Department of Rehabilitation for Sensory Functions, Research Institute, National Rehabilitation Center for Persons with Disabilities, Saitama, Japan.
Hear Res. 2010 Jan;259(1-2):107-16. doi: 10.1016/j.heares.2009.10.011. Epub 2009 Oct 24.
Mismatch negativity (MMN) is a negative component of event-related brain potentials elicited by stimulus transitions. Stimulus duration transition also elicits MMN (duration MMN), with a magnitude that is related to the degree of duration change and the discrimination ability. The neural substrates of duration MMN have not yet been investigated. We therefore studied how duration transitions in an auditory stimulus train are represented in neurons in the primary auditory cortex of anesthetized guinea pigs. Two types of neuronal responses to the context of changes in stimulus duration were found. One was a reduced response as the duration of the preceding stimulus was increased. Second was an enhancement of the late components of the response including sustained and offset responses at the duration transition. The former may be explained by the previously proposed two-tone suppression, which is dependent on the preceding stimulus duration. The latter is likely to be caused by stimulus-specific adaptation that could be a possible neural generator of duration MMN.
失匹配负波（MMN）是由刺激转变引起的事件相关脑电位的负成分。刺激持续时间的转变也会引起 MMN（持续时间 MMN），其幅度与持续时间变化的程度和辨别能力有关。持续时间 MMN 的神经基础尚未被研究过。因此，我们研究了在麻醉豚鼠的初级听觉皮层中，听觉刺激序列中的持续时间转变是如何在神经元中被表示的。发现了两种对刺激持续时间变化的上下文的神经元反应类型。一种是随着前一个刺激的持续时间增加而减少的反应。第二种是对反应的后期成分的增强，包括在持续时间转变时的持续和消退反应。前者可以用先前提出的、依赖于前一个刺激持续时间的两音抑制来解释。后者可能是由刺激特异性适应引起的，这可能是持续时间 MMN 的一个潜在的神经发生器。
