It is one of the highest selling erotic novels ever published despite being panned by the critics.

But perhaps reviewers of Fifty Shades of Grey have been missing some of the books subtleties simply due to their own biology.

It turns out that, despite what the title suggests, humans are only capable of seeing 30 hues between black and white.

The popular erotic novel Fifty Shades of Grey books were not well received by critics but have been turned into a film starring actress Dakota Johnson, pictured above. The title of the book may have been misleading

A recent scientific paper examining how the human eye might respond to electronic screens used by ebooks makes the claim.

THE EMOTIONAL POWER OF FIFTY SHADES OF GREY A recent study found the Fifty Shades trilogy can have a dramatic effect on the personalities of young women. The researchers said young adult women who read the book are more likely than non-readers to exhibit signs of eating disorders and have a verbally abusive partner. As part of the study, more than 650 women aged 18 to 23 were surveyed about their relationships and sexuality. Those who read the first Fifty Shades novel were 25 per cent more likely to have a partner who yelled or swore at them; 34 per cent more likely to have a partner who demonstrated stalking tendencies; and more than 75 per cent more likely to have used diet aids or fasted for more than 24 hours. Those who read all three books in the series were 65 per cent more likely than nonreaders to binge drink – or drink five or more drinks on a single occasion on six or more days per month – and 63 per cent more likely to have five or more partners during their lifetime. Advertisement

By comparison the human eye is thought to be capable of detecting around 10 million unique colours.

This might explain why we have so much difficulty seeing in white out and foggy conditions.

Writing in the Journal of the Royal Society Interface, Eric Kreit and colleagues at the University of Cincinnati, said: 'The primate (eg human) visual system is distinct from many other organisms.

'Humans possess three cone visual pigments for conveying colour information that is said to allow humans to be able to detect approximately 10 million unique colours, but only distinguish about 30 shades of grey.'

The paper was unearthed by Popular Science.

The human eye has four types of photoreceptors that sit on the retina at the back of the eye and are responsible for detecting light.

There are three types of cone receptors that are responsible for detecting a range of colours and one type rod receptors that deal with black and white.

Rod cells in humans have just one type of light sensitive pigment rather than the three types found in cone cells.

This optical illusion relies on the insensitivity of our eyes to shades of grey. The horizontal grey bar is actually the same shade throughout and you can check this by covering the area surrounding the central bar

While the rod receptors are less precise than the cone receptors, they are far more sensitive to low light levels and tend to be what give us our night vision.

There are an estimated 120 million rods in the back of the human eye compared to just seven million different cones.

However, the human eye can distinguish around 10 million unique colours.

Cats have up to eight times more rod cells, allowing them to detect light at lower levels than humans.

The human eye is only capable of seeing 30 shades of grey according to the latest research by scientists

There are a wide range of estimates for how many shades of grey the human eye can detect - often depending on the lighting conditions and the background against which they are viewed.

However, the human eye struggles to distinguish many of the shades of grey that can be projected by modern computer screens.

One study from 2001 looking at how humans process ultrasound images has suggested our eyes may in fact only be able to distinguish between 8-16 shades of grey.

However, there are other textbooks claims humans can actually distinguish around 450 shades of grey.