The nose often appears to move, twitch, or subtly flare when a person speaks. This slight movement of the nostrils and the nasal tip is a normal anatomical occurrence, reflecting the coordination between the structures of the nose and the complex mechanics of speech production. The appearance of the nose shifting is a visual byproduct of surrounding facial muscles activating to control airflow and shape sounds. Understanding this movement requires looking at the specific muscles involved and the physiological need for their activation during articulation.
The Muscles Responsible for Nasal Movement
The visible movement of the nose during speech is primarily controlled by a small group of facial muscles. These muscles are part of the larger network responsible for facial expressions and are innervated by the facial nerve (cranial nerve VII). The largest of these is the Nasalis muscle, which has two distinct parts that manipulate the nasal cartilages.
The transverse part of the Nasalis muscle, also called the compressor naris, originates on the maxilla and extends across the bridge of the nose. When this section contracts, it compresses the nasal aperture, narrowing the nostrils. The alar part of the Nasalis, known as the dilator naris, also arises from the maxilla and inserts into the alar cartilage. This action pulls the nose tissue downward and outward, which widens or flares the nostrils.
Another important contributor is the Depressor Septi Nasi muscle, a small muscle that connects the maxilla to the nasal septum. Its contraction pulls the nasal septum and the tip of the nose downward. This downward motion assists the alar part of the Nasalis in widening the nostrils by stretching the membranous septum. These three components work in concert to create subtle, observable changes in nasal shape and positioning.
The Physiological Link Between Speech and Nasal Motion
The activation of these nasal muscles is rooted in the body’s need to precisely regulate airflow for sound production. Speech involves a continuous, coordinated flow of air from the lungs that must be shaped and directed. Subtle nasal adjustments manage the balance between oral and nasal airflow, which is important when articulating specific types of sounds.
The most direct link occurs during the production of nasal consonants, such as /m/, /n/, and /ng/. For these sounds, the velum (soft palate) lowers to open the velopharyngeal passage, allowing air and sound to resonate through the nasal cavity. The small movements of the Nasalis and Depressor Septi Nasi muscles may accompany this process, helping to optimize the size of the nasal aperture for acoustic requirements. The motor cortex coordinates this sequence, linking the movement of the tongue, lips, jaw, and nasal structures into a seamless articulation plan.
The muscles responsible for nasal movement are intertwined with the muscles used for articulation in the mouth. The Nasalis and Depressor Septi Nasi muscles are part of the broader superficial musculoaponeurotic system of the face. When a person speaks, the muscles that move the lips and cheeks for forming vowels and oral consonants are activated. This activation can synergistically cause a simultaneous, slight pull on the nasal structures, making the nose movement a secondary, coordinated action that ensures clear and expressive speech.
Factors Influencing the Degree of Nasal Movement
Variation in nasal movement is influenced by anatomical and behavioral factors. Genetic predisposition plays a role, as the size, strength, and attachment points of the nasal muscles differ significantly between individuals. People with more prominent or robust Nasalis and Depressor Septi Nasi muscles will exhibit a more pronounced visual effect when they contract.
Speech habits and personal speaking styles also contribute to the degree of movement. Individuals who speak with greater projection, emphasis, or an energetic style recruit more muscle activation throughout the face, including the nasal region. Emphatic speech or regional accents involving a stronger oral component may result in a more vigorous, coordinated movement of the lower facial muscles, making the nose appear to move more.
Emotional expression is another major influence, since the nasal muscles are primarily muscles of facial expression. Strong emotions such as anger, excitement, or deep concentration often trigger greater involuntary activation of the alar part of the Nasalis muscle to flare the nostrils. When speaking during heightened emotional states, this increased nasal muscle tension integrates into the speech pattern, resulting in a momentarily more dramatic movement of the nose than in neutral conversation.