Image caption Campaigners say advertising is exploiting public spaces which many people would like to be free from commercial influence

Jordan Seiler loathes outdoor advertising.

"If you live in a city, your right to the public space and how it is used is an innate feature of your habitation of that environment," says Mr Seiler, an activist with the PublicAdCampaign.

Many agree, he says.

"I find an exasperated public who would like to see less or no advertising at all," he says.

"And then there is a group of entrepreneurs, real estate owners and advertising business owners who enjoy the current system of exploitation of public space."

Protective public

Public space differs from personal space, which most narrowly defined can be seen as "the emotionally-tinged zone around the human body that people feel is 'their space'," according to University of California Prof Bob Sommer.

Image caption Efforts to prevent companies from invading people's personal space are often futile

Public space, by contrast, consists of shared, open areas such as streets or parks or, arguably, shops or restaurants.

A growing number of people are trying to protect both.

People try to shield their private space, in the broadest sense, with tools such as Baby on Board badges in cars, Keep Out signs on their garden gates or No Junk Mail signs on their front doors.

Preventing electronic intrusion or nuisance calls is more complicated, so people tend to resort to companies for help.

Junk mail filters are offered by software providers, while millions of people use telecoms services to block unsolicited sales or marketing calls.

Control and charge

Image caption Free space is invariably part of a broader package aimed at attracting customers

The public's disquiet does not deter companies from trying to make money from controlling space, however.

Take London's hotel sector, where those with the most money are offered the most space, ranging from £11 a night in a 22-sq-m, 14-bed, mixed-sex dorm, to £14,000 for a night in The Lanesborough's 380-sq-m signature suite.

Free space, such as bars, is invariably part of a broader package aimed at attracting particular customers.

Legoland Hotel in Windsor, for instance, has an open bar area for the adults, overlooking the central stage and children's play area.

Ears, nose and eyes

But companies are not content with charging for space, or with pushing unwanted leaflets through your door or calling you while you are in the bath.

Image caption Visual advertising in public spaces is increasingly joined by sounds and smells that companies think will help them attract more customers

In public spaces all over the world, companies are gunning for consumers' attention, intruding through their ears, nose and eyes, constantly assaulting them with sounds, smells and visual props.

All the senses can be manipulated to attempt to alter consumer mood, and in turn purchasing interest and perception of the quality of a product.

Some 83% of marketing budgets are focused on the eyes, according to Martin Lindstrom's book Brand Sense.

Stimulate two senses and the brand impact increases by 30%, rising to 70% when a third is added.

Utilised senses

The way companies use smell and sound in addition to visual tools such as advertising posters is not obvious.

The sense of smell, "has a direct connection to the emotional brain, unlike the other senses", according to Andreas Keller, research associate at The Rockefeller University.

Image caption In addition to looking attractive, cafes appeal to customers attracted by the smell of coffee

"Evolutionarily, the emotions elicited by smells are disgust and fear - and whatever the opposites of these emotions are - and social or sexual emotions.

"Associated with these behaviours are very basic value judgements - 'safe to touch', 'good to eat', 'safe to be around', 'good to have sex with'."

Wake up and...

Companies know this well.

US company Inscentivation, for example, owns a scent that increases betting on slot machines in casinos by 45%, while UK company Bodywise treats its bills with an odour that makes them 17% more likely to be paid, according to Aroma, a book by Constance Classen, David Howes and Anthony Synnott.

Mr Keller says it is likely that other companies do similar things, though he has "no evidence that Apple, Starbucks, Abercrombie & Fitch, or casinos are using smells - other than that I can smell it".

"Apple is not going to tell you what odour they use and how it affects their bottom line, because then you could just spray any computer with their smell and turn it into an Apple computer."

The sounds of ringing tills

The use of canned music follows a similar theme.

Image caption Does slow music make people spend more, or do customers grow immune to canned Mozart?

"If you play slow music in supermarkets, people tend to browse more slowly and look at more products. As a result, they spend an average of 10-20% more," according to Curtin University Professor Adrian North.

Beyond retail, LA Fitness in Moorgate pipes Latin American music to inspire people to take their Zumba classes.

London Underground prefers the classical vibe, following a trial started seven years ago at Elm Park. It now plays calming classical music at more than 65 stations across the network.

Does it work?

But the marketeers cannot win them all.

Fed up with "the impossibility of finding places to eat, drink, or shop without being assaulted by unwelcome, inescapable and unasked-for music", Nigel Rodgers and a few like-minded people founded campaigning group Pipedown in 1994.

"I doubt if piped music really works in the longer term," he says.

"It's like scarecrows that need changing frequently as crows get used to them. Youths will grow used to canned Mozart."