Federal Institute for Occupational Safety and Health, Nöldnerstrasse 40-42, Berlin, Germany.
Int J Behav Med. 2012 Sep;19(3):359-71. doi: 10.1007/s12529-011-9181-6.
Working memory (WM) declines with ageing, and this may cause problems in older workers who have to do complex work requiring WM.
We tested the assumption that an increase in WM load negatively affects performance and results in impaired cardiovascular adaptation to changing task demands in older workers relative to younger ones.
Thirty-three younger (29 ± 3 years) and 32 older (55 ± 3 years) workers had to perform a visual 0-back (low WM load) and 2-back (high WM load) task. Heart rate (HR), heart rate variability (HRV), beat-to-beat blood pressure (BP) and baroreflex were registered.
In the high WM load condition, older adults responded more slowly and less accurately than younger adults, while no age effects in the low WM load condition were found. Older workers showed a higher systolic blood pressure (SBP) reactivity to high WM load as well as a diminished post-task recovery of SBP and HRV than younger workers. Factor analysis demonstrated a close relationship between HR, baroreflex and HRV and their modulation by a common factor ("vagal tone") in the younger group. By contrast, HR was more related to the "sympathetic" factor in the older group.
The data suggest that older workers as compared with younger ones are impaired in tasks requiring WM, which is accompanied by enhanced cardiovascular "costs" in terms of increased SBP and reduced vagal control over HR.
工作记忆（WM）随年龄增长而下降，这可能会给需要进行复杂工作的老年工人带来问题，因为这些工作需要 WM。
我们验证了以下假设，即 WM 负荷增加会对老年人的表现产生负面影响，导致他们对不断变化的任务需求的心血管适应能力受损，与年轻人相比更为明显。
33 名年轻（29±3 岁）和 32 名年长（55±3 岁）工人必须执行视觉 0 回（低 WM 负荷）和 2 回（高 WM 负荷）任务。记录心率（HR）、心率变异性（HRV）、逐拍血压（BP）和压力反射。
在高 WM 负荷条件下，老年人的反应速度比年轻人慢，准确性也较低，而在低 WM 负荷条件下则没有年龄差异。与年轻人相比，年长工人在高 WM 负荷下的收缩压（SBP）反应更高，以及 SBP 和 HRV 的任务后恢复能力降低。因子分析表明，在年轻组中，HR、压力反射和 HRV 及其通过共同因子（“迷走神经张力”）的调制之间存在密切关系。相比之下，在年长组中，HR 与“交感”因子更为相关。
数据表明，与年轻人相比，年长工人在需要 WM 的任务中表现较差，同时伴有 SBP 增加和 HR 迷走神经控制降低等心血管“代价”的增加。
