Ambient Signifiers
How I Learned to Stop Getting Lost and Love Tokyo Rail
by Ross Howard on 2006/09/19 | [16 Comments]
“Although subtle, this technique has a noticeable impact on assisting passengers to their destinations and so increases efficiencies in the rail network.”
One task we face on a day-to-day basis is how to effectively communicate ever-increasing amounts of information within increasingly richer and more complex web contexts. While living in Japan, I discovered an approach used as part of the way-finding system of Tokyo’s rail network that has a number of interesting implications for user interface design.
Tokyo’s rail system is famous for being the most complicated and bewildering in the world. With over 1,000 stations, even locals get lost and disoriented. As a designer, I try to be aware of attempts at systems and methods of communication. While traveling the Tokyo rail lines, I quickly realized that apart from the obvious use of real-time electronic signage, colored trains, and audio announcements, there were also other techniques being used to assist travelers in knowing where they were, and where they were going. These techniques were subtler, and bordered on subliminal; this was what really interested me.
When on my regular commute on Japan Railways (JR) East’s Chuo-Sobu line out from the town center to the outer suburbs where I lived, I noticed that short, simple chime melodies sounded on each platform as the train was waiting for passengers to get on and off. I noticed that these melodies were different for each station (indeed, Miyama station, which disembarks to Tokyo Disneyland, plays the theme to “It’s A Small World After All“).
Of course, some of the trips on this network are irregular and spontaneous, and in those situations, the melodies are merely signals for when a train has stopped at the station. However, for the majority of JR East’s 20 million daily users, trips tend to be end-to-end commutes between their home and work, sometimes involving as many as three transfers. Because it is not uncommon for these trips to take over an hour, passengers tend to pass the time by reading small pocket novels, playing with their portable gaming systems, or furiously programming their cellphones. Coupled with these distractions, Tokyo seen from a train, is monotonous and indistinct, so establishing one’s location visually must be an active exercise.
To daily commuters, the station melodies augment the existing ambient landscape (going through tunnels, turning corners, large landmarks, etc.), so despite not necessarily paying attention to the visual cues around them, travelers subconsciously start building up a “landscape” of their journey based on these audible inputs. They quickly learn the melody of their final destination terminal (it is played incessantly as they wait on the platform for their return journey), and soon recognize the melody of the terminal that precedes theirs. After long-term use of the same route, commuters build up a unique chain of melodies that accompany them on their way home. Without necessarily realizing why, they begin to establish a familiarity with these sounds, and can quickly discover when they have overshot their destination by hearing an unfamiliar melody that indicates a strange place.
I call these cues ambient signifiers: design elements that communicate subtly as part of the environment’s ambiance. Although subtle, this technique has a noticeable impact on assisting passengers to their destinations and so increases efficiencies in the rail network. When dealing with such large congestion and complexity, any efficiency improvements will have massive benefits for both the rail infrastructure and Tokyo itself.
The reason for discussing this is not to demonstrate how amazing the Tokyo rail network is (it is!), but to learn from this approach. We can draw parallels between transport networks and their passengers, and websites and their users: both can be complex structures; both have navigable routes and destinations; and both can involve large groups of people using routes with the aid of wayfinding tools. Both also involve users dealing with a sensory overload of sounds, distractions, visual noise, and time constraints. For large-scale websites, the number of users may even be similar to large transport networks, and any efficiency improvement can have a positive impact on both user experience and overheads such as bandwidth and server load. This approach also has business benefits: users will make fewer mistakes; there will be fewer customer support issues; and fewer repair and maintenance.
There are differences between the two concepts that are subtler, however, and arguably more important. When dealing with transport, not all passengers are taking one journey with a common source and destination. Instead, they are constantly getting on and off routes to complete their own unique journeys. With websites, there are usually established paths that tend to have beginning and end points with little need to end the process at certain points along the way. Websites can also provide other important levels of information that transport networks don’t. Websites may need to demonstrate, for example, a change in status, a change in content, or a change in context. They may want to encourage a user to pause on a certain page or to bypass another. They may need to demonstrate progress or to signify an alert. The obvious way to do these things has been to use overt (high-frequency) signifiers, such as iconography and language. What I’ve learned from Tokyo, however, leads me to believe that using ambient (low-frequency) signifiers may be another important—and sometimes more successful—approach.
Web users are already being exposed to emerging rudimentary implementations of ambient signifiers. For example, if you visit a secure site in Mozilla Firefox, you will see the location field in the navigation bar turn yellow. In another case, the BBC’s 2002 redesign of its bbc.co.uk website introduced the wonderfully elegant idea of “digital patina” (sometimes referred to as “digital color footprint”), in which usage patterns create worn paths (e.g., the more you visit the BBC Sports section, the darker the Sports box on the homepage becomes).
Having a user be able to gauge status or context without having to actively seek it out is surely one of the holy grails of human computer interaction. The examples above demonstrate how ambient signifiers fall into Steve Krug’s “Don’t Make Me Think” category of interface cues: they can make a website intrinsically more user-friendly without the user necessarily needing to understand how or why.
Using some common scenarios, we can explore how ambient signifiers can offer a new implicit level of communication—implicit in that they are not designed to be relied upon without prior knowledge (such as breadcrumbs, core navigation, and headings), but rather to indicate context, status, and location through suggestive cues that may be only be received subconsciously and enhanced through experience.
One obvious signifier is the use of change of status. Change in status may be an indication of whether a user is logged in or not, whether he or she is in a mode such as an editing mode or workflow situation, or is interacting with a secure page. For these situations, we would typically employ overt signifiers such as text saying “you are logged in” or perhaps a padlock icon. But these “on” or “off” indicators can also be implied through the use of ambient visual cues: the background color of the page can be changed to a darker hue or become subtly textured. With experience, these subtle cues will allow users to “feel” when they are logged in or when they are using a secure page. Without these cues, they will feel uncertain and will check the standard high-frequency interface elements for verification, such as the text that says “You are currently logged in.” As such, ambient signifiers can promote sensitivity and awareness, which in turn makes the user more responsive and responsible. The user may double-check whether she is in fact logged into a secure page before submitting her details because she senses something is not quite right.
How about content for different user types? Take for example a website that offers different pages for different countries. If a user enters a low-level page through a direct link (from a search engine, for example), the design could communicate to him that he is looking at a page with country-specific content such as prices and specifications, without having him search the page for clues as to what currency the prices are in and that the shipping cost to their country has been taken into account. This could be done using ambient signifiers by introducing minor palette variations for each territory or even country-specific imagery.
Imagine a site that has a complex dashboard widget or a page that presents an overview of the steps and information required for the multi-paged form that follows. How could the design help the user to focus on the page, make it a page that invites contemplation? Perhaps the page could show a contemplative image across the top of the page, encourage users to pause and muse over it. (Is this perhaps the idea behind Window XP’s “Bliss” wallpaper?)
How about implying age or expiration? An online publication could feature this month’s articles in high-contrast colors, while previous months are rendered more subtly. Auction sites could display expired auctions devoid of any color, whereas current auctions are highly saturated. Once an auction has met its reserve, an ambient signifier of color could change from yellow to red.
In cases like those presented above, current web designs tend to communicate using overt signifiers such as icons and text. These small, high-frequency elements—much like the signage at Tokyo stations—require active seeking on the user’s part. Ambient signifiers, on the other hand, are more constant and low-frequency in nature, working on a more passive and subconscious level without any effort from the user. Because of their low frequency, they can communicate effectively irrespective of the competing high frequency “sensory noise” present in today’s rich and complex web interfaces. Users don’t have to look anywhere—ambient signifiers are felt everywhere.
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Readers' Comments (16)
Gagan Diesh
8 Reputation points
Posted 2006/09/20 @ 08:33AM with
Hi Ross:
As I mentioned before, great article. Not sure about the value of the XP Bliss wallpaper but heck, I will choose to ignore that reference! ;)
I suggest a visit to an oldie but still interesting site reference: http://isseymiyake.com (click on autumn-winter 2002-2003). While the site is totally not usable for corporate structures, it is interesting for how they have used the glowing circle to mean navigation quite consistently…the audio cues are also consistent and set up expectations from the first screen where you choose men/women.
also interesting is the “map” and how it orients the user to a breadcrumb of where they have already been.
combine “ambient signifiers” with pavlovian conditioning and you could set up a very positive investment-reward scenario for users.
Austin Govella
483 Reputation points
Posted 2006/09/21 @ 04:51AM with
This was cool, and I definitely think it needs more exploration. Specifically, guidelines (and anti-guidelines) so designers can more easily make their signifiers more ambient.
Tufte might offer some additional examples as well. His recommendation is to always use the least possible difference.
I can’t remember which book, but in one (or several) of his books, he has some nice samples where he’s redesigned really aggressive pieces and communicated more effectively by removing entire design elements, muting colors, and lessening the presence of of other elements (like type, lines).
Michael Beavers
69 Reputation points
Posted 2006/09/22 @ 13:57PM with
Amazing ideas here. My company always uses custom-scored music and frequently employs ambient background noise to evoke emotional response to an immersive, rich media environment. However, I don’t believe we’ve ever attempted to use sound and scoring as a navigational aid.
I also wonder if there aren’t significant implications for bringing a mixture of emotionally evocative qualities and usability through sound for disabled Web users. A sight-impared user, for example, is essentially what a Tokyo subway rider is if they never look up from their novel.
I appreciate your article…definitely thought-provoking.
Tyler Tate
4 Reputation points
Posted 2006/09/23 @ 08:23AM with
I think this is a very important concept. However, if every website tried to accomplish this in a different way, the internet could become quite confusing with hundreds of ambient cues overwhelming users. The beauty about the Tokyo Rail System is that the same principles are carried out universally. For the web, I think consistent ambient cues from one site to another are very important for the success of this idea.
Adam Greenfield
26 Reputation points
Posted 2006/09/26 @ 09:31AM with
In the HCI community, the sort of ambient audio signals you’re discussing here are generally called “earcons.”
I would not make the mistake of collapsing ambient signals with those that occur at low frequency. Indeed, it may be difficult to learn a “language” of cues invoked at infrequent intervals, and many of the most successful ambient signalling channels are those that are engaged constantly or nearly-so.
Jonathan Baker-Bates
16 Reputation points
Posted 2006/09/27 @ 04:54AM with
Just to pick up on a minor point at the risk of coming across like a neo-Marxist nutjob…
The following comment in the article may seem at first innocuous: “An online publication could feature this month’s articles in high-contrast colors, while previous months are rendered more subtly.” However, I have a big problem with news sites, editorial control, and the idea that what goes for offline news should apply to the online variety. The problem I have can be summed up by the question “Why do I need to be told what is important news, by somebody I do not know, who knows nothing about me?”
This isn’t so much a UX issue I know, but I find it immoral that somebody should edit online news, let alone design a system that ingrains this editorial action. Offline news I have to accept is constrained by physical space, so I can tolerate that – but not on line. Sub-editing, yes, authoritative comment, fine, but deciding what I need to see, or what is important – no.
Nice article though, since this is an area that needs more attention in the overall design process. BTW the BBC’s “patina” idea was retired a couple of years back for being far too subtle, and in my opinion, pointless.
Ross Howard
84 Reputation points
Posted 2006/09/27 @ 14:25PM with
I would like to thank everyone who read this article, and also the people who have taken time to write comments and feedback.
I’d like to re-iterate that this article is not about using sounds on the web (not that I am always opposed to that idea). It merely uses the Tokyo rail network’s adoption of melodies as an example of ambient signifiers.
I agree that ambient signifiers may become even more effective if they form and adopt conventions. I suspect these patterns will emerge through further research and maturation.
My use of the word ‘frequency’ was a little too ambiguous. Ambient signifiers tend to be constant throughout the session – essentially occurring only once per signifier (but persisting). High frequency elements such as icons and textual data tend to be physically smaller and independently repeated (with a high occurrence/recurrence).
My examples are merely there to demonstrate possible uses for ambient signifiers. They are not intended to define appropriate adoption or utilisation. One could debate the morality of editorially controlled content, but this is another topic in itself – albeit an interesting one.
I was aware that the BBC’s “patina” was no longer in use. I would be interested to see any research and user testing that was done into its original goal and subsequent results. Personally I think that whilst it may not have been a particularly successful implementation (who knows?) this does not preclude the use of ambient signifiers in general. But clearly more research and evaluation needs to occur.
tomek tomek
0 Reputation points
Posted 2006/09/29 @ 06:52AM with
can’t remember which book, but in one (or several) of his books, he has some nice samples where he’s redesigned really aggressive pieces and communicated more effectively by removing entire design elements, muting colors, and lessening the presence of of other elements (like type, lines).
Daniel Schmidt
0 Reputation points
Posted 2006/09/29 @ 10:42AM with
I think a cleverly designed subway system has a deep impact on society. In a sense, it teaches the public to think logically. If a subway system is confused or disorienting, it can make the whole world feel disorganized. It would be interesting to examine how people apply the patterns of their subway system throughout their lives.
Adam Greenfield
26 Reputation points
Posted 2006/09/30 @ 15:06PM with
Ross, I’m glad to see your clarification. I’d like to propose that for consistency’s sake we take the next step here, and define ambient interface elements as those that remain peripheral and are not ordinarily focally attended to by the user. (This would both bring our discussion into line with standard usage and allow us to eliminate any consideration of “frequency.”)
That said, I feel that the use of ambient audio-channel indicators remains an interesting and underutilized strategy in interaction design. The MIT Media Lab Tangible Media group’s 1999 ambientROOM is a crucial early elaboration of the idea; I suppose the whirring of Natalie Jeremijenko’s “Live Wire” (also known as “Dangling String”) could be considered a still-earlier example. While innovators like Schulze & Webb continue to explore the possibilities of ambient display in the visual channel, relatively few recent projects have fully exploited the possibilities of ambient sound.
Jason Ford
11 Reputation points
Posted 2006/09/30 @ 19:47PM with
Great article.
To me, the best thing about ambient signifiers is that user’s don’t have to consciously recognize them to accomplish tasks on the site. In other words, since they stay secondary, users who don’t notice the signifiers (consciously or subconsciously) will still be able to go about their business. This independence from functional navigation and wayfinding should be a key qualifier for determining if something is an ambient signifier.
When implemented well, this type of system should not introduce confusion since most users won’t even be aware of it – with the net effect ranging from zero impact to a very positive impact on user experience.
Jonathan Baker-Bates
16 Reputation points
Posted 2006/10/05 @ 10:41AM with
I quite accept that your examples are merely there to demonstrate possible uses, but I worry when I read articles like this that posit a good thing (like ambient signifiers) that don’t then then follow through with solid examples. To take an extreme position: if the Tokyo underground usage is the only good example, then that’s an indication that perhaps the idea is not actually valid. The BBC’s “patina” experiment does little to show whether ambient signifiers on the web are appropriate or indeed even useful. My own opinion is that a web patina is not a good idea, since it would by definition discourage users from looking at content that they may well be interested in (for example, a temporary attractor hook). The fact that it would, over time, increasingly limit their ability to notice other things on the page makes it even worse in my opinion.
However, please don’t see this as strong criticism. I am very grateful to you in writing this article beause it’s given me pause for me to think about this.
Constantinos Michael
2 Reputation points
Posted 2006/10/07 @ 11:43AM with
After reading your article, I’ve tried very hard to find examples in non-web applications that employ these techniques. Off the top of my head, Firefox is a great example – not only the yellow address bar to signify security, but also the red search box in the bottom when your search item is not found on the page. MacOS X, when searching in the preference pane, desaturates and darkens the window, except for the icons relevant to your query; the icons that have partial matches appear colored with penumbral shadows, and the full matches appear with umbras. But perhaps the best example I’ve seen comes with certain Unix shell customizations that change the user prompt to a different colour if you’re logged in locally or remotely, and darken and lighten the prompt according to the laod of the machine.
I mention this because I think there’s great room for improvement in these areas. Perhaps the MacOS X dock should also change its hue slightly to reflect the machine load. Connectivity to the internet could be indicated by making the shadow of every window that has accessed a remote IP slightly red (Imagine what a great security feature this would be!) How about physical mediums? Library overdue notices should be printed on paper ranging from light pink to red (I receive multiple for the same book, but naturally, I ignore the first few) – similarly, package notices (from USPS, UPS, and Fedex) could use a similar system. Subway systems could use the improvements the Tokyo line has, and more: in New York, the signage leading to the north exit should be a different color than the south.
Much can be done with pigment altering chemistry: Thirty-day Metrocards should be printed on special paper than gets increasingly redder as its expiration aproaches. I’ve seen something similar done in some parking spaces, where either by accident or thoughtfulness, the machine dispensed ticket you stick to your window fades out completely in 24 hours, allowing an inspector to immediately spot a violation. Cups could show the temperature of their contents.
Steve Portigal
2 Reputation points
Posted 2006/10/17 @ 18:11PM with
It’s great to see this issue come up again, with such a thoughtful approach (and great discussion). In grad school many moons ago I was part of that auditory interface scene (if there was ever a scene) Adam refers to. Some called it “earcons” while others felt that term wasn’t broad enough and on and on it went.
For my thesis I tried and semi-failed to create a tone language for navigating hypertext structure. This was pre-WWW, and was based on some naive assumptions about how people could or could not learn to move around virtual space. The research was really rudimentary but there were some intruiging things that people COULD learn to do. You can see a PDF of a paper I haven’t looked at for a long time at http://www.icad.org/websiteV2.0/Conferences/ICAD94/papers…
Sheila O. Denn
0 Reputation points
Posted 2006/10/20 @ 10:26AM with
This is a really interesting thread—I too would like to see more work done on ambient signifiers. One thing to occurred to me in reading some of the responses is that how ambient signifiers could be used on the Web probably depends at least to some extent on how the particular Web site in question is being used. I wonder if ambient signifiers wouldn’t be more useful on internal organizational websites—where members of the organization are likely to be regular users and may have more of an opportunity to train themselves in responding to ambient cues.
Claudio Vandi
3 Reputation points
Posted 2006/10/24 @ 03:25AM with
It seems to me that an important issue related to ambient signifiers would be: how to use perceptive cues to create a coherent ground?
I mean: what looks great to me when I use Mac OSX is that the window’s shadow and elements (keys, buttons and colours) are the same for a folder window, an application window and a browser window. On one side we have the nonsense of calling all these components with the same name (windows), which should (and does) confuse the user. On the other hand we have some “ambient signifiers” based on salient perceptual figures that create relations between different areas of the screen. That’s not just estethic, it’s pragmatic: figures are used to act in unknown contexts. To use your example, in a Tokyo train a user who have lost the cognition of which line he is using at the moment, can be helped by a sound at the next station. In the same way, the user who doesn’t understand how to delete a file from a new application he’s using will be helped by a “recycle bin like” icon or he’ll try to use a combination of keys he is used to. I developed these ideas in my thesis on the semiotic of GUI (if you want to know something more read my suggestion: 3722) and I’m glad to see a similar direction in what you wrote.