The near-universal adoption of neural interface implants in GLMZ — approximately 78% of Tier-1 through Tier-3 residents carry some form of cortical uplink by adulthood — has generated an elaborate, largely informal system of social etiquette governing their use. These norms are not codified in law but are enforced through social pressure, professional consequence, and in some communities, outright ostracism. The central tension animating all neural etiquette is the question of presence: when a person's attention can be split between the physical room and an invisible digital overlay, what counts as being there?

The practice of 'going dark' — voluntarily suspending one's neural overlay during a conversation or meal — has become the dominant signal of respect and intimacy in mid-to-upper tier social contexts. In corporate dining culture along the Meridian Gold Corridor, requesting a dark table at a restaurant like Sable & Ferrite or the Lakeview Canteen signals both social confidence and the implicit promise of undivided attention. Some establishments enforce darkness architecturally, using signal-dampening wallpaper printed with conductive mesh that suppresses interface activity within specific dining rooms. These rooms command premium pricing and are booked weeks in advance. The ability to go dark, and to do so willingly, is itself a status marker.

Conversely, in the lower tiers where neural interfaces are older, cheaper, and often partially malfunctioning, etiquette around overlay use is less rigidly policed. In the dense residential corridors of the Wacker Stack and the Pilsen Mezzanine, it is entirely normal to hold a conversation while visibly tracking something in overlay — the slight upward eye-movement and verbal latency that signals divided attention is so common it has its own slang: being 'half-here.' Children raised in these environments develop a facility for reading half-here interlocutors that upper-tier residents often find uncanny. They learn to interpret micro-pauses and gaze drift as part of normal conversational rhythm rather than rudeness.

The emergence of shared overlay spaces — collaborative augmented environments where multiple users can co-inhabit a digital layer superimposed on physical space — has introduced new etiquette challenges around consent and intrusion. Dropping an unsolicited overlay object into someone's visual field, called 'tagging their room,' is considered aggressive and sexually harassing depending on the content. Corporate HR departments now maintain Interface Conduct Officers, a role that did not exist fifteen years ago. The Meridian Etiquette Institute, a private consultancy headquartered in the Streeterville Corporate Quarter, publishes a quarterly update to its Neural Conduct Framework, a document that is simultaneously mocked as pretentious and quietly consulted by anyone seeking upward mobility.

For the approximately 22% of residents who are unimplanted — whether by choice, poverty, medical contraindication, or religious objection — navigating a world designed around neural interface norms is a daily exercise in exclusion. Restaurants that enforce darkness policies inadvertently privilege the implanted, since going dark requires having something to turn off. Unimplanted residents in professional contexts sometimes wear blank-screen haptic wristbands that mimic the visual cues of an active interface, a practice called 'faking the blink' that carries both practical utility and considerable social shame.