The nasal bridge is the upper part of the nose, where the and surrounding provide structural support. While commonly discussed in human anatomy, nasal bridges exist in various forms across many , particularly . The shape, size, and function of the nasal bridge are influenced by evolutionary , playing a key role in respiration, sense of smell, and thermoregulation.
The height and shape of the nasal bridge vary among individuals and populations, reflecting genetic diversity and environmental . A high nasal bridge, often associated with a proportionally elongated nasal passage, is observed with greater frequency in populations indigenous to cold climates. This morphology is hypothesized to enhance the conditioning of inhaled air through increased surface area for heat and moisture exchange, which mitigates the physiological stress of frigid, desiccating atmospheric conditions. By contrast, a lower nasal bridge is more prevalent in populations originating from warm, humid environments, where airflow efficiency may be prioritized. However, this morphology is a polygenic trait shaped by complex genetic, developmental, and environmental factors, leading to substantial variation within and between populations.
The procerus muscle, a small pyramidal muscle in the glabella, creates horizontal wrinkles on the nasal bridge. It is involved in facial expressions such as and those associated with attentional control, and it indirectly helps shield the eyes from bright light. Because it contributes to wrinkle formation, it is often targeted in non-surgical facial rejuvenation treatments, such as botulinum toxin injections.
An appearance of a widened nasal bridge can be seen with dystopia canthorum, which is a lateral displacement of the inner canthus of the eyes. Dystopia canthorum is associated with Waardenburg syndrome.
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