This investigation was designed to determine the influence of metaphorical priming on students' comprehension of issues and concepts pertaining to the U.S. Constitution when students studied the subject matter in a problem-based hypermedia instructional system. Sixty-five high school seniors studied the system for 5 days after receiving relevant, irrelevant, or no metaphorical priming each day. Results revealed deep level comprehension and personal understanding of the instructional system only for students receiving the relevant metaphorical primer. Surface level retention as measured by multiple choice questions failed to vary between groups. Discussion focuses on theory and the use of metaphorical primers to incur deep level processing in hypermedia-based instruction. (Contains 2 tables and 4 figures.)