The aim of this thesis is to explore whether and to what extent being given AI generated interface prototypes helps in the early design process, especially for people on the lowest end of the visual imagination spectrum. Aphantasia is a condition that affects the vividness of visual imagery, which may influence the creativity and cognition of people who are involved in computer interface design. Generative AI is a technology that can produce novel and diverse outputs, such as graphical user interface (GUI) designs, based on some input or prior knowledge. In this thesis, we conducted an empirical study to compare the quality, accuracy, speed, and user experience of people who create wireframe prototypes with or without access to visual AI generated interface prototypes. We also examined the relationship between the benefits of having access to visual AI generated interface prototypes and the placement on the visual imagination spectrum of the participants. We found no correlation between the placement on the visual imagination spectrum and the quality, accuracy, speed nor the user experience of the participants in this study. We also found that being given AI generated images of interface prototypes during the wireframing stage, does not improve quality, accuracy, speed nor user experience of the participants.