Gu Zifan, Zarubin Vanessa C, Mickley Steinmetz Katherine R, Martsberger Carolyn
Department of Physics, Wofford College, Spartanburg, SC, United States.
Department of Biomedical Informatics, Harvard Medical School, Boston, MA, United States.
Front Physiol. 2022 Jun 13;13:897284. doi: 10.3389/fphys.2022.897284. eCollection 2022.
Heart Rate Variability (HRV) can be a useful metric to capture meaningful information about heart function. One of the non-linear indices used to analyze HRV, Detrended Fluctuation Analysis (DFA), finds short and long-term correlations in RR intervals to capture quantitative information about variability. This study focuses on the impact of visual and mental stimulation on HRV as expressed DFA within healthy adults. Visual stimulation can activate the automatic nervous system to directly impact physiological behavior such as heart rate. In this investigation of HRV, 70 participants (21 males) viewed images on a screen followed by a math and recall task. Each viewing segment lasted 2 min and 18 s. The math and memory recall task segment lasted 4 min total. This process was repeated 9 times during which the participants' electrocardiogram was recorded. 37 participants (12 males) opted in for an additional 24-h Holter recording after the viewing and task segments of the study were complete. Participants were randomly assigned to either a pure (organized image presentation) or mixed (random image presentation) image regime for the viewing portion of the study to investigate the impact of the external environment on HRV. DFA 1 was extracted from the RR intervals. Our findings suggest that DFA 1 can differentiate between the viewing [DFA 1 range from 0.96 (SD = 0.25) to 1.08 (SD = 0.22)] and the task segments [DFA 1 range from 1.17 (SD = 0.21) to 1.26 (SD = 0.25)], < 0.0006 for all comparisons. However, DFA 1 was not able to distinguish between the two image regimes. During the 24-hour follow up, participants had an average DFA 1 = 1.09 (SD = 0.14). In conclusion, our findings suggest a graded response in DFA during short term stimulation and a responsiveness in participants to adjust physiologically to their external environment expressed through the DFA exponent.
心率变异性（HRV）可以作为一种有用的指标，用于获取有关心脏功能的有意义信息。去趋势波动分析（DFA）是用于分析HRV的非线性指标之一，它通过RR间期来发现短期和长期相关性，以获取有关变异性的定量信息。本研究聚焦于视觉和心理刺激对健康成年人HRV的影响，这种影响通过DFA来体现。视觉刺激可激活自主神经系统，直接影响诸如心率等生理行为。在这项关于HRV的研究中，70名参与者（21名男性）在屏幕上观看图像，随后进行数学和回忆任务。每个观看片段持续2分18秒。数学和记忆回忆任务片段总共持续4分钟。这个过程重复9次，期间记录参与者的心电图。37名参与者（12名男性）在研究的观看和任务片段完成后，选择进行额外的24小时动态心电图记录。在研究的观看部分，参与者被随机分配到纯（有组织的图像呈现）或混合（随机图像呈现）图像模式，以研究外部环境对HRV的影响。从RR间期提取DFA 1。我们的研究结果表明，DFA 1能够区分观看阶段[DFA 1范围为0.96（标准差 = 0.25）至1.08（标准差 = 0.22）]和任务阶段[DFA 1范围为1.17（标准差 = 0.21）至1.26（标准差 = 0.25）]，所有比较的P < 0.0006。然而，DFA 1无法区分两种图像模式。在24小时随访期间，参与者的平均DFA 1 = 1.09（标准差 = 0.14）。总之，我们的研究结果表明，在短期刺激期间DFA存在分级反应，并且参与者具有通过DFA指数在生理上适应外部环境的反应能力。
