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The significant impact of environmental noise on cardiovascular health is becoming more widely recognized. However, detailed studies related to environmental noise and human physiology are very limited. This study provides a detailed evaluation of heart rate and respiratory responses to different noise levels in a controlled experimental environment using Doppler radar. The findings indicate that while respiratory rates show notable variations, heart rates remain largely unchanged with alterations in noise levels. This non-invasive approach to assessing the effects of environmental noise using Doppler radar could help improve indoor environmental quality by adapting conditions to enhance acoustic comfort and reduce stress for occupants.
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Heart rate and startle responses in diving, captive harbour porpoises ( Phocoena phocoena ) exposed to transient noise and sonar
ABSTRACT Anthropogenic noise can alter marine mammal behaviour and physiology, but little is known about cetacean cardiovascular responses to exposures, despite evidence that acoustic stressors, such as naval sonars, may lead to decompression sickness. Here, we measured heart rate and movements of two trained harbour porpoises during controlled exposure to 6–9 kHz sonar-like sweeps and 40 kHz peak-frequency noise pulses, designed to evoke acoustic startle responses. The porpoises initially responded to the sonar sweep with intensified bradycardia despite unaltered behaviour/movement, but habituated rapidly to the stimuli. In contrast, 40 kHz noise pulses consistently evoked rapid muscle flinches (indicative of startles), but no behavioural or heart rate changes. We conclude that the autonomous startle response appears decoupled from, or overridden by, cardiac regulation in diving porpoises, whereas certain novel stimuli may motivate oxygen-conserving cardiovascular measures. Such responses to sound exposure may contribute to gas mismanagement for deeper-diving cetaceans.
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- Award ID(s):
- 1159123
- PAR ID:
- 10278953
- Date Published:
- Journal Name:
- Biology Open
- Volume:
- 10
- Issue:
- 6
- ISSN:
- 2046-6390
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1242/bio.058679
