Bhopal: People take part in ‘Rangpanchami Ger’ celebrations, in Bhopal, Saturday, March 30, 2024.
| Photo Credit: PTI

Questions:

1. In a person with X, stimulating one sensory pathway, like smelling petrol, evokes a response from a different pathway, like seeing a blue square. For example, people with chromesthesia, a form of X, see colours when they hear sounds. Name X.

2. Y is an unusual feature where a person might see colours in an image that aren’t really there, i.e. a disagreement between perception and sensation. It happens when the viewer doesn’t know where the source of light in an image is. Name Y.

3. The Kruithof curve shows colours on a graph that are pleasing to the eye. The graph is a plot between ___________ on one axis and colour temperature on the other. Colours towards the plot’s centre are said to resemble those from natural sources. Fill in the blank.

4. Physical objects don’t have Z but they’re known to exist in a theoretical sense thanks to the mathematics used to describe all colours. One theory to explain the ‘invisibility’ of Z is called the opponent process. What is Z referring to?

5. Sometimes when you expose your eyes to a particular image for more than a short duration, then take it away, your eyes continue to see the image. When this happens in the form of a disorder, it’s called palinopsia. When it happens due to natural conditions, what is it called?

Visual:

A common test to check for colour vision deficiency, colloquially called colour blindness, is called the ________ test. Fill in the blank with the name of the person (shown) who invented it.

Answers:

1. Synaesthesia

2. Colour constancy

3. Illuminance

4. Impossible colours

5. Afterimage

Visual: Ishihara