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Published on: August 24, 2017
Effects of parametric speaker sound on physiological functions during mental task
Soomin Lee1, Tetsuo Katsuura, Yoshihiro Shimomura
1Graduate School of Engineering, Chiba University, Chiba, Japan. yisoomin@restaff.chiba-u.jp
Journal of Physiological Anthropology
|February 11, 2011
Summary
Parametric speakers appear safer for the human body than general speakers, showing lower physiological burden. This study found reduced sympathetic nervous activity and improved reaction times with parametric speaker use.
Area of Science:
- Biomedical Engineering
- Human Physiology
- Acoustics
Background:
- Parametric speakers are increasingly used in various applications.
- The safety of parametric speakers concerning human physiological responses remains largely uninvestigated.
Purpose of the Study:
- To evaluate the physiological effects of parametric speakers compared to general speakers.
- To assess the impact on cardiovascular and nervous system functions.
Main Methods:
- Nine male subjects underwent three sessions: baseline, a 45-min mental task with either a general or parametric speaker, and recovery.
- Physiological parameters including ECG, PTG, EEG, BP, and BRS were measured.
- Two-way repeated measures ANOVA was used to analyze the data.
Main Results:
- Parametric speakers resulted in significantly lower sympathetic nervous activity and second derivative of PTG during task and recovery periods compared to general speakers.
- A trend towards smaller changes in parasympathetic nervous activity was observed with parametric speakers.
- Reaction time was shorter when using a parametric speaker.
Conclusions:
- Parametric speakers impose a lower physiological burden, particularly on the cardiovascular system, compared to general speakers.
- The findings suggest parametric speakers may be a safer auditory technology for human exposure.
