[How do pleasant and unpleasant odours change the breathing pattern?]
H Gudziol1, B Wajnert, G Förster
1Klinikum der Friedrich-Schiller-Universität, Klinik und Poliklinik für Hals-Nasen-Ohrenheilkunde, Lessingstrasse 2, 07740 Jena. hilmar.gudziol@med.uni-jena.de
Laryngo- Rhino- Otologie
|August 29, 2006
Summary
Pleasant odors (PEA) increased inhalation duration and depth, while unpleasant odors (H2S) shortened exhalation duration. Olfactory evoked respiratory responses (OERRs) occurred in all subjects, indicating odor perception influences breathing patterns.
Area of Science:
- Olfactory neuroscience
- Respiratory physiology
Background:
- Commonly believed that pleasant odors stimulate and unpleasant odors shorten breathing.
- Previous research has not sufficiently tested breathing responses to short, pure odor stimuli.
Purpose of the Study:
- To investigate the influence of short, pure odor stimuli on inhalation and exhalation.
- To determine if olfactory evoked respiratory responses (OERRs) are consistently elicited by both pleasant and unpleasant odors.
Main Methods:
- 53 subjects breathed through one nostril while respiratory pressure was measured in the other.
- Short (200 ms) stimuli of hydrogen sulfide (H2S, unpleasant) and phenylethylalcohol (PEA, pleasant) were presented.
- Olfactory evoked respiratory responses (OERRs) were defined as >20% change in respiratory parameters.
Main Results:
- PEA stimuli increased inhalation duration and depth (enlarged inhalatory curve area).
- H2S stimuli more frequently decreased exhalation duration and increased exhalation curve area.
- All subjects exhibited OERRs to at least one odor; 52 responded to both.
Conclusions:
- Repeated H2S and PEA stimuli consistently evoke OERRs in normosmic individuals.
- Stimulus intensity did not affect the OERR rate, suggesting perithreshold stimuli are optimal.
- Odor perception demonstrably influences respiratory behavior, impacting both inhalation and exhalation phases.
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