Schumann Andy, Suttkus Stefanie, Bär Karl-Jürgen
Lab for Autonomic Neuroscience, Imaging and Cognition (LANIC), Department of Psychosomatic Medicine and Psychotherapy, Jena University Hospital, 07740 Jena, Germany.
Sensors (Basel). 2021 Nov 18;21(22):7663. doi: 10.3390/s21227663.
Heart rate variability (HRV) is regularly assessed in neuroimaging studies as an indicator of autonomic, emotional or cognitive processes. In this study, we investigated the influence of a loud and cramped environment during magnetic resonance imaging (MRI) on resting HRV measures. We compared recordings during functional MRI sessions with recordings in our autonomic laboratory (LAB) in 101 healthy subjects. In the LAB, we recorded an electrocardiogram (ECG) and a photoplethysmogram (PPG) over 15 min. During resting state functional MRI, we acquired a PPG for 15 min. We assessed anxiety levels before the scanning in each subject. In 27 participants, we performed follow-up sessions to investigate a possible effect of habituation. We found a high intra-class correlation ranging between 0.775 and 0.996, indicating high consistency across conditions. We observed no systematic influence of the MRI environment on any HRV index when PPG signals were analyzed. However, SDNN and RMSSD were significantly higher when extracted from the PPG compared to the ECG. Although we found a significant correlation of anxiety and the decrease in HRV from LAB to MRI, a familiarization session did not change the HRV outcome. Our results suggest that psychological factors are less influential on the HRV outcome during MRI than the methodological choice of the cardiac signal to analyze.
心率变异性（HRV）在神经影像学研究中经常被评估，作为自主神经、情绪或认知过程的一个指标。在本研究中，我们调查了磁共振成像（MRI）期间嘈杂拥挤的环境对静息HRV测量值的影响。我们比较了101名健康受试者在功能MRI检查期间的记录与在我们的自主神经实验室（LAB）中的记录。在LAB中，我们记录了15分钟的心电图（ECG）和光电容积脉搏波描记图（PPG）。在静息态功能MRI期间，我们采集了15分钟的PPG。我们在每个受试者扫描前评估了焦虑水平。在27名参与者中，我们进行了随访检查以研究习惯化的可能影响。我们发现类内相关系数较高，在0.775至0.996之间，表明不同条件下具有高度一致性。当分析PPG信号时，我们未观察到MRI环境对任何HRV指标有系统性影响。然而，与ECG相比，从PPG中提取的SDNN和RMSSD显著更高。尽管我们发现焦虑与从LAB到MRI的HRV降低之间存在显著相关性，但熟悉过程并未改变HRV结果。我们的结果表明，在MRI期间，心理因素对HRV结果的影响小于用于分析的心脏信号的方法学选择。
