Caused by whatever happens in the environment (e.g. loud siren, disturbing odour, sunglasses, illegible handwriting, blurred type or fonts that are too small, poor grammar, popup ads, etc.)
The relationships among the communicators (e.g. status relationships among the participants, their friendliness or hostility, the formality or informality and the seriousness or humorousness of the situation, etc.)
One's and others' culture (e.g. the beliefs, values, and ways of behaving that are shared by a group of people and passed down from one generation to the next)
A single message (e.g. a public speech on homelessness) may inform a person (intellectual effect), move him/her to feel differently (emotional effect), and lead to a more generous behaviour when come upon a homeless person (physical effect)