Age-related differences in sensitivity to small changes in frequency assessed with cortical evoked potentials
Age-related differences in sensitivity to small changes in frequency assessed with cortical evoked potentials
复制标题
DOI：
10.1016/j.heares.2008.05.005
复制
发表时间：
2008-09-01
期刊：
影响因子：
2.8
通讯作者：
Dubno, Judy R.
中科院分区：
文献类型：
--
作者：
Harris, Kelly C.;Mills, John H.;Dubno, Judy R.
作为听觉处理中与年龄相关的变化研究的一部分，在听力正常的年轻人和老年人中，使用皮层听觉诱发电位P1-N1-132来评估对频率小变化的敏感性。行为测量显示，与年龄相关的歧视强度和频率差异在低频率时大于高频率时。然而，研究中存在显著的个体差异和模棱两可的结果。这种可变性可能反映了任务和程序的差异，以及听觉灵敏度和注意力水平等主体变量。为了尽量减少这些被试变量，P1-N1-P2反应采用被动聆听范式进行调查。研究对象是10名年轻人和10名老年人。P1-N1-P2在70dB声压级下连续的500 hz和3000 hz纯音中被150 ms的频率变化所激发。P1-N1-P2阈值定义为引起P1-N1-P2反应所需的最小频率变化。此外，P1-N1-P2阈值存在频率依赖的衰老效应，老年人对频率变化的敏感性明显低于年轻人，500 Hz时的年龄相关差异明显大于3000 Hz。在500和3000 Hz时，反应潜伏期和P1-N1-P2反应幅度的年龄相关变化也很明显。这些结果与中央听觉系统的年龄相关变化是一致的，并表明老年人频率识别能力的变化可能部分与听觉处理前注意水平的变化有关。(C) 2008 Elsevier B.V.版权所有
As part of an ongoing study of age-related changes in auditory processing, sensitivity to small changes in frequency were assessed using the cortical auditory evoked potential, P1-N1-132, in younger and older adults with normal hearing. Behavioral measures have shown age-related differences in intensity and frequency discrimination that are larger at lower than higher frequencies. However, substantial individual differences and equivocal results among studies have been reported. This variability may reflect differences in tasks and procedures, as well as subject variables, such as hearing sensitivity and level of attention. To minimize these subject variables, the P1-N1-P2 response was investigated using a passive listening paradigm. Subjects were 10 younger and 10 older adults. The P1-N1-P2 was elicited by a 150-ms change in frequency in otherwise continuous 500-Hz and 3000-Hz pure tones presented at 70dB SPL. P1-N1-P2 threshold was defined as the smallest change in frequency needed to evoke a P1-N1-P2 response. Furthermore, a frequency-dependent aging effect was observed for P1-N1-P2 thresholds, such that older subjects were significantly less sensitive to the frequency change than younger subjects, with significantly larger age-related differences at 500 Hz than at 3000 Hz. Age-related changes in response latencies and amplitude of the P1-N1-P2 response were also evident at 500 and 3000 Hz. These results are consistent with age-related changes in the central auditory system and suggest that changes in frequency discrimination abilities of older adults may be, in part, related to changes in preattentive levels of auditory processing. (C) 2008 Elsevier B.V. All rights reserved.