School of Psychology, Cardiff University, Cardiff, UK.
Nutr Neurosci. 2012 Jul;15(4):176-85. doi: 10.1179/1476830512Y.0000000009. Epub 2012 Apr 3.
Chewing gum has been shown to reliably increase subjective alertness whereas the effects on attention are more variable. It has been suggested that chewing gum only enhances attention when the person has been performing a task for some time.
The current research aimed to investigate if time-on-task trends enhancing effects of chewing gum could be observed in alertness and attention during and following chewing.
Study 1 used tests of reported mood, including reported mood, and tests of attention (categoric search, focussed attention, simple reaction time, and vigilance). These tasks were performed shortly after the start of chewing. Study 2 examined effects of previous and current chewing on reported alertness and the attention tests.
Study 1 showed that chewing gum increased reported alertness and hedonic tone and improved performance on the categoric search task. Chewing gum maintained reported alertness across sessions in study 2. In the first experimental session of study 2 gum improved categoric search performance, and during the second session gum broadened focus of attention and quickened vigilance reaction time. This effect on vigilance reaction time was moderated by time-on-task, with an initial negative effect being replaced by a positive effect.
The results confirm the robust effect of chewing gum on reported alertness and show that changes in the effects of chewing gum on attention require further investigation. Future research may also determine underlying mechanisms for an alerting effect.
咀嚼口香糖已被证明能可靠地提高主观警觉性，而其对注意力的影响则更为多变。有人认为，只有当一个人已经执行某项任务一段时间后，咀嚼口香糖才能增强注意力。
本研究旨在调查在咀嚼过程中和咀嚼结束后，是否可以观察到随着任务时间的推移，咀嚼口香糖对警觉性和注意力的增强作用。
研究 1 使用了报告情绪的测试，包括报告情绪和注意力测试（类别搜索、专注注意力、简单反应时间和警戒）。这些任务在咀嚼开始后不久进行。研究 2 考察了先前和当前咀嚼对报告警觉性和注意力测试的影响。
研究 1 表明，咀嚼口香糖可以提高报告警觉性和愉悦感，改善类别搜索任务的表现。在研究 2 中，咀嚼口香糖在整个实验过程中保持了报告警觉性。在研究 2 的第一个实验会话中，口香糖改善了类别搜索表现，而在第二个会话中，口香糖拓宽了注意力焦点并加快了警戒反应时间。这种对警戒反应时间的影响受到任务时间的调节，最初的负面效应被正面效应所取代。
结果证实了咀嚼口香糖对报告警觉性的强烈影响，并表明咀嚼口香糖对注意力的影响的变化需要进一步研究。未来的研究也可能确定警觉作用的潜在机制。
