Intersecting Minds

The Loop of Emotion

by Jeah Kim

A neuroanatomical illustration titled “The Loop of Emotion” that visually explains the bidirectional relationship between facial expressions and emotional processing in the brain—also known as the Facial Feedback Hypothesis. The core concept is that facial expressions can influence emotional states via neural feedback loops. The background is a muted light blue, evoking a calm atmosphere. The overall tone of the illustration is soft and slightly dreamy, balancing scientific precision with emotional warmth. Gentle gradients, translucent overlays and active 3D arrows create a sense of flow between the anatomical structures and the brain’s emotional centers, reinforcing the idea of an interconnected loop. The use of pastel hues—peach-toned brain structures, light yellow nerve branches, soft purples and yellows for emotional markers—and subtle lighting adds to the delicate, human-centered feel. The illustration is organized into three main sections: Figure 1. Left Section (Facial Musculature and Innervation overlaid on a portrait in three-quarter view): A partially transparent female face reveals the underlying facial muscles and trigeminal nerve innervation zones. Labeled muscles are marked with color-coded dots at the end of leader lines, representing: ● Smiling muscles (yellow) ● Frowning muscles (purple) Labeled muscles include: ● Corrugator supercilii (frowning; purple dot) ● Levator labii superioris (smiling; yellow dot) ● Zygomaticus major (smiling; yellow dot) ● Risorius (smiling; yellow dot) Three color-coded trigeminal nerve branch innervation zones are also shown: ● Ophthalmic (V1): uppermost branch (light pink) ● Maxillary (V2): middle branch (green) ● Mandibular (V3): lowermost branch (magenta) Figure 2. Center Section (Same portrait with bone and brain structures overlaid): A semi-transparent overlay integrates the facial anatomy with cranial bone, trigeminal nerve pathways, and brain structures. This section illustrates how the proprioceptive fibers of the trigeminal nerve transmit signals from the face to the brain. * Caption for Figure1-2: Muscle activity is sensed through proprioceptive fibers of the trigeminal nerve. Figure 3. Right section (Neural Pathway in the Brain): A zoomed in cross-section of the brain maps the emotional processing pathway: * Caption for Figure3: (1) Signals from facial muscles travel to the trigeminal nucleus, which serves as a hub. (2) Then the signals are sent to emotion-processing centers, including the amygdala, locus coeruleus, and pulvinar thalamus. (3) The sensory input reaches the prefrontal cortex, which is responsible for interpreting and regulating emotions. This circuit helps the brain link facial expressions, creating a feedback loop that reinforces emotional understanding and response.

Artist Statement

This illustration explores the unseen dialogue between facial muscles and emotional experience. Inspired by research on how Botox affects not only facial movement but also emotion, the piece visualizes the Facial Feedback Hypothesis—the idea that our expressions are not just outward reflections of inner states but active participants in shaping them.

The brain doesn’t simply observe a smile or a furrowed brow; it senses muscle activity via proprioceptive fibers of the trigeminal nerve, interpreting these signals as emotional cues. From there, a cascade of neural communication unfolds: messages pass through the trigeminal nucleus to emotion-processing centers such as the amygdala, locus coeruleus, and pulvinar thalamus, eventually reaching the prefrontal cortex, where emotions are interpreted and regulated.

By revealing this hidden circuit, the piece makes visible how relaxing the glabellar region can ease stress or how the simple act of smiling can evoke joy—tiny movements with profound emotional consequences. This piece invites viewers not only to be informed but also to be uplifted—perhaps even to smile and feel a gentle sense of calm as they engage with it.

Artist Bio

Jeah Kim is a second-year graduate student in the Biomedical Communications program at the University of Toronto. With experience creating anatomical 3D models for surgical simulation and patient education at a medical center, she bridges science and storytelling through visual media. Her work spans journal figures, animations, and interactive XR experiences, all driven by a passion for making complex science accessible and engaging. As a biomedical communicator, Jeah strives to spotlight novel scientific discoveries and inspire curiosity. She is also deeply interested in enhancing medical services through creative visual strategies.

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