Advances in recent technology have changed the evidentiary sources presented in both criminal and civil trials to include the use of full-motion, computer-generated animations. The presentation of computer-generated animations can increase juror retention, understanding, and synthesis of information, or it can act as a persuasive tool to undermine the deliberative process and to unduly influence juror decision making. In the advent of such new technology use, a balance must form between the usefulness of such evidentiary tactics and the elimination of undue influence or abuse of new technology. General foundational principles of demonstrative evidence apply to authenticate and determine the relevance of admission of such evidence. The Federal Rules of Evidence are not properly equipped to handle the implications of such new evidence and have provided little to no guidance for judges to determine admissibility. This Note discusses the analysis of the impact of computer-generated animations from the perspective of psychology. Through the application of psychological principles, this Note presents suggested guidelines for judicial determination of admissibility or inadmissibility of computer-generated animations as unduly prejudicial. Finally, this Note proposes an amendment to Federal Rule of Evidence 403 and the accompanying Advisory Committee’s Note to accommodate the advanced technology.