Cognitive Neuroscience Section, IRCCS San Giovanni di Dio Fatebenefratelli, Brescia, Italy.
Neurobiol Aging. 2012 Mar;33(3):625.e21-30. doi: 10.1016/j.neurobiolaging.2011.03.021. Epub 2011 May 6.
Physiological aging affects early sensory-perceptual processes. The aim of this experiment was to evaluate changes in auditory sensory memory in physiological aging using the Mismatch Negativity (MMN) paradigm as index. The MMN is a marker recorded through the electroencephalogram and is used to evaluate the integrity of the memory system. We adopted a new, faster paradigm to look for differences between 3 groups of subjects of different ages (young, middle age and older adults) as a function of short or long intervals between stimuli. We found that older adults did not show MMN at long interval condition and that the duration of MMN varied according to the participants' age. The current study provides electrophysiological evidence supporting the theory that the encoding of stimuli is preserved during normal aging, whereas the maintenance of sensory memory is impaired. Considering the advantage offered by the MMN paradigm used here, these data might be a useful reference point for the assessment of auditory sensory memory in pathological aging (e.g., in neurodegenerative diseases).
生理老化会影响早期感觉知觉过程。本实验旨在使用错配负波（MMN）范式作为指标，评估生理老化过程中听觉感觉记忆的变化。MMN 是一种通过脑电图记录的标志物，用于评估记忆系统的完整性。我们采用了一种新的、更快的范式，根据刺激之间的短或长间隔，观察不同年龄组（年轻、中年和老年）之间的差异。我们发现，老年组在长间隔条件下没有表现出 MMN，并且 MMN 的持续时间根据参与者的年龄而变化。本研究提供了电生理证据，支持这样一种理论，即在正常衰老过程中，刺激的编码得以保留，而感觉记忆的维持受到损害。考虑到这里使用的 MMN 范式的优势，这些数据可能是病理性衰老（例如，在神经退行性疾病中）评估听觉感觉记忆的有用参考点。
