Humans without a sense of smell breathe differently

Area of Science:

• Neuroscience
• Respiratory Physiology

Background:

• Olfaction, the sense of smell, has a limited perceived role in human behavior.
• However, anosmia (the absence of smell) is linked to significant negative health outcomes, including reduced lifespan.
• The nose is crucial for both olfaction and respiration, with breathing patterns influenced by odors.

Purpose of the Study:

• To investigate if nasal respiratory airflow patterns are altered in individuals with isolated congenital anosmia.
• To explore the potential impact of these altered airflow patterns on the deleterious outcomes associated with anosmia.

Main Methods:

• Utilized a wearable device to record nasal airflow for 24-hour periods.
• Compared respiratory nasal airflow patterns in participants with congenital anosmia and healthy controls during both wakefulness and sleep.

Main Results:

• Significantly altered patterns of respiratory nasal airflow were observed in individuals with anosmia compared to controls.
• The distinct respiratory traces enabled the classification of anosmia with 83% accuracy.
• These findings suggest a link between altered nasal airflow and health, emotion, and cognition.

Conclusions:

• Altered respiratory nasal airflow patterns are a notable characteristic of anosmia.
• A portion of the negative health consequences attributed to anosmia may stem from these respiratory changes, rather than solely from the loss of smell perception.