A cyclist and his canine companion on the Walmer Street bridge in Abbotsford. But his colour choice – floor-to-ceiling black to match his black road bike – is unlikely to garner credits from road safety organisations. VicRoads advises cyclists to "wear a bright top day and night" and in 2014 mandated learner motorcyclists wear an approved high-visibility vest or jacket. In 2013 New Zealand coroner Ian Smith went further, saying high-visibility clothing for cyclists was a "no-brainer" and should be compulsory. Meanwhile, the City of Melbourne Bicycle Plan, released in March, puts a target of zero fatalities and serious injury crashes by 2020 front and centre.

A cyclist behaving badly on Royal Parade in Melbourne's north. Credit:Jason South "I actually did buy a bright yellow fluoro jersey and every time I put it on I felt like I lit up. It just didn't feel right," says Spurling. So, does Spurling's sombre cycling chic put him at risk of ending up, literally, a fashion tragic? Rain and damaging winds are expected to hit the city about 6.30pm. Credit:Pat Scala Garry Brennan, senior policy advisor at Bicycle Network, is not so sure.

"Crash evidence often indicates the cyclist was not observed by the driver and the conclusion is that the cyclist was difficult to see. We challenge that conclusion and that it can be solved by dressing the cyclist up in bright clothing," says Brennan. Trading parking and speed for safety, a cyclist rides on Sydney Road, Coburg. Credit:Jason South It seems baffling that a peak cycling advocacy body could question the value of high-vis clothing, but evidence is gathering behind it. Dr Sandar Tin Tin, research fellow in the faculty of medical and health sciences at the University of Auckland, recently finished a six-year PhD study of cyclist visibility. Braving the traffic in Lonsdale Street in Melbourne's CBD. Credit:Eddie Jim

"Being visible is different from being noticed. Visibility is about standing out from the background and cyclists can enhance that, especially in poor weather or low lighting conditions, by wearing high-visibility materials," says Tin Tin. "But being noticed is different because it depends on drivers' attention to and expectation of the cyclists," she says. This distinction is key to a Transport for London commercial, viewed more than 22 million times on YouTube, that asks viewers to count how many passes a basketball team makes. SPOILER ALERT

Number nerds will be gratified to learn the answer is 13 but they're missing the point, which is actually the bear that moonwalks through the game mid-action. Yes, the bear. Half of the viewers don't spot the bear. "It's easy to miss something you're not looking for. Look out for cyclists," exhorts the ad, which draws heavily on a 1999 experiment by psychologists Daniel Simons and Christopher Chabris that features an "invisible" chest-thumping gorilla. The gorilla has become something of a fixture in the literature on so-called "inattentional blindness" and has even duped experts. In 2013 researchers at the Harvard Visual Attention Lab craftily inserted a three centimetre by five centimetre gorilla image into a CT scan and asked radiologists to examine the scan for lung nodules.

Awkwardly, 83 per cent of the doctors didn't notice the gorilla even though eye-tracking software proved more than half of them were looking straight at it. The gorilla image is in the top right of the CT scan. Eye-tracking software (right) indicated that more than half the doctors looked directly at it. What is going on? Dr Steven Most, senior lecturer and ARC future fellow at the UNSW School of Psychology, has impeccable credentials when it comes to ersatz primates. Most did his PhD under Simons at Harvard, was a basketballer in the original experiment and actually procured the gorilla suit.

"Attention and expectations seem to play a more profound role in shaping what we become aware of than the salience of a stimulus," says Most. In one experiment Most had people follow black or white shapes that bounced around a computer display until, mid-experiment, a red cross makes an appearance and coolly crosses the screen. "It's the only red thing in the display, it's like the visual equivalent of an alarm bell. And yet a third of people didn't see it," says Most. If you're focused on black or white squares and circles an unscripted red cross can effectively become invisible. On the road, sheer weight of numbers means drivers expect to see cars and trucks and so their attention dutifully shifts towards them. Solitary bicycles, blazing fluoro or no, are like Most's red cross; they simply can't count on being noticed.

Tin Tin's findings tally eerily well with the psychology. She graded the visibility of riders in New Zealand's Lake Taupo Cycle Challenge based on the use of fluoro, lights, reflective materials and the main colour of their jersey, helmet and bike frame. Over a several-year follow-up 162 riders had crashes with vehicles, but their reported visibility didn't predict the risk of a collision. "We concluded that visibility aids are not very effective in the New Zealand transport environment," says Tin Tin. What did seem to matter was the proportion of bikes to cars in the traffic mix.

"We analysed cycling risk across New Zealand. Auckland had the highest level of car use and the lowest level of cycling. It also had the highest risk of cycling injuries," says Tin Tin. The finding supports the idea that for cyclists there is "risk in scarcity"; as bicycle numbers dwindle motorists are less likely to expect them, less likely to notice them, and more likely to collide with them. That seems to hold even for riders in dazzling fluoro (or, for that matter, sporting a gorilla suit emblazoned with a red cross). And the fact that motorists' attention is a finite resource just adds volatility to the mix. An Irish study published in May had people in a life-size Volkswagen Polo driving simulator negotiate a road with cars parked on either side.

When the gap between the parked cars was easily wide enough to get through 22 of the 41 drivers noticed an unexpected pedestrian in a red blouse. But when drivers had to contend with a gap barely wide enough for the VW only seven noticed the pedestrian. The study fuels concern that increasingly complex and cluttered roads tax the attention of drivers and put unexpected cyclists at even greater risk. A popular policy response is simply to tell drivers to look out for cyclists Last year the Amy Gillett Foundation and the NSW government launched the It's a two way street campaign that tells motorists, "Just as you expect to see other vehicles on the road, expect to see people riding bikes too".

But Chabris and Simons are downbeat on this kind of public service entreaty in their bestselling book The Invisible Gorilla. They concede drivers who see a sign "look for motorcycles" might be more likely to notice motorcycles for a short time. But after a few minutes of not seeing any motorcycles the drivers' "visual expectations will reset, leading them to again expect what they see most commonly – cars", they write. Brennan's favoured solution seems to follow logically; he wants to combat risk in scarcity with safety in numbers. "In Copenhagen on a morning commute you wouldn't see one in a thousand bikes in high-vis ... in Copenhagen bikes are completely normalised, people expect to see them," says Brennan.

In Copenhagen 41 per cent of people cycle to work or school yet, at 1.5 deaths per 100 million kilometres, Denmark's cycling fatality rate is well below that of countries where fewer people ride, such as the UK and US. And a May report by the Norwegian Centre for Transport Research found that as cyclists flock to Oslo streets in spring their risk of collision drops because drivers expect to see them, also supporting safety in numbers. Melbourne's new Bicycle Plan pledges to get more people cycling through "safe infrastructure" and, "improved facilities and route connectivity", but the white charger of technology could well get here first. The June report from Google's self-driving car project showcased night footage of the vehicle – which has 360 degree "vision" – confronted with a pedestrian and an oncoming bicycle when, suddenly, a miscreant cyclist veers across its path. The autonomous vehicle deftly misses all three (and later dodges a wheelchair-bound woman chasing a duck with a broom, several frog-hopping pedestrians, and a semi-naked man).

Indeed, Volvo has offered an optional cyclist detection system with full auto brake since 2013. Such technology may well be a boon for Spurling who remains unmoved by brights even as they gain a toehold in the cycling fashion catalogue: "It's more a mindset for me. I've just always worn black". Twitter @pbiegler