Final answer:
Hearing the sounds of an orchestra and experiencing this as seeing colors or smelling aromas is known as synesthesia, a condition where stimulation of one sense involuntarily triggers experiences in another.
Step-by-step explanation:
If hearing the sounds of an orchestra caused you to see blue and green colors or smell sweet aromas, you would be experiencing synesthesia. Synesthesia is a neurological condition where stimulation of one sensory or cognitive pathway leads to automatic, involuntary experiences in a second sensory or cognitive pathway.
People with synesthesia might taste shapes, feel sounds, or as in your example, see music as vivid colors or associate it with distinct smells. This can happen because, in synesthesia, there are cross-connections between areas of the brain that are normally not linked.
The phenomenon of synesthesia may be related to how we perceive colors and sounds. There are theories such as the trichromatic theory and the opponent-process theory that explain how we perceive color, but synesthesia transcends these typical processing routes, intertwining different senses.
For example, certain sounds or music can evoke the perception of colors that are not actually present, which is seen in the case of the orchestra causing one to see colors. These sensory experiences can vary significantly among individuals with synesthesia.