In Kelley Armstrong's book "The Calling," a character expresses frustration that resonates with many people who experience mental strain. The character mentions rubbing their temples, a common gesture associated with trying to alleviate discomfort or stress. This action leads to a remark from another character suggesting that the pain isn't necessarily a headache, but rather a result of mental exhaustion and the challenges of deep thinking. This exchange highlights the complexities of mental effort and the toll it can take on a person, emphasizing that the struggle is often not just physical but deeply emotional and cognitive as well. It serves as a reminder that sometimes our mental anguish manifests in physical ways, illustrating the intricate connection between thought, emotion, and physical well-being.