The phrase "doth top of your head" can also be expressed as "off the top of your head," which means to say something quickly and without thinking about it too much. Other synonyms for this phrase include "spur of the moment," "impromptu," and "on a whim." These phrases all imply that the speaker is acting without much forethought or planning, and may be relying on instinct or intuition to guide their words or actions. Alternatively, more deliberate synonyms might include "calculated," "deliberate," or "thought-out." Whatever the situation may be, it's important to choose the right words to accurately reflect your intentions and communicate effectively.