Clinic for Psychiatry and Psychotherapy, Charité University Medicine, Campus Mitte, Berlin, Germany.
Neuroimage. 2011 Mar 15;55(2):818-24. doi: 10.1016/j.neuroimage.2010.12.031. Epub 2010 Dec 22.
The catechol-O-methyltransferase (COMT) Val(108/158)Met polymorphism of the dopamine system is essential for prefrontal cortex processing capacity and efficiency. In addition, dopaminergic neurotransmission is also associated with the sensory gating phenomenon protecting the cerebral cortex from information overload. It is however unclear if COMT genotype as a predictor of prefrontal efficiency modulates sensory gating on the level of the auditory cortex, i.e. the gating of the auditory evoked P50 and N100 components.
P50 and N100 gating and COMT Val(108/158)Met genotype were determined in 282 healthy subjects of German descent carefully screened for psychiatric or neurological disorders.
A significant effect of the COMT genotype was observed for N100 gating (F=4.510, df=2, p=0.012) but not for P50 gating (F=0.376, df=2, p=0.687). Contrast analysis showed that Met/Met individuals had poorer N100 gating compared to Val/Met (F=-12.931, p=0.003) and the Val/Val individuals (F=-11.056, p=0.057).
The results indicate that a high prefrontal efficiency as suggested by the COMT Met/Met genotype is associated with to a poor sensory gating of the N100 component. This would fit in a model where a high prefrontal processing capacity allows a pronounced afferent input of sensory information from the auditory cortex as reflected by a poor sensory gating. The more pronounced prefrontal contribution to the N100 compared to the P50 component may explain the exclusive genotype association with the N100 sensory gating. This preliminary model should be replicated and validated in future investigations.
多巴胺系统的儿茶酚-O-甲基转移酶（COMT）Val（108/158）Met 多态性对前额叶皮层的处理能力和效率至关重要。此外，多巴胺能神经传递也与感觉门控现象有关，该现象可防止大脑皮层受到信息过载的影响。然而，COMT 基因型作为前额叶效率的预测因子是否调节听觉皮层的感觉门控（即听觉诱发电位 P50 和 N100 成分的门控）尚不清楚。
在 282 名德国血统的健康受试者中确定了 P50 和 N100 门控和 COMT Val（108/158）Met 基因型，这些受试者经过仔细筛选，排除了精神或神经障碍。
观察到 COMT 基因型对 N100 门控有显著影响（F=4.510，df=2，p=0.012），但对 P50 门控没有影响（F=0.376，df=2，p=0.687）。对比分析表明，Met/Met 个体的 N100 门控较差，与 Val/Met（F=-12.931，p=0.003）和 Val/Val 个体（F=-11.056，p=0.057）相比。
结果表明，COMT Met/Met 基因型提示的前额叶效率较高与 N100 成分的感觉门控较差有关。这符合一种模型，即高前额叶处理能力允许来自听觉皮层的感觉信息传入明显增加，表现为感觉门控较差。与 P50 成分相比，前额叶对 N100 的贡献更为明显，这可能解释了基因型与 N100 感觉门控的唯一关联。该初步模型应在未来的研究中进行复制和验证。
