在因素。相较于Polygraph，ERP用于识别记忆内容和伪记忆装障碍还处于初级阶段，实验范式和结局变量的选择以及解释还缺乏一致性结论，其应用于实际还需要更多的实际应用研究。