Bloorview Research Institute, 150 Kilgour Road, Toronto, Ontario, Canada.
Biomed Eng Online. 2010 Feb 4;9:7. doi: 10.1186/1475-925X-9-7.
Dual-axis swallowing accelerometry has recently been proposed as a tool for non-invasive analysis of swallowing function. Although swallowing is known to be physiologically modifiable by the type of food or liquid (i.e., stimuli), the effects of stimuli on dual-axis accelerometry signals have never been thoroughly investigated. Thus, the objective of this study was to investigate stimulus effects on dual-axis accelerometry signal characteristics. Signals were acquired from 17 healthy participants while swallowing 4 different stimuli: water, nectar-thick and honey-thick apple juices, and a thin-liquid barium suspension. Two swallowing tasks were examined: discrete and sequential. A variety of features were extracted in the time and time-frequency domains after swallow segmentation and pre-processing. A separate Friedman test was conducted for each feature and for each swallowing task.
Significant main stimulus effects were found on 6 out of 30 features for the discrete task and on 5 out of 30 features for the sequential task. Analysis of the features with significant stimulus effects suggested that the changes in the signals revealed slower and more pronounced swallowing patterns with increasing bolus viscosity.
We conclude that stimulus type does affect specific characteristics of dual-axis swallowing accelerometry signals, suggesting that associated clinical screening protocols may need to be stimulus specific.
双轴吞咽加速计最近被提议作为一种非侵入性分析吞咽功能的工具。尽管已知吞咽功能可以通过食物或液体的类型（即刺激物）进行生理调节，但刺激物对双轴加速计信号的影响从未被彻底研究过。因此，本研究的目的是研究刺激物对双轴加速计信号特征的影响。从 17 名健康参与者中采集信号，让他们吞咽 4 种不同的刺激物：水、花蜜稠苹果汁、蜂蜜稠苹果汁和稀薄钡混悬液。研究了两种吞咽任务：离散吞咽和连续吞咽。在吞咽分段和预处理后，在时域和时频域中提取了多种特征。对每个特征和每个吞咽任务分别进行了 Friedman 检验。
离散任务中有 6 个特征和连续任务中有 5 个特征的刺激物效应具有统计学意义。对具有显著刺激效应的特征进行分析表明，随着食团黏度的增加，信号的变化揭示出更慢且更明显的吞咽模式。
我们得出结论，刺激物类型确实会影响双轴吞咽加速计信号的特定特征，这表明相关的临床筛查方案可能需要针对刺激物进行特异性调整。
