It's All in Your Head' is a phrase that is often used to describe the IDEA that one's thoughts and feelings are all within their own control. The crossword solutions for this phrase are DREAM (5 letters), KNOWLEDGE (9 letters), BRAIN (5 letters), EGO (3 letters), IDEA (4 letters), and CEREBRUM (8 letters). DREAM is a state of consciousness in which one experiences images, sounds, and other sensations while sleeping. KNOWLEDGE is the understanding of facts, truths, or information acquired through experience or education. BRAIN is an organ located in the head that is responsible for controlling the body's functions. EGO is the sense of self-importance or self-esteem. IDEA is a thought or concept that can be expressed in words or pictures. Cerebrum is the largest part of the BRAIN and is responsible for higher mental functions such as thinking, reasoning, and problem solving.