• Psychological factors are those that have mental and emotional effects.
• Physiological factors address the physiology or mechanics of human vision.
• Environmental factors address the impact of ambient light on color perception.
• Circumstantial factors, deal with the effects when certain colors are accompanied by other colors.

Psychological Factors

Color can be inspirational, evocative, and emotional. Thoughts, feelings and images come to mind just by seeing familiar colors. To many Americans the simple mention of red, white and blue conjures an image of the flag and often a feeling of patriotism. The color red is associated with fire or warmth and is considered an aggressive color, whereas blue is sedate and associated with water or coolness. Water faucets are often labeled in red for hot and blue for cold. Similarly, pictures are described as being warm if they are defined by reds, yellows and oranges and cool if they are defined by blues, greens and violets. Traffic lights rely on red, yellow and green colors to communicate messages to drivers in order to regulate traffic flow. Because red is an aggressive color, people with red cars are perceived to drive faster than those having other colors. Police tend to stop red cars more often since they are responding to seeing the color red. Pink is traditionally considered a feminine color. Baby colors are pastel pink for a girl and pastel blue for a boy. Pastels are called �soft� colors.

Colors are also used to create associations in language: a person can be "blue" (sad), "green" (inexperienced, envious) or "yellow" (afraid). Yellow is generally experienced as sunny, exciting and uplifting. Green as pastoral, suggestive of nature, symbolic of fertility. Purple as the traditional symbol of royalty.

Finally, most of us have a favorite color or colors, and we tend to be biased towards those colors. Often our favorite colors are linked with memorable childhood experiences.