Self-concept, or self-identity, refers to the ideas one holds regarding himself or herself. These ideas refer to one's sexual preferences, academic mind, cultural/racial identity, personality, and physical characteristics. Communication with others greatly depends upon how one compares himself or herself to others, the environment, personal anxieties, and the people around.
For example, a person who is homosexual may communicate very well (openly) with other homosexuals. On the other hand, if the same person is around people he or she considers to be homophobic, the conversation can be strained. The person may try to hide who he or she really is based upon internal shame felt.
Another example of a situation, where a conversation may be strained or easy-going, could be one where a person feels uncomfortable regarding the cultural or racial environment. For example, an African American man may feel uncomfortable around a group of southern whites. The conversation would be guarded (most likely). On the other hand, if the African American was around a group of other African Americans, he would feel the same (as the previous example) and conversation would be more easy-going.
In some cases, people who feel below others (in any way) may not choose to converse in a group setting. Instead, he or she may choose to stay quiet (feeling self-conscious about what he or she could add). The person may feel as if he or she were to say something that he or she would be judged (given the lack of "equality").
Other people have very strong self-concepts. These people will have a conversation with anyone at anytime. Nothing makes them feel out of place, and they thrive in social settings.