The crossword solution for the term 'Cause of Swelled Heads' is EGO, which stands for an exaggerated sense of self-importance or self-esteem. EGO is a psychological concept that refers to a person's sense of self-worth and identity. It is often used to describe someone who is overly confident or has an inflated sense of their own importance. EGO can be both positive and negative, depending on how it is expressed. In some cases, it can lead to feelings of superiority or entitlement, while in others it can lead to feelings of insecurity or low self-esteem.