Last autumn, the American Automobile Association complained that Hollywood wasn't setting a good enough example as far as the wearing of seat belts was concerned. Too many movies advocate the James Bond school of crash survival, it said, while in the real world, seat belts save lives. So it might come as something of a shock to the AAA to learn that habitual seat belt-wearers tend to drive more dangerously than their unbelted counterparts.
That, at least, is the conclusion of Dr Tony Reinhardt-Rutland of the University of Ulster, who presented his findings yesterday at the British Psychological Society's annual conference in Belfast. And the reason, he says, is that seat belts eradicate an effect known as 'looming'.
Looming is what happens to you when, unrestrained by a belt, you slam your foot on the brake to avoid hitting something. You are thrown forward and the world - the dashboard, the windscreen, and the scene beyond it - rushes up to meet you. That visual expansion is frightening and, not surprisingly, acts as an incentive to drive more cautiously.
'Looming is a primitive response and creatures, including man, find it very uncomfortable,' says Dr Reinhardt-Rutland. 'It's something that will have an effect on their behaviour. They will learn from it.' Consequently, in the absence of looming, people tend to drive less cautiously: they don't leave as much space behind the car in front, they overtake in trickier conditions. And that, says Reinhardt-Rutland, is why seat belts save fewer lives than they should.
Wearing a belt in the front seat of a car became compulsory in Britain in 1983. Since then there have been additions to the legislation and, as far as cars are concerned, the law now requires you, as an adult, to wear a belt if one is available, front or back. The early eighties saw a reduction in road accident casualties, with the number of deaths in Britain dropping from 6010 in 1980 to 5165 in 1985 - not bad considering that the volume of traffic increased by 14 per cent over the same period. And in 1985, a triumphant Department of Transport survey concluded that seat belts were indeed effective.
But that survey might have been premature. By 1986, the number of deaths had stopped falling and had begun to level off. According to Dr Reinhardt-Rutland, people had forgotten how scary it is to be loomed at and had adapted their behaviour accordingly. They were driving less carefully and faster. Since seat belts came in, he says, the average speed of cars in built-up areas has increased from about 28mph to 33mph. As a result, cars pose a greater threat to other road users. In 1989, for instance, the number of cyclists killed on the road had, following a dip, risen back to its 1982 level of 294.
That people are driving faster is not in dispute. But an investigation carried out in 1996 by Dr Graham Grayson of the Transport Research Laboratory in Berkshire concluded that there was 'no real evidence of any behavioural change' in response to the introduction of seat belts. And Dr Frank McKenna, an expert on driving behaviour at the University of Reading, says that the problem goes far deeper. At the same time that we were getting used to seat belts, he points out, car design was becoming more sophisticated. In his opinion, bad driving habits have less to do with looming than with the fact that, in a modern car, there's no draught.
It makes sense if you think about it. Human beings are designed to move, at the fastest, at around 20mph. Even at a more modest six, you know you're on the move because your heart rate increases, you feel the air moving across your skin, and your eyes and ears tell you that things are passing you by. Ask a group of people to run and close their eyes at the same time, and very few will comply, because the sense of motion through an unseen environment is too terrifying. And yet a man cruising in his Ford Mondeo at a blistering (in human terms) 70 mph will happily turn his head to converse with a back seat passenger for seconds at a time.
'When you're moving in a car, nothing tells you that you're moving,' says Dr McKenna, 'You're actually stationary. You have a nice comfortable seat, there's hardly any vibration, and we have aerodynamically streamed the car so that you get no wind effect.' Generally speaking, the more expensive the car, the less engine noise there is, and his research indicates that people use engine noise as a cue to guide their choice of speed. In fact, the driver of a modern car must rely entirely on his eyes to tell him how fast he is going, and even then - when you consider how few landmarks there are along the average stretch of motorway - information is scarce.
'We need to face up to the fact that we have systematically taken away these cues to speed,' says Dr McKenna. 'The acceleration characteristics of modern cars are much greater, the top speeds are much greater, and at the same time people are being denied the information that tells them they're involved in movement. It's hardly surprising that we've got a speed problem in this country and virtually every other.' The solution, he says, is to give back to drivers that contact with the environment through which they're moving. In early motor cars, you bumped along with the wind in your hair and you had a pretty good idea of how fast you were going, without glancing at the speedo. And some modern sports cars, with their rigid suspensions, are going the same way. Alternatively, says Dr McKenna, you can maintain the smooth ride and bring the external environment into the car. Some road safety experts have suggested, semi-seriously, that the next generation of cars should be transparent, or at least glass-bottomed. Failing that, some kind of head-up display, as pioneered by the aviation industry, might do the trick. 'One of the most common errors on the road is that we drive too close to the vehicle in front,' he says. But if your following distance was flashed up on a windscreen display, perhaps you would be less likely to tailgate.
Dr McKenna admits that it is hard to single out any one factor as being most influential as far as driver behaviour is concerned. Since 1983, not only has the law on seat belts changed, but so has drink-driving legislation. Cars have become more crashworthy, the volume of traffic of the roads has increased, and people think less of driving from London to Manchester and back in a day. But whether the fact that people are still being killed on the roads is down to subtle changes in our braking behaviour, or to the malign influence of the movies, one thing is certain: when it comes to evolution, the motor car is advancing far faster than we are.
