Colour vision

Which term denotes normal colour vision?

Trichromacy

What are the three types of cone cells?

Red, green, and blue

What wavelength and colour do S-cones respond to?

Blue light, 400-480nm

What wavelength and colour do M-cones respond to?

Green light, 460-510nm

What wavelength and colour do L-cones respond to?

Red light, 510-700nm

True or false? - Colour perception can be achieved by individual cone cells responding alone to stimulation by a particular wavelength and intensity of light.

False - colour perception relies on the comparison of numerous cone cells, because similar signals are generated by one cone in response to many different combinations of wavelength and intensity. This is known as univariance.

What is achromatopic vision?

Complete absence of any functioning cone cells, leading to perception of shades of grey only.

What condition can congenital achromatopsia be commonly associated with?

Infantile nystagmus

What are the three classifications of dichromatic vision?

Protanopes, deuteranopes, tritanopes

Match the type of dichromacy with the type of missing cone:

Protanope - missing L-cones; deuteranope - missing M-cones; tritanope - missing S-cones.

What are the types of heritable red-green colour blindness?

Protanomaly, protanopia, deuteranomaly, deuteranopia

What are the types of heritable blue-yellow colour blindness?

Tritanomaly, tritanopia

What are the three types of acquired colour deficiency?

Type 1 - cone/RPE dystrophies; Type 2 - optic neuritis; Type 3 - AMD, glaucoma, rod dystrophies

What are the two main types of colour vision assessment?

Colour discrimination and colour arrangement

What are the clinical options for colour vision testing using isochromatic plates?

Ishihara and Hardy Rand Rittler

Which of HRR and Ishihara can be used to assess optic neuropathy?

HRR has been proven to be more effective at detecting optic neuropathy, as it can detect both protan-/deuteranomalies and tritanomalies.

What are the types of colour arrangement tests?

Munsell-100 and Farnsworth D-15