职业性接触低频噪声对认知的影响。

Effects of occupational exposure to low frequency noise on cognition.

作者信息

Gomes L M, Martinho Pimenta A J, Castelo Branco N A

机构信息

Oficinas Gerais de Matrial Aeronautico, Alverca, Portugal.

出版信息

Aviat Space Environ Med. 1999 Mar;70(3 Pt 2):A115-8.

PMID:10189166

Abstract

INTRODUCTION

Previous studies performed on groups of workers employed in the aeronautical industry revealed morphological vascular changes of the central nervous system (CNS) and some difficulty in attention and memory retention. The goal of this study is, therefore, to determine whether prolonged occupational exposure to large pressure amplitude (> or = 90 dB SPL) and low frequency (< or = 500 Hz) (LPALF) noise leads to cognitive deterioration.

METHODS

We observed 40 male workers employed as aircraft technicians, with average age of 43.3 yr (range 35-56, SD = 4.82) occupationally exposed to LPALF noise for a long period of time, average 22 yr (range 13-30, SD = 4.90), and 30 educationally- and age-matched male controls. None of the subjects had a history of alcoholism, and all were drug-free. The P300 event-related brain potential elicited with an auditory discrimination task was recorded and psychological tests (the Wechsler memory scale and the Toulouse-Piéron test) were performed.

RESULTS

The P300 latency was significantly longer (328.5 vs. 307.5 ms, F = 11.7, deg. signif.=0.001) and the amplitude significantly smaller (10.9 vs. 12.6, F = 4.3, deg. signif.=0.04) in the exposed group than in the controls. No significant differences were found in the results of the Toulouse-Piéron test. The different subscales of the Wechsler memory scale did not show any significant difference except in the immediate verbal memory, where the exposed workers were found to have poorer results than the controls (10.0 vs. 11.3, F = 5.6, deg. signif.=0.02). However, the memory quotient obtained from the Wechsler memory scale indicated a significant difference between both groups (101.8 vs. 108.3, F = 10.1, deg. signif.=0.002); exposed subjects presented lower results.

CONCLUSION

These findings suggest that prolonged exposure to LPALF noise might contribute to cognitive impairment and that the P300 event-related brain potential recording may be a valuable diagnostic tool.

摘要

引言

先前对航空工业从业人员群体进行的研究揭示了中枢神经系统（CNS）的形态学血管变化以及注意力和记忆保持方面的一些困难。因此，本研究的目的是确定长期职业暴露于大压力幅度（≥90 dB SPL）和低频（≤500 Hz）（LPALF）噪声是否会导致认知能力下降。

方法

我们观察了40名男性飞机技术人员，他们的平均年龄为43.3岁（范围35 - 56岁，标准差 = 4.82），长期职业暴露于LPALF噪声，平均暴露时间为22年（范围13 - 30年，标准差 = 4.90），并选取了30名在教育程度和年龄上与之匹配的男性作为对照。所有受试者均无酗酒史，且均未使用药物。记录了通过听觉辨别任务诱发的P300事件相关脑电位，并进行了心理测试（韦氏记忆量表和图卢兹 - 皮埃隆测试）。

结果

与对照组相比，暴露组的P300潜伏期显著延长（328.5对307.5毫秒，F = 11.7，显著性水平 = 0.001），波幅显著减小（10.9对12.6，F = 4.3，显著性水平 = 0.04）。图卢兹 - 皮埃隆测试结果未发现显著差异。韦氏记忆量表的不同子量表除即时言语记忆外均未显示出显著差异，在即时言语记忆方面，暴露组工人的结果比对照组差（10.0对11.3，F = 5.6，显著性水平 = 0.02）。然而，从韦氏记忆量表获得的记忆商表明两组之间存在显著差异（101.8对108.3，F = 10.1，显著性水平 = 0.002）；暴露组受试者的结果较低。