A television advert for the Audi R8 has been banned after the Advertising Standards Authority ruled it linked speed with excitement.
In the advert the car can be heard accelerating while the pupil of what is apparently the driver's eye is seen to dilate and contract.
The authority investigated following a complaint that the film had irresponsibly linked speed and excitement.
Under ASA rules motoring adverts are prevented from referencing a vehicle's speed in the context of excitement, aggression or competitiveness.
Volkswagen, which owns the Audi brand, argued the pupil dilation seen in the film, which it said was a natural scientific phenomenon, was indicative of concentration and focus.
And while it acknowledged it might occur due to excitement, it said it could also be caused by other factors.
But ASA disagreed, saying in its assessment: "We considered that viewers would interpret the changes in pupil size as an emotional response to the movement of the car, as represented by the sounds that were audible during the eye sequence."
A spokesperson for Volkswagen told ITV News the company respected ASA's decision to uphold the complaint.