Since achromatic vision was the first to evolve it explains why the majority of the population are not affected by black-white color blindness.

Scientific Paper: "Retinal mechanisms for chromatic and achromatic vision"

Achromatic vision:

Ladd-Franklin noted that: "some animals are color blind and assumed that achromatic vision appeared first in evolution and color vision came later.

Ladd-Franklin concluded that color vision evolved in three stages: achromatic vision (black and white), blue-yellow sensitivity and red-green sensitivity.

Achromatopsia is strictly defined as the inability to see color.

If a person has complete achromatopsia, then their entire visual field is devoid of color.

Complete color blindness, or achromatopsia, is very rare but more severe.

This most severe form is known as achromatopsia.

Cone function and day vision have been restored for at least 33 months in two young dogs with achromatopsia.

Variants in this gene have been shown to cause achromatopsia and color blindness.

In patients with achromatopsia, the cone system and fibres carrying colour information remain intact.

For example, people with achromatopsia suffer from a completely different disorder, but are nevertheless unable to see colors.

People lacking the three types of photopigments are said to have complete color blindness or achromatopsia.

This can occur in people who had achromatopsia, but the brain recovered from the injury, restoring some color vision.

There is generally no treatment to cure achromatopsia.

Cerebral achromatopsia differs from other forms of color blindness in subtle but important ways.

Four generations after this population bottleneck the prevalence of achromatopsia is 5% with a further 30% as carriers.

Especially pertinent is the analysis of how cerebral achromatopsia affects his practice as a painter and artist.

Like akinetopsia, perception of color can also be selectively disturbed as in achromatopsia.

In cerebral achromatopsia, a person cannot perceive colors even though the eyes are capable of distinguishing them.

This was further supported from lesion studies where individuals were unable to see colours after damage, a disorder known as achromatopsia.

Descriptions of cerebral achromatopsia's effects on his psychological health and visual perception are especially striking.

Scdoris was born with congenital achromatopsia, an uncorrectable visual disorder.

Cerebral achromatopsia is a chronic condition where a person is unable to see color, but they are still able to recognize shape and form.

The people of this region have termed achromatopsia "maskun", which literally means "not see" in Pingelapese.

Affected individuals commonly suffer from photophobia, nystagmus and achromatopsia.

However, the achromatopsia disorder did not appear until the fourth generation after the typhoon, where 2.70% of the Pingelapese were affected.

A person with dyschromatopsia, or incomplete achromtopsia, has similar symptoms to complete achromatopsia, but to a lesser degree.

Such loss of function will undoubtedly negate the cone cell's ability to respond to visual input and produce achromatopsia.