Schizoid personality disorder is an uncommon condition in which people avoid social activities and consistently shy away from interaction with others. They also have a limited range of emotional expression.
If you have schizoid personality disorder, you may be seen as a loner or dismissive of others, and you may lack the desire or skill to form close personal relationships. Because you don't tend to show emotion, you may appear as though you don't care about others or what's going on around you.
The cause of schizoid personality disorder is unknown. Talk therapy, and in some cases medications, can help.