The most prevalent symptom of schizotypal personality disorder are the odd or eccentric beliefs and behavior of the individual. Depending on the severity, people with StPD can experience moderate to serious impairment in their day-to-day lives, as these unusual thoughts and consequent behaviors can affect their relationship with the people closest to them.
For people with SPD, they often appear to lack a desire for intimacy, and will avoid close relationships with others. They usually prefer to spend time with themselves rather than socialize or be in a group of people. This behavior does not come from a contempt or anxiety from being around other people; rather, people with SPD are more or less indifferent to social experiences.
People with BPD have very heightened emotional responses to everyday situations. Recall the last bad day you had, maybe you had gotten sick during a busy week, or fought with a best friend, or had a significant other break up with you. The emotions you feel in those moments may be intense enough for you to not pay attention to much else. Now imagine, experiencing this not only during times of crisis, but on a daily basis.
Antisocial personality disorder (ASPD) is one of the hardest personality disorders to treat. Not much is known on ASPD compared to more common mental illnesses. According to Lenzenweger, et al. only 0.6% of the U.S population has been diagnosed with ASPD (2007).
Now, 0.6 % percent may not seem like a large percentage. However, when multiplied with the U.S. population of 318 million people, over 1.9 million people in the U.S. are living with ASPD.