Abstract
In order to evaluate parasympathetic activation which causes driving errors, without placing any burden on the monitored individuals, we conducted a non-contact parasympathetic activation monitoring through the back of a chair using a compact 24-GHz microwave-radar. We measured the high-frequency (HF, 0.15–0.4 Hz) power spectrum of heart rate variability (HRV) which reflects parasympathetic activation, induced by a full stomach. All participants had a large all-you-can-eat meal with beverages for lunch within 20 min. Before and after the large meals for durations of 10 min, the non-contact measurement was conducted for seven healthy male volunteers (mean age: 23 ± 1-year-old). In both non-contact (microwave radar) and contact (ECG as a reference) measurement, HF shows similar variations before and after large meal. Large meal significantly (p < 0.05) increased non-contact-derived HF from 1,026 ± 510 to 1,893 ± 613 ms2 (922 ± 628 to 1,861 ± 940 ms2, p < 0.05). This technique allows parasympathetic activation monitoring for safety precautions.
This is a preview of subscription content, log in via an institution to check access.
References
Ikeda T, Abe A, Yusu S (2006) The full stomach test as a novel diagnostic technique for identifying patients at risk of Brugada syndrome. J Cardiovasc Electrophysiol 17:602–607
Kikuchi M, Ishihara M, Matsui T et al (2004) Biomedical engineering’s contribution to defending the homeland. IEEE Eng Med Biol Mag 23:175–186
Matsui T, Hagisawa K, Ishizuka T et al (2004) A novel method to prevent secondary exposure of medical and rescue personnel to toxic materials under biochemical hazard conditions using microwave radar and infrared thermography. IEEE Trans Biomed Eng 51:2184–2188
Michail E, Kokonozi A, Chouvarda I, Maglaveras N (2008) EEG and HRV markers of sleepiness and loss of control during car driving. Conf Proc IEEE Eng Med Biol Soc 256:6–2569
Osaka M, Murata H, Fuwamoto Y et al (2008) Application of heart rate variability analysis to electrocardiogram recorded outside the driver’s awareness from an automobile steering wheel. Circ J 72:1867–1873
Sato S, Taoda K, Kawamura M et al (2001) Heart rate variability during long truck driving work. J Hum Ergol (Tokyo) 30:235–240
Suzuki S, Matsui T, Imuta H et al (2008) A novel autonomic activation measurement method for stress monitoring: non-contact measurement of heart rate variability using a compact microwave radar. Med Biol Eng Comput 46:709–714
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Gotoh, S., Suzuki, S., Imuta, H. et al. Non-contact determination of parasympathetic activation induced by a full stomach using microwave radar. Med Biol Eng Comput 47, 1017–1019 (2009). https://doi.org/10.1007/s11517-009-0506-4
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11517-009-0506-4