Why the Digital World Has No Smell
Walk into any mall and the sensory assault begins before you reach the storefronts. Retailers pump carefully crafted fragrances through their spaces to shape how you perceive their products. Hotels and theme parks do the same, creating invisible signatures that guests absorb without conscious notice.
The physical world has been doing this for decades. The digital one hasn’t. We spend more time reading, working, shopping and relaxing on screens — yet every website, app and virtual environment of our daily lives carries precisely the same odor density: zero.
Smell has a documented and outsized grip on memory. The “Proust Effect” — the involuntary warm recollection that a fragrance can trigger — is strong enough that a single whiff of something familiar can pull back detailed memories that the conscious mind has long archived. Individuals can “make the eyes remember”, as architect Juhani Pallasmaa observed, meaning that identification and emotional assessment of an environment depend heavily on what the nose reports.
That dependence extends beyond individual recollections. Terms like “Smellscape” (coined by geographer J. Douglas Porteous) describe how the aggregate of odors in a place drives our attitude toward it and informs our memory later. If people avoid aesthetically fine locations or dishes when the smell is wrong, scent is not merely an atmospheric garnish. It is arguably a primary channel for emotional appraisal.
The Scent-as-Brand Playbook
This is why scent has become a standard component of physical-space branding. Luxury marques use custom “scent identities” in dealerships to reinforce their emotional positioning — one unusual example being a spec-created car fragrance built on nutty coffee, dark leather and resinous amber notes meant to underline a message of self-expressive luxury. Retailers likewise lean on characteristic signatures that reach partons well before they step near the architecture. Such efforts work in part because the absence of a particular associative odor makes certain business models flat.
Amusement parks such as Disney put this in systematic operation with scent-emitting “Smellitzers”: patented odor-dispensing units synchronized with each ride and given a specific scent profile — burning wood for one ride, orange-and-pine notes for another. These deliberately target visceral recollection more than conscious memory, pushing the guest to connect the feeling of the experience with the smell without needing to realize that both stimuli occurred.
The Brain Opens a Second Interface
Precisely because scent is channeled to memory and limbic structures more directly than vision or hearing, it can alter emotional assessment, attention, desire, wellbeing and connection. Yet most interfaces still address only eyes and ears. Even peripheral sensory channels such as haptics have made their way into commercial products, while the olfactory channel has essentially not arrived.
What would have to happen for smell to become addressable in typical device interaction? Like any other output medium, it would require integrated, controllable hardware suited to the user's environment; a way of producing variation that allows for specific fragrances per context; a software stack to determine time and intensity; and, above all, a proper set of design patterns, so we don't get trapped between arbitrary sensory gimmicks and aesthetically pleasing use of scent.
However subtle, design presence of scent is an opportunity to have machines meaningfully affect the limbic system — for attention, memory, or just humane context. Without addressing this channel, the next era of interface design is likely to stay within these existing handles. The nose remains the most direct of the interfaces that we have still refused to code.
When Fragrance Entertainment Fizzled
Huxley's disdain for cinema in “Silence is Golden” (1912) proved prescient, and his fictional Brave New World (1932) imagined a future where multisensory amusements, complete with a “scent organ” performing a Herbal Capriccio of thyme and lavender, condition society into passive consumption. The entertainment industry of the 1950s chased that vision with experiments in colored film and 3D, culminating in two scented features in 1960: Scent of Mystery with Smell–O–Vision, which piped odors through tubes to each seat, and Behind the Great Wall with AromaRama, which pushed scents through the theater's ventilation system.
Critics and audiences rejected both. A New York Times review noted that synthetic smells “occasionally befit what one is viewing, but more often they confuse the atmosphere.” Complaints ranged from oversubtle to overpowering odors, compounded by equipment that disrupted the show. The technologies vanished quickly, but their failure teaches a lasting lesson about olfactory UX.
Why the Nose Said No
The verdict was not purely a hardware problem. AromaRama's ventilation-based diffusion lagged behind the action and left lingering scents between scenes, which certainly did not help. Yet three deeper factors explain why odors did not land:
- Digital entertainment is conventionally odorless. Audiences do not expect smells at a movie, and their brains filter them out — a phenomenon researchers call “inattentional anosmia.”
- Background smells fade or annoy. A brief orange scent as a character slices the fruit in Behind the Great Wall was “impressive,” per the critics. But an odor left to linger, however pleasant, turns into an irritant.
- Cinema asks for passive perception. Immersion depends on the suspension of disbelief. Viewers sitting still while sight and hearing interpret the story can have that state shattered by a scent that feels irrelevant or poorly timed.
For scented film to work, olfactory cues must be woven into the narrative and delivered discreetly, smoothly, and with perfect timing. Until then, the format lives on mainly in auteur experiments and 4D-theater booths.
Interactive Scent: Gaming and VR
Video games, unlike movies, expect active engagement. The player helps shape the story, so demands for realism run higher. That context makes fragrance a more natural addition, and virtual reality is the current frontier for full sensory stimulation.
Beyond headsets, haptic gloves from Meta and Manus already simulate touch, and Teslasuit's full-body garment captures motion and biometry while delivering haptic feedback and temperature emulation. Scent delivery is arriving more slowly, but a few products exist. GameScent sells a cube that uses AI to distribute up to eight odors — from “gunfire” and “explosion” to “forest” and “storm” — synced to in-game events.
Most experimentation happens in academic labs. Researchers have assigned specific scents to locations within a VR game and diffused them as players move, while others have tested hand-held devices that let participants “smell” objects on demand. The evidence consistently points one way: fragrance deepens immersion and boosts perceived realism in both virtual and traditional gaming environments.
A strong example from traditional gaming is “Tainted” (2017), designed around the South-East Asian legend of Pontianak, a vengeful spirit believed to hide in banana trees. Players must locate and burn those trees to progress. A scent module in front of the player releases banana odor when the ghost is near and pineapple aroma when a needed flammable object is in reach. Smells thus carry functional weight: they warn, guide, and become as integral to play as visuals or audio.
That integration works far better than a passive ambient perfume. Scent gains value when it is interactive — when it responds to the user's choices and delivers information the other senses cannot.
Olfactory Learning Aids
Associating facts with smells is an ancient memory strategy that the digital age is finally harnessing. In physical spaces, oil-infused classrooms show improved cognition in students. Scented books and toys enrich children's play, offices pump fragrance through diffusers to raise productivity, and the Jorvik Viking Centre has made its signature “smells of Viking-age York” a core part of a historically immersive visit. These installations are memorable precisely because the olfactory channel reinforces a story rather than merely decorating it.
As education moves online, scent devices are being positioned less as replacements for textbooks than as “learning supplements.” Teachers have access to diffusers that release peppermint to sharpen students' attention, and large units for whole facilities are available commercially. The research extends to sleep: studies suggest that exposure to scents during rest solidifies newly learned material and improves cognitive function. MIT researchers have even built and tested a wearable scent-emitting device that triggers targeted memory reactivation.
These developments anticipate smart-home devices that integrate fragrance into daily routines for productivity, mood support, and even early detection of cognitive decline via changes in smell perception. Still, lessons from the cinema laboratories apply: scent will earn its place not as an ambient gimmick but as an information channel that is meaningful, timely, and — where possible — under the user's control.
Why Scent Design Keeps Falling Short
Our understanding of smell has a surprisingly short history. It wasn't until Richard Axel and Linda Buck won the Nobel Prize in 2004 for identifying the genes that control odor receptors that we learned how the body processes scents. Even now, we only have a partial picture, perhaps summarized best by three key takeaways:
- Smells trigger deep, personal memories and emotions. While any scent can evoke a memory, the specific connection depends entirely on the individual. One person's comforting institutional soap might be another's reminder of an unpleasant past.
- Unpleasant scents stick around. Both literally and psychologically, bad smells linger longer and have a stronger effect on our mental state and memory than pleasant ones.
- Context is everything. A nice aroma ruined by an out-of-place delivery method is worse than no smell at all.
Knowing this, we can derive a few core principles for anyone attempting to build a scent-enabled experience.
Keep Users In Control
Because the response to a specific fragrance is so individual, as design researcher J. Douglas Porteous noted in his work on "smellscapes," scent experiences must be personalized. The smell of a certain spice shop might bring one person joy and trigger a painful memory for another. A practical system must let each user select, filter, or manage the scents they encounter to avoid creating a negative association with the product or the activity.
The Jasmine device is a good example of this principle, creating a unique VR experience by allowing users to smell the forest at various stages of mindfulness.
Simplicity Over Novelty
There’s an old problem in scent design: we lack a universal language to describe or classify smells. While some languages, like Jahai in Malaysia, have specific words for complex odors, English usually falls back on comparisons like "smells like orange." Aristotle tried classifying scents into six groups, Linnaeus expanded it to seven, and Hans Henning created a scent prism, but all these systems fail to recreate anything beyond the simplest scents.
Comprehensive lists like the Odor Character Profiling chart do exist, containing 146 unique descriptors, and they help. However, building a device that can produce distinct, sophisticated scents like "the warm touch of an early summer sun" is expensive and risky. Since getting it wrong has a strong negative effect, the better path is to prioritize reproducing a small set of simple, widely pleasant smells well, accepting that trade-off in experience.
Delivery Matters More Than The Scent
History has proven that bad delivery ruins everything. Disney’s Smellitzers worked because the diffusers were hidden, the scents felt contextual, and they didn't overwhelm you. In contrast, "smell-o-vision" movies in the 1950s crashed because of the clunky delivery systems, which even included treatments that, according to critics, left the air with a sticky, sweet, and upsetting residue between scenes.
Successful examples today don't complicate the core experience. The eScent mask, for instance, is a simple FFP3 mask with a slot for an essential oil-infused applicator. It lets the user choose the scent and can swap it out easily, but otherwise, putting it on feels exactly like any other mask. It requires no extra setup, no equipment, and doesn't draw attention to the smell itself.
Drifting Toward A Digital Sense Of Smell
We may have fumbled scent technology in the past, but recent progress suggests we are learning from those mistakes. Alex Wiltschko, a former Google researcher, founded Osmo in 2022 to literally give computers a sense of smell. The company isn’t just trying to digitize existing odors; they are experimenting with using AI to analyze molecular structures or evaluate a machine's descriptions.
One figure that has emerged from these tests is a 53% accuracy rate. While that number isn't meant to be a complete validation, it does prove that basic data collection is being improved upon and incorporated into future workshops that imagine a connected scent-augmented world.
If research like this eventually slows down (and actually moves to practical device manufacture), the entire ballgame changes for digital UX. For designers, this represents an open frontier. How can a specific scent be packed into a virtual learning module?
This is precisely where craft is necessary to enrich the training. Smells hold the potential to transform education and health industries, but to harness that power, they must be designed with precision of intensity and contextual relevance. Overloading the sense is the fastest way to ruin an immersive experience, reintroducing old failures. In that future, a well-placed, subtle scent can attach itself to a lesson, letting the user mentally time-travel when they experience it next.
