Anything that prevents understanding a message is a barrier to communication. The barrier is like a filter which may filter out the originality or true meaning of an idea or a message. Our culture, background, bias allow us to use past experience to understand something new, it's when they change or distort the meaning of the message then interfere with the communication process.
Before getting ready for an effective communication, we need to throw out the "Me Generation", which are defensiveness (we feel someone is attacking us), superiority (we feel we know better), and ego (we feel we are the center of activity).
If we feel there are such barriers as a person who talks too fast, who is not articulately clearly, we may dismiss the person.
Sometimes our preconceived attitudes affect our ability to listen. We tend to listen uncritically to persons of high status and dismiss those of low status.
Semantic distractions occur when a word is used differently than you prefer. For example, if someone uses the word "chairman" instead of "chairperson" some people may focus on the word and not the message.
People don't see things the same way when under stress. What we see and believe at a given moment is influenced by our psychological frames of references---our beliefs, values, knowledge, experiences, and goals.
Environmental factors such as lighting, noise, color or people around may also distract us from effective communication.
Sometimes we assume some information has no values to others or others are already aware of the facts, so we stop ourselves from sharing information, which results in ineffective communication as well.
