Do colours influence our mood?
When the eye perceives colours, they affect us mentally and physically. Generally, dark colours signal peace and quiet, and light colours activity. The effect of a colour varies between countries. In Germany, jealousy is linked with purple, but in Poland, it is yellow.
The effect of colours can also be physical. Red can make the blood pressure rise, while dark blue keeps it stable. Nerve cells in the eye send signals to the hypothalamus brain centre, which releases hormones that control sweat, sleep, hunger, etc.