From the 1200s through the 1600s, parts of Europe were afflicted with deadly, mysterious outbreaks of seemingly contagious, unstoppable dancing. While it's still unclear exactly why these "dancing plagues" happened, modern psychology may...

Ever zoned out while driving or felt like you were watching your life from outside your body? You're not alone. This video explains dissociation, a common but often misunderstood experience.

Dissociative identity disorder develops when person fails to form a total personality that integrates all aspects of yourself and your emotions. For more on dissociative states watch this video on depersonalization. What Is...